| # JavaTM Debug Wire Protocol Specification Details

- VirtualMachine Command Set (1)
  - Version (1)
  - ClassesBySignature (2)
  - AllClasses (3)
  - AllThreads (4)
  - TopLevelThreadGroups (5)
  - Dispose (6)
  - IDSizes (7)
  - Suspend (8)
  - Resume (9)
  - Exit (10)
  - CreateString (11)
  - Capabilities (12)
  - ClassPaths (13)
  - DisposeObjects (14)
  - HoldEvents (15)
  - ReleaseEvents (16)
- ReferenceType Command Set (2)
  - Signature (1)
  - ClassLoader (2)
  - Modifiers (3)
  - Fields (4)
  - Methods (5)
  - GetValues (6)
  - SourceFile (7)
  - NestedTypes (8)
  - Status (9)
  - Interfaces (10)
  - ClassObject (11)
- ClassType Command Set (3)
  - Superclass (1)
  - SetValues (2)
  - InvokeMethod (3)
  - NewInstance (4)
- ArrayType Command Set (4)
  - NewInstance (1)
- InterfaceType Command Set (5)
- Method Command Set (6)
  - LineTable (1)
  - VariableTable (2)
  - Bytecodes (3)
- Field Command Set (8)
- ObjectReference Command Set (9)
  - ReferenceType (1)
  - GetValues (2)
  - SetValues (3)
  - MonitorInfo (5)
  - InvokeMethod (6)
  - DisableCollection (7)
  - EnableCollection (8)
  - IsCollected (9)
- StringReference Command Set (10)
  - Value (1)
- ThreadReference Command Set (11)
  - Name (1)
  - Suspend (2)
  - Resume (3)
  - Status (4)
  - ThreadGroup (5)
  - Frames (6)
  - FrameCount (7)
  - OwnedMonitors (8)
  - CurrentContendedMonitor (9)
  - Stop (10)
  - Interrupt (11)
  - SuspendCount (12)
- ThreadGroupReference Command Set (12)
  - Name (1)
  - Parent (2)
  - Children (3)
- ArrayReference Command Set (13)
  - Length (1)
  - GetValues (2)
  - SetValues (3)
- ClassLoaderReference Command Set (14)
  - VisibleClasses (1)
- EventRequest Command Set (15)
  - Set (1)
  - Clear (2)
  - ClearAllBreakpoints (3)
- StackFrame Command Set (16)
  - GetValues (1)
  - SetValues (2)
  - ThisObject (3)
- ClassObjectReference Command Set (17)
  - ReflectedType (1)
- Event Command Set (64)
  - Composite (100)
- Error Constants
- EventKind Constants
- ThreadStatus Constants
- SuspendStatus Constants
- ClassStatus Constants
- TypeTag Constants
- Tag Constants
- StepDepth Constants
- StepSize Constants
- SuspendPolicy Constants
- InvokeOptions Constants

  #### VirtualMachine Command Set (1)

  ##### Version Command (1)

  Returns the JDWP version implemented by the target VM. The version string format is implementation dependent.
  Out Data
    (None)
  Reply Data

    string | description | Text information on the VM version
    int | jdwpMajor | Major JDWP Version number
    int | jdwpMinor | Minor JDWP Version number
    string | vmVersion | Target VM JRE version, as in the java.version property
    string | vmName | Target VM name, as in the java.vm.name property

  ##### ClassesBySignature Command (2)

  Returns reference types for all the classes loaded by the target VM which match the given signature. Multple reference types will be returned if two or more class loaders have loaded a class of the same name. The search is confined to loaded classes only; no attempt is made to load a class of the given signature.
  Out Data

    string | signature | JNI signature of the class to find (for example, "Ljava/lang/String;").

  Reply Data

    int | classes | Number of reference types that follow.
    Repeated classes times:
    | byte | refTypeTag | Kind of following reference type.
    | referenceTypeID | typeID | Matching loaded reference type
    | int | status | The current class status.

  ##### AllClasses Command (3)

  Returns reference types for all classes currently loaded by the target VM.
  Out Data
    (None)
  Reply Data

    int | classes | Number of reference types that follow.
    Repeated classes times:
    | byte | refTypeTag | Kind of following reference type.
    | referenceTypeID | typeID | Loaded reference type
    | string | signature | The JNI signature of the loaded reference type
    | int | status | The current class status.

  ##### AllThreads Command (4)

  Returns all threads currently running in the target VM . The returned list contains threads created through java.lang.Thread, all native threads attached to the target VM through JNI, and system threads created by the target VM. Threads that have not yet been started and threads that have completed their execution are not included in the returned list.
  Out Data
    (None)
  Reply Data

    int | threads | Number of threads that follow.
    Repeated threads times:
    | threadID | thread | A running thread

  ##### TopLevelThreadGroups Command (5)

  Returns all thread groups that do not have a parent. This command may be used as the first step in building a tree (or trees) of the existing thread groups.
  Out Data
    (None)
  Reply Data

    int | groups | Number of thread groups that follow.
    Repeated groups times:
    | threadGroupID | group | A top level thread group

  ##### Dispose Command (6)

  Invalidates this virtual machine mirror. The communication channel to the target VM is closed, and the target VM prepares to accept another subsequent connection from this debugger or another debugger, including the following tasks:
  - All event requests are cancelled.
  - All threads suspended by the thread-level resume command or the VM-level resume command are resumed as many times as necessary for them to run.
  - Garbage collection is re-enabled in all cases where it was disabled
  Any current method invocations executing in the target VM are continued after the disconnection. Upon completion of any such method invocation, the invoking thread continues from the location where it was originally stopped.

  Resources originating in this VirtualMachine (ObjectReferences, ReferenceTypes, etc.) will become invalid.

  Out Data
    (None)
  Reply Data
    (None)

  ##### IDSizes Command (7)

  Returns the sizes of variably-sized data types in the target VM.The returned values indicate the number of bytes used by the identifiers in command and reply packets.
  Out Data
    (None)
  Reply Data

    int | fieldIDSize | fieldID size in bytes
    int | methodIDSize | methodID size in bytes
    int | objectIDSize | objectID size in bytes
    int | referenceTypeIDSize | referenceTypeID size in bytes
    int | frameIDSize | frameID size in bytes

  ##### Suspend Command (8)

  Suspends the execution of the application running in the target VM. All Java threads currently running will be suspended.

  Unlike java.lang.Thread.suspend, suspends of both the virtual machine and individual threads are counted. Before a thread will run again, it must be resumed through the VM-level resume command or the thread-level resume command the same number of times it has been suspended.

  Out Data
    (None)
  Reply Data
    (None)

  ##### Resume Command (9)

  Resumes execution of the application after the suspend command or an event has stopped it. Suspensions of the Virtual Machine and individual threads are counted. If a particular thread is suspended n times, it must resumed n times before it will continue.
  Out Data
    (None)
  Reply Data
    (None)

  ##### Exit Command (10)

  Terminates the target VM with the given exit code. All ids previously returned from the target VM become invalid. Threads running in the VM are abruptly terminated. A thread death exception is not thrown and finally blocks are not run.
  Out Data

    int | exitCode | the exit code

  Reply Data
    (None)

  ##### CreateString Command (11)

  Creates a new string object in the target VM and returns its id.
  Out Data

    string | utf | UTF-8 characters to use in the created string.

