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## com.sun.management
Class VMOption

    java.lang.Object
      com.sun.management.VMOption

    public class VMOption

extends Object

Information about a VM option including its value and where the value came from which is referred as its `origin`.

Each VM option has a default value. A VM option can be set at VM creation time typically as a command line argument to the launcher or an argument passed to the VM created using the JNI invocation interface. In addition, a VM option may be set via an environment variable or a configuration file. A VM option can also be set dynamically via a management interface after the VM was started. A `VMOption` contains the value of a VM option and the origin of that value at the time this `VMOption` object was constructed. The value of the VM option may be changed after the `VMOption` object was constructed,

Since:
  1.6
See Also:
  Java Virtual Machine

Nested Class Summary
`static class` | `VMOption.Origin` Origin of the value of a VM option.

Constructor Summary
`VMOption(String name, String value, boolean writeable, VMOption.Origin origin)` Constructs a `VMOption`.

Method Summary
`static VMOption` | `from(CompositeData cd)` Returns a `VMOption` object represented by the given `CompositeData`.
`String` | `getName()` Returns the name of this VM option.
`VMOption.Origin` | `getOrigin()` Returns the origin of the value of this VM option.
`String` | `getValue()` Returns the value of this VM option at the time when this `VMOption` was created.
`boolean` | `isWriteable()` Tests if this VM option is writeable.
`String` | `toString()`

Methods inherited from class java.lang.Object
`clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait`

Constructor Detail

### VMOption

    public VMOption(String name,
                    String value,
                    boolean writeable,
                    VMOption.Origin origin)

  Constructs a `VMOption`.

  Parameters:
    `name` - Name of a VM option.
    `value` - Value of a VM option.
    `writeable` - `true` if a VM option can be set dynamically, or `false` otherwise.
    `origin` - where the value of a VM option