  Reply Data

    stringID | stringObject | Created string (instance of java.lang.String)

  ##### Capabilities Command (12)

  Retrieve this VM's capabilities. The capabilities are returned as booleans, each indicating the presence or absence of a capability. The commands associated with each capability will return the NOT_IMPLEMENTED error if the cabability is not available.
  Out Data
    (None)
  Reply Data

    boolean | canWatchFieldModification | Can the VM watch field modification, and therefore can it send the Modification Watchpoint Event?
    boolean | canWatchFieldAccess | Can the VM watch field access, and therefore can it send the Access Watchpoint Event?
    boolean | canGetBytecodes | Can the VM get the bytecodes of a given method?
    boolean | canGetSyntheticAttribute | Can the VM determine whether a field or method is synthetic? (that is, can the VM determine if the method or the field was invented by the compiler?)
    boolean | canGetOwnedMonitorInfo | Can the VM get the owned monitors infornation for a thread?
    boolean | canGetCurrentContendedMonitor | Can the VM get the current contended monitor of a thread?
    boolean | canGetMonitorInfo | Can the VM get the monitor information for a given object?

  ##### ClassPaths Command (13)

  Retrieve the classpath and bootclasspath of the target VM. If the classpath is not defined, returns an empty list. If the bootclasspath is not defined returns an empty list.
  Out Data
    (None)
  Reply Data

    string | baseDir | Base directory used to resolve relative paths in either of the following lists.
    int | classpaths | Number of paths in classpath.
    Repeated classpaths times:
    | string | path | One component of classpath
    int | bootclasspaths | Number of paths in bootclasspath.
    Repeated bootclasspaths times:
    | string | path | One component of bootclasspath

  ##### DisposeObjects Command (14)

  Releases a list of object IDs. For each object in the list, the following applies. No further commands will be sent with the object's ID in the list. If the object has not yet been garbage collected, any back-end resources associated with the ID will be freed, and if garbage collection was disabled for the object, it will be re-enabled.

  Use of this command is not required. If it is not sent, resources associated with each ID will be freed by the back-end at some time after the corresponding object is garbage collected. It is most useful to use this command to reduce the load on the back-end if a very large number of objects has been retrieved from the back-end (a large array, for example) but may not be garbage collected any time soon.

  The object IDs may be re-used by the back end after they have been disposed with this command.

  Out Data

    int | requests | Number of object dispose requests that follow
    Repeated requests times:
    | objectID | object | The object ID
    | int | refCnt | The number of times this object ID has been part of a packet received from the back-end. An accurate count prevents the object ID from being freed on the back-end if it is part of an incoming packet, not yet handled by the front-end.

  Reply Data
    (None)

  ##### HoldEvents Command (15)

  Tells the target VM to stop sending events. Events are not discarded; they are held until a subsequent ReleaseEvents command is sent. This command is useful to control the number of events sent to the debugger VM in situations where very large numbers of events are generated. While events are held by the debugger back-end, application execution may be frozen by the debugger back-end to prevent buffer overflows on the back end. Responses to commands are never held and are not affected by this command. If events are already being held, this command is ignored.
  Out Data
    (None)
  Reply Data
    (None)

  ##### ReleaseEvents Command (16)

  Tells the target VM to continue sending events. This command is used to restore normal activity after a HoldEvents command. If there is no current HoldEvents command in effect, this command is ignored.
  Out Data
    (None)
  Reply Data
    (None)

  #### ReferenceType Command Set (2)

  ##### Signature Command (1)

  Returns the JNI signature of a reference type. JNI signature formats are described in the Java Native Inteface Specification

  For primitive classes the returned signature is the signature of the corresponding primitive type; for example, "I" is returned as the signature of the class represented by java.lang.Integer.TYPE.

  Out Data

    referenceTypeID | refType | The reference type ID.

  Reply Data

    string | signature | The JNI signature for the reference type.

  ##### ClassLoader Command (2)

  Returns the instance of java.lang.ClassLoader which loaded a given reference type. If the reference type was loaded by the system class loader, the returned object ID is null.
  Out Data

    referenceTypeID | refType | The reference type ID.

  Reply Data

    classLoaderID | classLoader | The class loader for the reference type.

  ##### Modifiers Command (3)

  Returns the modifiers (also known as access flags) for a reference type. The returned bit mask contains information on the declaration of the reference type. If the reference type is an array or a primitive class (for example, java.lang.Integer.TYPE), the value of the returned bit mask is undefined.
  Out Data

    referenceTypeID | refType | The reference type ID.

  Reply Data

    int | modBits | Modifier bits as defined in the VM Specification

  ##### Fields Command (4)

  Returns information for each field in a reference type. Inherited fields are not included. The field list will include any synthetic fields created by the compiler. Fields are returned in the order they occur in the class file.
  Out Data

    referenceTypeID | refType | The reference type ID.

  Reply Data

    int | declared | Number of declared fields.
    Repeated declared times:
    | fieldID | fieldID | Field ID.
    | string | name | Name of field.
    | string | signature | JNI Signature of field.
    | int | modBits | The modifier bit flags (also known as access flags) which provide additional information on the field declaration. Individual flag values are defined in the VM Specification.In addition, The `0xf0000000` bit identifies the field as synthetic, if the synthetic attribute capability is available.

  ##### Methods Command (5)

  Returns information for each method in a reference type. Inherited methodss are not included. The list of methods will include constructors (identified with the name "<init>"), the initialization method (identified with the name "<clinit>") if present, and any synthetic methods created by the compiler. Methods are returned in the order they occur in the class file.
  Out Data

    referenceTypeID | refType | The reference type ID.

  Reply Data

    int | declared | Number of declared methods.
    Repeated declared times:
    | methodID | methodID | Method ID.
    | string | name | Name of method.
    | string | signature | JNI signature of method.
    | int | modBits | The modifier bit flags (also known as access flags) which provide additional information on the method declaration. Individual flag values are defined in the VM Specification.In addition, The `0xf0000000` bit identifies the method as synthetic, if the synthetic attribute capability is available.

  ##### GetValues Command (6)

  Returns the value of one or more static fields of the reference type. Each field must be member of the reference type or one of its superclasses, superinterfaces, or implemented interfaces. Access control is not enforced; for example, the values of private fields can be obtained.
  Out Data

    referenceTypeID | refType | The reference type ID.
    int | fields | The number of values to get
    Repeated fields times:
    | fieldID | fieldID | A field to get

  Reply Data

    int | values | The number of values returned
    Repeated values times:
    | value | value | The field value

  ##### SourceFile Command (7)

  Returns the name of source file in which a reference type was declared.
  Out Data

    referenceTypeID | refType | The reference type ID.

  Reply Data

    string | sourceFile | The source file name. No path information for the file is included

  ##### NestedTypes Command (8)

  Returns the classes and interfaces directly nested within this type.Types further nested within those types are not included.
  Out Data

    referenceTypeID | refType | The reference type ID.

  Reply Data

    int | classes | The number of nested classes and interfaces
    Repeated classes times:
    | byte | refTypeTag | Kind of following reference type.
    | referenceTypeID | typeID | The nested class or interface ID.

  ##### Status Command (9)

  Returns the current status of the reference type. The status indicates the extent to which the reference type has been initialized, as described in the VM specification. The returned status bits are undefined for array types and for primitive classes (such as java.lang.Integer.TYPE).
  Out Data

    referenceTypeID | refType | The reference type ID.

  Reply Data

    int | status | Status bits:See JDWP.ClassStatus

  ##### Interfaces Command (10)

  Returns the interfaces declared as implemented by this class. Interfaces indirectly implemented (extended by the implemented interface or implemented by a superclass) are not included.
  Out Data

    referenceTypeID | refType | The reference type ID.

  Reply Data

    int | interfaces | The number of implemented interfaces
    Repeated interfaces times:
    | interfaceID | interfaceType | implemented interface.

  ##### ClassObject Command (11)

  Returns the class object corresponding to this type.
  Out Data

    referenceTypeID | refType | The reference type ID.

  Reply Data

    classObjectID | classObject | class object.

  #### ClassType Command Set (3)

  ##### Superclass Command (1)

  Returns the immediate superclass of a class.
  Out Data

    classID | clazz | The class type ID.

  Reply Data

    classID | superclass | The superclass (null if the class ID for java.lang.Object is specified).

  ##### SetValues Command (2)

  Sets the value of one or more static fields. Each field must be member of the class type or one of its superclasses, superinterfaces, or implemented interfaces. Access control is not enforced; for example, the values of private fields can be set. Final fields cannot be set.For primitive values, the value's type must match the field's type exactly. For object values, there must exist a widening reference conversion from the value's type to the field's type and the field's type must be loaded.
  Out Data

    classID | clazz | The class type ID.
    int | values | The number of fields to set.
    Repeated values times:
    | fieldID | fieldID | Field to set.
    | untagged-value | value | Value to put in the field.

  Reply Data
    (None)

  ##### InvokeMethod Command (3)

  Invokes a static method. The method must be member of the class type or one of its superclasses, superinterfaces, or implemented interfaces. Access control is not enforced; for example, private methods can be invoked.

  The method invocation will occur in the specified thread. Method invocation can occur only if the specified thread has been suspended by an event. Method invocation is not supported when the target VM has been suspended by the front-end.

  The specified method is invoked with the arguments in the specified argument list. The method invocation is synchronous; the reply packet is not sent until the invoked method returns in the target VM. The return value (possibly the void value) is included in the reply packet. If the invoked method throws an exception, the exception object ID is set in the reply packet; otherwise, the exception object ID is null.

  For primitive arguments, the argument value's type must match the argument's type exactly. For object arguments, there must exist a widening reference conversion from the argument value's type to the argument's type and the argument's type must be loaded.

  By default, all threads in the target VM are resumed while the method is being invoked if they were previously suspended by an event or by command. This is done to prevent the deadlocks that will occur if any of the threads own monitors that will be needed by the invoked method. It is possible that breakpoints or other events might occur during the invocation. Note, however, that this implicit resume acts exactly like the ThreadReference resume command, so if the thread's suspend count is greater than 1, it will remain in a suspended state during the invocation. By default, when the invocation completes, all threads in the target VM are suspended, regardless their state before the invocation.

  The resumption of other threads during the invoke can be prevented by specifying the INVOKE_SINGLE_THREADED bit flag in the `options` field; however, there is no protection against or recovery from the deadlocks described above, so this option should be used with great caution. Only the specified thread will be resumed (as described for all threads above). Upon completion of a single threaded invoke, the invoking thread will be suspended once again. Note that any threads started during the single threaded invocation will not be suspended when the invocation completes.

  If the target VM is disconnected during the invoke (for example, through the VirtualMachine dispose command) the method invocation continues.

  Out Data

    classID | clazz | The class type ID.
    threadID | thread | The thread in which to invoke.
    methodID | method | The method to invoke.
    int | arguments |
    Repeated arguments times:
    | value | arg | The argument value.
    int | options | Invocation options

  Reply Data

    value | returnValue | The returned value.
    tagged-objectID | exception | The thrown exception.

  ##### NewInstance Command (4)

  Creates a new object of this type, invoking the specified constructor. The constructor method ID must be a member of the class type.

  Instance creation will occur in the specified thread. Instance creation can occur only if the specified thread has been suspended by an event. Method invocation is not supported when the target VM has been suspended by the front-end.

  The specified constructor is invoked with the arguments in the specified argument list. The constructor invocation is synchronous; the reply packet is not sent until the invoked method returns in the target VM. The return value (possibly the void value) is included in the reply packet. If the constructor throws an exception, the exception object ID is set in the reply packet; otherwise, the exception object ID is null.

  For primitive arguments, the argument value's type must match the argument's type exactly. For object arguments, there must exist a widening reference conversion from the argument value's type to the argument's type and the argument's type must be loaded.

  By default, all threads in the target VM are resumed while the method is being invoked if they were previously suspended by an event or by command. This is done to prevent the deadlocks that will occur if any of the threads own monitors that will be needed by the invoked method. It is possible that breakpoints or other events might occur during the invocation. Note, however, that this implicit resume acts exactly like the ThreadReference resume command, so if the thread's suspend count is greater than 1, it will remain in a suspended state during the invocation. By default, when the invocation completes, all threads in the target VM are suspended, regardless their state before the invocation.

  The resumption of other threads during the invoke can be prevented by specifying the INVOKE_SINGLE_THREADED bit flag in the `options` field; however, there is no protection against or recovery from the deadlocks described above, so this option should be used with great caution. Only the specified thread will be resumed (as described for all threads above). Upon completion of a single threaded invoke, the invoking thread will be suspended once again. Note that any threads started during the single threaded invocation will not be suspended when the invocation completes.

  If the target VM is disconnected during the invoke (for example, through the VirtualMachine dispose command) the method invocation continues.

  Out Data

    classID | clazz | The class type ID.
    threadID | thread | The thread in which to invoke the constructor.
    methodID | method | The constructor to invoke.
    int | arguments |
    Repeated arguments times:
    | value | arg | The argument value.
    int | options | Constructor invocation options

  Reply Data

    tagged-objectID | newObject | The newly created object, or null if the constructor threw an exception.
    tagged-objectID | exception | The thrown exception, if any; otherwise, null.

  #### ArrayType Command Set (4)

  ##### NewInstance Command (1)

  Creates a new array object of this type with a given length.
  Out Data

    arrayID | arrType | The array type of the new instance.
    int | length | The length of the array.

  Reply Data

    tagged-objectID | newArray | The newly created array object.

  #### InterfaceType Command Set (5)

  #### Method Command Set (6)

  ##### LineTable Command (1)

  Returns line number information for the method. The line table maps source line numbers to the initial code index of the line. The line table is ordered by code index (from lowest to highest).
  Out Data

    referenceTypeID | classID | The class.
    methodID | methodID | The method.

  Reply Data

    long | start | Lowest valid code index for the method.
    long | end | Highest valid code index for the method.
    int | lines | The number of lines.
    Repeated lines times:
    | long | lineCodeIndex | Initial code index of the line (unsigned).
    | int | lineNumber | Line number.

  ##### VariableTable Command (2)

  Returns variable information for the method. The variable table includes arguments and locals declared within the method. For instance methods, the "this" reference is included in the table. Also, synthetic variables may be present.
  Out Data

    referenceTypeID | classID | The class.
    methodID | methodID | The method.

  Reply Data

    int | argCnt | The number of words in the frame used by arguments. Eight-byte arguments use two words; all others use one.
    int | slots | The number of variables.
    Repeated slots times:
    | long | codeIndex | First code index at which the variable is visible (unsigned). Used in conjunction with `length`. The variable can be get or set only when the current `codeIndex` <= current frame code index < `codeIndex + length`
    | string | name | The variable's name.
    | string | signature | The variable type's JNI signature.
    | int | length | Unsigned value used in conjunction with `codeIndex`. The variable can be get or set only when the current `codeIndex` <= current frame code index < `code index + length`
    | int | slot | The local variable's index in its frame

  ##### Bytecodes Command (3)

  Retrieve the method's bytecodes as defined in the JVM Specification.
  Out Data

    referenceTypeID | classID | The class.
    methodID | methodID | The method.

  Reply Data

    int | bytes |
    Repeated bytes times:
    | byte | bytecode | A Java bytecode.

  #### Field Command Set (8)

  #### ObjectReference Command Set (9)

  ##### ReferenceType Command (1)

  Returns the runtime type of the object. The runtime type will be a class or an array.
  Out Data

    objectID | object | The object ID

  Reply Data

    byte | refTypeTag | Kind of following reference type.
    referenceTypeID | typeID | The runtime reference type.

  ##### GetValues Command (2)

  Returns the value of one or more instance fields. Each field must be member of the object's type or one of its superclasses, superinterfaces, or implemented interfaces. Access control is not enforced; for example, the values of private fields can be obtained.
  Out Data

    objectID | object | The object ID
    int | fields | The number of values to get
    Repeated fields times:
    | fieldID | fieldID | Field to get.

  Reply Data

    int | values | The number of values returned
    Repeated values times:
    | value | value | The field value

  ##### SetValues Command (3)

  Sets the value of one or more instance fields. Each field must be member of the object's type or one of its superclasses, superinterfaces, or implemented interfaces. Access control is not enforced; for example, the values of private fields can be set. For primitive values, the value's type must match the field's type exactly. For object values, there must be a widening reference conversion from the value's type to the field's type and the field's type must be loaded.
  Out Data

    objectID | object | The object ID
    int | values | The number of fields to set.
    Repeated values times:
    | fieldID | fieldID | Field to set.
    | untagged-value | value | Value to put in the field.

  Reply Data
    (None)

  ##### MonitorInfo Command (5)

  Returns monitor information for an object. All threads int the VM must be suspended.
  Out Data

    objectID | object | The object ID

  Reply Data

    threadID | owner | The monitor owner, or null if it is not currently owned.
    int | entryCount | The number of times the monitor has been entered.
    int | waiters | The number of threads that are waiting for the monitor 0 if there is no current owner
    Repeated waiters times:
    | threadID | thread | A thread waiting for this monitor.

  ##### InvokeMethod Command (6)

  Invokes a instance method. The method must be member of the object's type or one of its superclasses, superinterfaces, or implemented interfaces. Access control is not enforced; for example, private methods can be invoked.

  The method invocation will occur in the specified thread. Method invocation can occur only if the specified thread has been suspended by an event. Method invocation is not supported when the target VM has been suspended by the front-end.

  The specified method is invoked with the arguments in the specified argument list. The method invocation is synchronous; the reply packet is not sent until the invoked method returns in the target VM. The return value (possibly the void value) is included in the reply packet. If the invoked method throws an exception, the exception object ID is set in the reply packet; otherwise, the exception object ID is null.

  For primitive arguments, the argument value's type must match the argument's type exactly. For object arguments, there must be a widening reference conversion from the argument value's type to the argument's type and the argument's type must be loaded.

  By default, all threads in the target VM are resumed while the method is being invoked if they were previously suspended by an event or by command. This is done to prevent the deadlocks that will occur if any of the threads own monitors that will be needed by the invoked method. It is possible that breakpoints or other events might occur during the invocation. Note, however, that this implicit resume acts exactly like the ThreadReference resume command, so if the thread's suspend count is greater than 1, it will remain in a suspended state during the invocation. By default, when the invocation completes, all threads in the target VM are suspended, regardless their state before the invocation.

  The resumption of other threads during the invoke can be prevented by specifying the INVOKE_SINGLE_THREADED bit flag in the `options` field; however, there is no protection against or recovery from the deadlocks described above, so this option should be used with great caution. Only the specified thread will be resumed (as described for all threads above). Upon completion of a single threaded invoke, the invoking thread will be suspended once again. Note that any threads started during the single threaded invocation will not be suspended when the invocation completes.

  If the target VM is disconnected during the invoke (for example, through the VirtualMachine dispose command) the method invocation continues.

  Out Data

    objectID | object | The object ID
    threadID | thread | The thread in which to invoke.
    classID | clazz | The class type.
    methodID | method | The method to invoke.
    int | arguments | The number of arguments.
    Repeated arguments times:
    | value | arg | The argument value.
    int | options | Invocation options

  Reply Data

    value | returnValue | The returned value, or null if an exception is thrown.
    tagged-objectID | exception | The thrown exception, if any.

  ##### DisableCollection Command (7)

  Prevents garbage collection for the given object. By default all objects in back-end replies may be collected at any time the target VM is running. A call to this command guarantees that the object will not be collected. The EnableCollection command can be used to allow collection once again.

  Note that while the target VM is suspended, no garbage collection will occur because all threads are suspended. The typical examination of variables, fields, and arrays during the suspension is safe without explicitly disabling garbage collection.

  This method should be used sparingly, as it alters the pattern of garbage collection in the target VM and, consequently, may result in application behavior under the debugger that differs from its non-debugged behavior.

  Out Data

    objectID | object | The object ID

  Reply Data
    (None)

  ##### EnableCollection Command (8)

  Permits garbage collection for this object. By default all objects returned by the JDWP may be collected at any time the target VM is running. A call to this command is necessary only if garbage collection was previously disabled with the DisableCollection command.
  Out Data

    objectID | object | The object ID

  Reply Data
    (None)

  ##### IsCollected Command (9)

  Determines whether an object has been garbage collected in the target VM.
  Out Data

    objectID | object | The object ID

  Reply Data

    boolean | isCollected | true if the object has been collected; false otherwise

  #### StringReference Command Set (10)

  ##### Value Command (1)

  Returns the characters contained in the string.
  Out Data

    objectID | stringObject | The String object ID.

  Reply Data

    string | stringValue | The value of the String.

  #### ThreadReference Command Set (11)

  ##### Name Command (1)

  Returns the thread name.
  Out Data

    threadID | threadObject | The thread object ID.

  Reply Data

    string | threadName | The thread name.

  ##### Suspend Command (2)

  Suspends the thread.

  Unlike java.lang.Thread.suspend(), suspends of both the virtual machine and individual threads are counted. Before a thread will run again, it must be resumed the same number of times it has been suspended.

  Suspending single threads with command has the same dangers java.lang.Thread.suspend(). If the suspended thread holds a monitor needed by another running thread, deadlock is possible in the target VM (at least until the suspended thread is resumed again).

  The suspended thread is guaranteed to remain suspended until resumed through one of the JDI resume methods mentioned above; the application in the target VM cannot resume the suspended thread through {@link java.lang.Thread#resume}.

  Note that this doesn't change the status of the thread (see the ThreadStatus command.) For example, if it was Running, it will still appear running to other threads.

  Out Data

    threadID | threadObject | The thread object ID.

  Reply Data
    (None)

  ##### Resume Command (3)

  Resumes the execution of a given thread. If this thread was not previously suspended by the front-end, calling this command has no effect. Otherwise, the count of pending suspends on this thread is decremented. If it is decremented to 0, the thread will continue to execute.
  Out Data

    threadID | threadObject | The thread object ID.

  Reply Data
    (None)

  ##### Status Command (4)

  Returns the current status of a thread. The thread status reply indicates the thread status the last time it was running. the suspend status provides information on the thread's suspension, if any.
  Out Data

    threadID | threadObject | The thread object ID.

  Reply Data

    int | threadStatus | One of the thread status codes See JDWP.ThreadStatus
    int | suspendStatus | One of the suspend status codes See JDWP.SuspendStatus

  ##### ThreadGroup Command (5)

  Returns the thread group that contains a given thread.
  Out Data

    threadID | threadObject | The thread object ID.

  Reply Data

    threadGroupID | group | The thread group of this thread.

  ##### Frames Command (6)

  Returns the current call stack of a suspended thread. The sequence of frames starts with the currently executing frame, followed by its caller, and so on. The thread must be suspended, and the returned frameID is valid only while the thread is suspended.
  Out Data

    threadID | threadObject | The thread object ID.
    int | startFrame | The index of the first frame to retrieve.
    int | length | The count of frames to retrieve (-1 means all remaining).

  Reply Data

    int | frames | The number of frames retreived
    Repeated frames times:
    | frameID | frameID | The ID of this frame.
    | location | location | The current location of this frame

  ##### FrameCount Command (7)

  Returns the count of frames on this thread's stack. The thread must be suspended, and the returned count is valid only while the thread is suspended. Returns JDWP.Error.errorThreadNotSuspended if not suspended.
  Out Data

    threadID | threadObject | The thread object ID.

  Reply Data

    int | frameCount | The count of frames on this thread's stack.

  ##### OwnedMonitors Command (8)

  Returns the objects whose monitors have been entered by this thread. The thread must be suspended, and the returned information is relevant only while the thread is suspended.
  Out Data

    threadID | threadObject | The thread object ID.

  Reply Data

    int | owned | The number of owned monitors
    Repeated owned times:
    | tagged-objectID | monitor | An owned monitor

  ##### CurrentContendedMonitor Command (9)

  Returns the object, if any, for which this thread is waiting for monitor entry or with java.lang.Object.wait. The thread must be suspended, and the returned information is relevant only while the thread is suspended.
  Out Data

    threadID | threadObject | The thread object ID.

  Reply Data

    tagged-objectID | monitor | The contended monitor, or null if there is no current contended monitor.

  ##### Stop Command (10)

  Stops the thread with an asynchronous exception, as if done by java.lang.Thread.stop
  Out Data

    threadID | threadObject | The thread object ID.
    objectID | throwable | Asynchronous exception. This object must be an instance of java.lang.Throwable or a subclass

  Reply Data
    (None)

  ##### Interrupt Command (11)

  Interrupt the thread, as if done by java.lang.Thread.interrupt
  Out Data

    threadID | threadObject | The thread object ID.

  Reply Data
    (None)

  ##### SuspendCount Command (12)

  Get the suspend count for this thread. The suspend count is the number of times the thread has been suspended through the thread-level or VM-level suspend commands without a corresponding resume
  Out Data

    threadID | threadObject | The thread object ID.

  Reply Data

    int | suspendCount | The number of outstanding suspends of this thread.

  #### ThreadGroupReference Command Set (12)

  ##### Name Command (1)

  Returns the thread group name.
  Out Data

    threadGroupID | group | The thread group object ID.

  Reply Data

    string | groupName | The thread group's name.

  ##### Parent Command (2)

  Returns the thread group, if any, which contains a given thread group.
  Out Data

    threadGroupID | group | The thread group object ID.

  Reply Data

    threadGroupID | parentGroup | The parent thread group object, or null if the given thread group is a top-level thread group

  ##### Children Command (3)

  Returns the threads and thread groups directly contained in this thread group. Threads and thread groups in child thread groups are not included.
  Out Data

    threadGroupID | group | The thread group object ID.

  Reply Data

    int | childThreads | The number of child threads.
    Repeated childThreads times:
    | threadID | childThread | A direct child thread ID.
    int | childGroups | The number of child thread groups.
    Repeated childGroups times:
    | threadGroupID | childGroup | A direct child thread group ID.

  #### ArrayReference Command Set (13)

  ##### Length Command (1)

  Returns the number of components in a given array.
  Out Data

    arrayID | arrayObject | The array object ID.

  Reply Data

    int | arrayLength | The length of the array.

  ##### GetValues Command (2)

  Returns a range of array components. The specified range must be within the bounds of the array.
  Out Data

    arrayID | arrayObject | The array object ID.
    int | firstIndex | The first index to retrieve.
    int | length | The number of components to retrieve.

  Reply Data

    arrayregion | values | The retrieved values. If the values are objects, they are tagged-values; otherwise, they are untagged-values

  ##### SetValues Command (3)

  Sets a range of array components. The specified range must be within the bounds of the array. For primitive values, each value's type must match the array component type exactly. For object values, there must be a widening reference conversion from the value's type to the array component type and the array component type must be loaded.
  Out Data

    arrayID | arrayObject | The array object ID.
    int | firstIndex | The first index to set.
    int | values | The number of values to set.
    Repeated values times:
    | untagged-value | value | A value to set.

  Reply Data
    (None)

  #### ClassLoaderReference Command Set (14)

  ##### VisibleClasses Command (1)

  Returns a list of all classes which this class loader has been requested to load. This class loader is considered to be an initiating class loader for each class in the returned list. The list contains each reference type defined by this loader and any types for which loading was delegated by this class loader to another class loader.

  The visible class list has useful properties with respect to the type namespace. A particular type name will occur at most once in the list. Each field or variable declared with that type name in a class defined by this class loader must be resolved to that single type.

  No ordering of the returned list is guaranteed.

  Out Data

    classLoaderID | classLoaderObject | The class loader object ID.

  Reply Data

    int | classes | The number of visible classes.
    Repeated classes times:
    | byte | refTypeTag | Kind of following reference type.
    | referenceTypeID | typeID | A class visible to this class loader.

  #### EventRequest Command Set (15)

  ##### Set Command (1)

  Set an event request. When the event described by this request occurs, an event is sent from the target VM.
  Out Data

    byte | eventKind | Event kind to request. See JDWP.EventKind for a complete list of events that can be requested.
    byte | suspendPolicy | What threads are suspended when this event occurs? Note that the order of events and command replies accurately reflects the order in which threads are suspended and resumed. For example, if a VM-wide resume is processed before an event occurs which suspends the VM, the reply to the resume command will be written to the transport before the suspending event.
    int | modifiers | Constraints used to control the number of generated events. Modifiers specify additional tests that an event must satisfy before it is placed in the event queue. Events are filtered by applying each modifier to an event in the order they are specified in this collection Only events that satisfy all modifiers are reported. Filtering can improve debugger performance dramatically by reducing the amount of event traffic sent from the target VM to the debugger VM.
    Repeated modifiers times:
    | byte | modKind | Modifier kind
    | Case Count - if modKind is 1: | Limit the requested event to be reported at most once after a given number of occurrences. The event is not reported the first `count - 1` times this filter is reached. To request a one-off event, call this method with a count of 1. Once the count reaches 0, any subsequent filters in this request are applied. If none of those filters cause the event to be suppressed, the event is reported. Otherwise, the event is not reported. In either case subsequent events are never reported for this request. This modifier can be used with any event kind.
    | int | count | Count before event. One for one-off.
    | Case Conditional - if modKind is 2: | Conditional on expression
    | int | exprID | For the future
    | Case ThreadOnly - if modKind is 3: | Restricts reported events to those in the given thread. This modifier can be used with any event kind except for class unload.
    | threadID | thread | Required thread
    | Case ClassOnly - if modKind is 4: | For class prepare events, restricts the events generated by this request to be the preparation of the given reference type and any subtypes. For other events, restricts the events generated by this request to those whose location is in the given reference type or any of its subtypes. An event will be generated for any location in a reference type that can be safely cast to the given reference type. This modifier can be used with any event kind except class unload, thread start, and thread end.
    | referenceTypeID | clazz | Required class
    | Case ClassMatch - if modKind is 5: | Restricts reported events to those for classes whose name matches the given restricted regular expression. For class prepare events, the prepared class name is matched. For class unload events, the unloaded class name is matched. For other events, the class name of the event's location is matched. This modifier can be used with any event kind except thread start and thread end.
    | string | classPattern | Required class pattern. Matches are limited to exact matches of the given class pattern and matches of patterns that begin or end with '*'; for example, "*.Foo" or "java.*".
    | Case ClassExclude - if modKind is 6: | Restricts reported events to those for classes whose name does not match the given restricted regular expression. For class prepare events, the prepared class name is matched. For class unload events, the unloaded class name is matched. For other events, the class name of the event's location is matched. This modifier can be used with any event kind except thread start and thread end.
    | string | classPattern | Disallowed class pattern. Matches are limited to exact matches of the given class pattern and matches of patterns that begin or end with '*'; for example, "*.Foo" or "java.*".
    | Case LocationOnly - if modKind is 7: | Restricts reported events to those that occur at the given location. This modifier can be used with breakpoint, field access, field modification, step, and exception event kinds.
    | location | loc | Required location
    | Case ExceptionOnly - if modKind is 8: | Restricts reported exceptions by their class and whether they are caught or uncaught. This modifier can be used with exception event kinds only.
    | referenceTypeID | exceptionOrNull | Exception to report. Null (0) means report exceptions of all types. A non-null type restricts the reported exception events to exceptions of the given type or any of its subtypes.
    | boolean | caught | Report caught exceptions
    | boolean | uncaught | Report uncaught exceptions. Note that it is not always possible to determine whether an exception is caught or uncaught at the time it is thrown. See the exception event catch location under composite events for more information.
    | Case FieldOnly - if modKind is 9: | Restricts reported events to those that occur for a given field. This modifier can be used with field access and field modification event kinds only.
    | referenceTypeID | declaring | Type in which field is declared.
    | fieldID | fieldID | Required field
    | Case Step - if modKind is 10: | Restricts reported step events to those which satisfy depth and size constraints. This modifier can be used with step event kinds only.
    | threadID | thread | Thread in which to step
    | int | size | size of each step. See JDWP.StepSize
    | int | depth | relative call stack limit. See JDWP.StepDepth

  Reply Data

    int | requestID | ID of created request

  ##### Clear Command (2)

  Clear an event request.
  Out Data

    byte | event | Event type to clear
    int | requestID | ID of request to clear

  Reply Data
    (None)

  ##### ClearAllBreakpoints Command (3)

  Removes all set breakpoints.
  Out Data
    (None)
  Reply Data
    (None)

  #### StackFrame Command Set (16)

  ##### GetValues Command (1)

  Returns the value of one or more local variables in a given frame. Each variable must be visible at the frame's code index. Even if local variable information is not available, values can be retrieved if the front-end is able to determine the correct local variable index. (Typically, this index can be determined for method arguments from the method signature without access to the local variable table information.)
  Out Data

    threadID | threadObject | The frame's thread.
    frameID | frame | The frame ID.
    int | slots | The number of values to get.
    Repeated slots times:
    | int | slot | The local variable's index in the frame.
    | byte | sigbyte | A tag identifying the type of the variable

  Reply Data

    int | values | The number of values retrieved.
    Repeated values times:
    | value | slotValue | The value of the local variable.

  ##### SetValues Command (2)

  Sets the value of one or more local variables. Each variable must be visible at the current frame code index. For primitive values, the value's type must match the variable's type exactly. For object values, there must be a widening reference conversion from the value's type to the variable's type and the variable's type must be loaded.

  Even if local variable information is not available, values can be set, if the front-end is able to determine the correct local variable index. (Typically, this index can be determined for method arguments from the method signature without access to the local variable table information.)

  Out Data

    threadID | threadObject | The frame's thread.
    frameID | frame | The frame ID.
    int | slotValues | The number of values to set.
    Repeated slotValues times:
    | int | slot | The slot ID.
    | value | slotValue | The value to set.

  Reply Data
    (None)

  ##### ThisObject Command (3)

  Returns the value of the 'this' reference for this frame. If the frame's method is static or native, the reply will contain the null object reference.
  Out Data

    threadID | threadObject | The frame's thread.
    frameID | frame | The frame ID.

  Reply Data

    tagged-objectID | objectThis | The 'this' object for this frame.

  #### ClassObjectReference Command Set (17)

  ##### ReflectedType Command (1)

  Returns the reference type reflected by this class object.
  Out Data

    classObjectID | classObject | The class object.

  Reply Data

    byte | refTypeTag | Kind of following reference type.
    referenceTypeID | typeID | reflected reference type

  #### Event Command Set (64)

  ##### Composite Command (100)

  Several events may occur at a given time in the target VM. For example, there may be more than one breakpoint request for a given location or you might single step to the same location as a breakpoint request. These events are delivered together as a composite event. For uniformity, a composite event is always used to deliver events, even if there is only one event to report.

  The events that are grouped in a composite event are restricted in the following ways:

  - Always singleton composite events:
    - VM Start Event
    - VM Death Event
  - Only with other thread start events for the same thread:
    - Thread Start Event
  - Only with other thread death events for the same thread:
    - Thread Death Event
  - Only with other class prepare events for the same class:
    - Class Prepare Event}
  - Only with other class unload events for the same class:
    - Class Unload Event
  - Only with other access watchpoint events for the same field access:
    - Access Watchpoint Event
  - Only with other modification watchpoint events for the same field modification:
    - Modification Watchpoint Event
  - Only with other ExceptionEvents for the same exception occurrance:
    - ExceptionEvent
  - Only with other members of this group, at the same location and in the same thread:
    - Breakpoint Event
    - Step Event
    - Method Entry Event
    - Method Exit Event
  Event Data

    byte | suspendPolicy | Which threads where suspended by this composite event?
    int | events | Events in set.
    Repeated events times:
    | byte | eventKind | Event kind selector
    | Case VMStart - if eventKind is JDWP.EventKind.VM_START: | Notification of initialization of a target VM. This event is received before the main thread is started and before any application code has been executed. Before this event occurs a significant amount of system code has executed and a number of system classes have been loaded. This event is always generated by the target VM, even if not explicitly requested.
    | int | requestID | Request that generated event (or 0 if this event is automatically generated.
    | threadID | thread | Initial thread
    | Case SingleStep - if eventKind is JDWP.EventKind.SINGLE_STEP: | Notification of step completion in the target VM. The step event is generated before the code at its location is executed.
    | int | requestID | Request that generated event
    | threadID | thread | Stepped thread
    | location | location | Location stepped to
    | Case Breakpoint - if eventKind is JDWP.EventKind.BREAKPOINT: | Notification of a breakpoint in the target VM. The breakpoint event is generated before the code at its location is executed.
    | int | requestID | Request that generated event
    | threadID | thread | thread which hit breakpoint
    | location | location | Location hit
    | Case MethodEntry - if eventKind is JDWP.EventKind.METHOD_ENTRY: | Notification of a method invocation in the target VM. This event is generated before any code in the invoked method has executed. Method entry events are generated for both native and non-native methods. In some VMs method entry events can occur for a particular thread before its thread start event occurs if methods are called as part of the thread's initialization.
    | int | requestID | Request that generated event
    | threadID | thread | thread which entered method
    | location | location | Location of entry
    | Case MethodExit - if eventKind is JDWP.EventKind.METHOD_EXIT: | Notification of a method return in the target VM. This event is generated after all code in the method has executed, but the location of this event is the last executed location in the method. Method exit events are generated for both native and non-native methods. Method exit events are not generated if the method terminates with a thrown exception.
    | int | requestID | Request that generated event
    | threadID | thread | thread which exited method
    | location | location | Location of exit
    | Case Exception - if eventKind is JDWP.EventKind.EXCEPTION: | Notification of an exception in the target VM. If the exception is thrown from a non-native method, the exception event is generated at the location where the exception is thrown. If the exception is thrown from a native method, the exception event is generated at the first non-native location reached after the exception is thrown.
    | int | requestID | Request that generated event
    | threadID | thread | Thread with exception
    | location | location | Location of exception throw (or first non-native location after throw if thrown from a native method)
    | tagged-objectID | exception | Thrown exception
    | location | catchLocation | Location of catch, or 0 if not caught. An exception is considered to be caught if, at the point of the throw, the current location is dynamically enclosed in a try statement that handles the exception. (See the JVM specification for details). If there is such a try statement, the catch location is the first location in the appropriate catch clause. If there are native methods in the call stack at the time of the exception, there are important restrictions to note about the returned catch location. In such cases, it is not possible to predict whether an exception will be handled by some native method on the call stack. Thus, it is possible that exceptions considered uncaught here will, in fact, be handled by a native method and not cause termination of the target VM. Furthermore, it cannot be assumed that the catch location returned here will ever be reached by the throwing thread. If there is a native frame between the current location and the catch location, the exception might be handled and cleared in that native method instead. Note that compilers can generate try-catch blocks in some cases where they are not explicit in the source code; for example, the code generated for `synchronized` and `finally` blocks can contain implicit try-catch blocks. If such an implicitly generated try-catch is present on the call stack at the time of the throw, the exception will be considered caught even though it appears to be uncaught from examination of the source code.
    | Case ThreadStart - if eventKind is JDWP.EventKind.THREAD_START: | Notification of a new running thread in the target VM. The new thread can be the result of a call to `java.lang.Thread.start` or the result of attaching a new thread to the VM though JNI. The notification is generated by the new thread some time before its execution starts. Because of this timing, it is possible to receive other events for the thread before this event is received. (Notably, Method Entry Events and Method Exit Events might occur during thread initialization. It is also possible for the VirtualMachine AllThreads command to return a thread before its thread start event is received. Note that this event gives no information about the creation of the thread object which may have happened much earlier, depending on the VM being debugged.
    | int | requestID | Request that generated event
    | threadID | thread | Started thread
    | Case ThreadDeath - if eventKind is JDWP.EventKind.THREAD_DEATH: | Notification of a completed thread in the target VM. The notification is generated by the dying thread before it terminates. Because of this timing, it is possible for {@link VirtualMachine#allThreads} to return this thread after this event is received. Note that this event gives no information about the lifetime of the thread object. It may or may not be collected soon depending on what references exist in the target VM.
    | int | requestID | Request that generated event
    | threadID | thread | Ending thread
    | Case ClassPrepare - if eventKind is JDWP.EventKind.CLASS_PREPARE: | Notification of a class prepare in the target VM. See the JVM specification for a definition of class preparation. Class prepare events are not generated for primtiive classes (for example, java.lang.Integer.TYPE).
    | int | requestID | Request that generated event
    | threadID | thread | Preparing thread. In rare cases, this event may occur in a debugger system thread within the target VM. Debugger threads take precautions to prevent these events, but they cannot be avoided under some conditions, especially for some subclasses of java.lang.Error. If the event was generated by a debugger system thread, the value returned by this method is null, and if the requested suspend policy for the event was EVENT_THREAD all threads will be suspended instead, and the composite event's suspend policy will reflect this change. Note that the discussion above does not apply to system threads created by the target VM during its normal (non-debug) operation.
    | byte | refTypeTag | Kind of reference type. See JDWP.TypeTag
    | referenceTypeID | typeID | Type being prepared
    | string | signature | Type signature
    | int | status | Status of type. See JDWP.ClassStatus
    | Case ClassUnload - if eventKind is JDWP.EventKind.CLASS_UNLOAD: | Notification of a class unload in the target VM. There are severe constraints on the debugger back-end during garbage collection, so unload information is greatly limited.
    | int | requestID | Request that generated event
    | string | signature | Type signature
    | Case FieldAccess - if eventKind is JDWP.EventKind.FIELD_ACCESS: | Notification of a field access in the target VM. Field modifications are not considered field accesses.
    | int | requestID | Request that generated event
    | threadID | thread | Accessing thread
    | location | location | Location of access
    | byte | refTypeTag | Kind of reference type. See JDWP.TypeTag
    | referenceTypeID | typeID | Type of field
    | fieldID | fieldID | Field being accessed
    | tagged-objectID | object | Object being accessed (null=0 for statics
    | Case FieldModification - if eventKind is JDWP.EventKind.FIELD_MODIFICATION: | Notification of a field modification in the target VM.
    | int | requestID | Request that generated event
    | threadID | thread | Modifying thread
    | location | location | Location of modify
    | byte | refTypeTag | Kind of reference type. See JDWP.TypeTag
    | referenceTypeID | typeID | Type of field
    | fieldID | fieldID | Field being modified
    | tagged-objectID | object | Object being modified (null=0 for statics
    | value | valueToBe | Value to be assigned
    | Case VMDeath - if eventKind is JDWP.EventKind.VM_DEATH: |
    | int | requestID | Request that generated event (always 0)

  #### Error Constants

    INVALID_TAG | 500 | object type id or class tag
    ALREADY_INVOKING | 502 | previous invoke not complete
    INVALID_INDEX | 503 |
    INVALID_LENGTH | 504 |
    INVALID_STRING | 506 |
    INVALID_CLASS_LOADER | 507 |
    INVALID_ARRAY | 508 |
    TRANSPORT_LOAD | 509 |
    TRANSPORT_INIT | 510 |
    NATIVE_METHOD | 511 |
    INVALID_COUNT | 512 |
    NONE | 0 |
    INVALID_THREAD | 10 |
    INVALID_THREAD_GROUP | 11 |
    INVALID_PRIORITY | 12 |
    THREAD_NOT_SUSPENDED | 13 |
    THREAD_SUSPENDED | 14 |
    INVALID_OBJECT | 20 |
    INVALID_CLASS | 21 |
    CLASS_NOT_PREPARED | 22 |
    INVALID_METHODID | 23 |
    INVALID_LOCATION | 24 |
    INVALID_FIELDID | 25 |
    INVALID_FRAMEID | 30 |
    NO_MORE_FRAMES | 31 |
    OPAQUE_FRAME | 32 |
    NOT_CURRENT_FRAME | 33 |
    TYPE_MISMATCH | 34 |
    INVALID_SLOT | 35 |
    DUPLICATE | 40 |
    NOT_FOUND | 41 |
    INVALID_MONITOR | 50 |
    NOT_MONITOR_OWNER | 51 |
    INTERRUPT | 52 |
    INVALID_CLASS_FORMAT | 60 |
    CIRCULAR_CLASS_DEFINITION | 61 |
    FAILS_VERIFICATION | 62 |
    ADD_METHOD_NOT_IMPLEMENTED | 63 |
    SCHEMA_CHANGE_NOT_IMPLEMENTED | 64 |
    INVALID_TYPESTATE | 65 |
    NOT_IMPLEMENTED | 99 |
    NULL_POINTER | 100 |
    ABSENT_INFORMATION | 101 |
    INVALID_EVENT_TYPE | 102 |
    ILLEGAL_ARGUMENT | 103 |
    OUT_OF_MEMORY | 110 |
    ACCESS_DENIED | 111 |
    VM_DEAD | 112 |
    INTERNAL | 113 |
    UNATTACHED_THREAD | 115 |

    #### EventKind Constants

    VM_DISCONNECTED | 100 | Never sent by across JDWP
    VM_START | JDWP.EventKind.VM_INIT |
    THREAD_DEATH | JDWP.EventKind.THREAD_END |
    SINGLE_STEP | 1 |
    BREAKPOINT | 2 |
    FRAME_POP | 3 |
    EXCEPTION | 4 |
    USER_DEFINED | 5 |
    THREAD_START | 6 |
    THREAD_END | 7 |
    CLASS_PREPARE | 8 |
    CLASS_UNLOAD | 9 |
    CLASS_LOAD | 10 |
    FIELD_ACCESS | 20 |
    FIELD_MODIFICATION | 21 |
    EXCEPTION_CATCH | 30 |
    METHOD_ENTRY | 40 |
    METHOD_EXIT | 41 |
    VM_INIT | 90 |
    VM_DEATH | 99 |

    #### ThreadStatus Constants

    ZOMBIE | 0 |
    RUNNING | 1 |
    SLEEPING | 2 |
    MONITOR | 3 |
    WAIT | 4 |

    #### SuspendStatus Constants

    SUSPEND_STATUS_SUSPENDED | 0x1 |

    #### ClassStatus Constants

    VERIFIED | 1 |
    PREPARED | 2 |
    INITIALIZED | 4 |
    ERROR | 8 |

    #### TypeTag Constants

    CLASS | 1 | ReferenceType is a class.
    INTERFACE | 2 | ReferenceType is an interface.
    ARRAY | 3 | ReferenceType is an array.

    #### Tag Constants

    ARRAY | 91 | '[' - an array object (objectID size).
    BYTE | 66 | 'B' - a byte value (1 byte).
    CHAR | 67 | 'C' - a character value (2 bytes).
    OBJECT | 76 | 'L' - an object (objectID size).
    FLOAT | 70 | 'F' - a float value (4 bytes).
    DOUBLE | 68 | 'D' - a double value (8 bytes).
    INT | 73 | 'I' - an int value (4 bytes).
    LONG | 74 | 'J' - a long value (8 bytes).
    SHORT | 83 | 'S' - a short value (2 bytes).
    VOID | 86 | 'V' - a void value (no bytes).
    BOOLEAN | 90 | 'Z' - a boolean value (1 byte).
    STRING | 115 | 's' - a String object (objectID size).
    THREAD | 116 | 't' - a Thread object (objectID size).
    THREAD_GROUP | 103 | 'g' - a ThreadGroup object (objectID size).
    CLASS_LOADER | 108 | 'l' - a ClassLoader object (objectID size).
    CLASS_OBJECT | 99 | 'c' - a class object object (objectID size).

    #### StepDepth Constants

    INTO | 0 | Step into any method calls that occur before the end of the step.
    OVER | 1 | Step over any method calls that occur before the end of the step.
    OUT | 2 | Step out of the current method.

    #### StepSize Constants

    MIN | 0 | Step by the minimum possible amount (often a bytecode instruction).
    LINE | 1 | Step to the next source line.

    #### SuspendPolicy Constants

    NONE | 0 | Suspend no threads when this event is encountered.
    EVENT_THREAD | 1 | Suspend the event thread when this event is encountered.
    ALL | 2 | Suspend all threads when this event is encountered.

    #### InvokeOptions Constants

    INVOKE_SINGLE_THREADED | 0x01 | otherwise, all threads started.
    INVOKE_NONVIRTUAL | 0x02 | otherwise, normal virtual invoke (instance methods only)

    Copyright © 1997-1999 Sun Microsystems, Inc. All Rights Reserved. Please send comments to: java-debugger@java.sun.com |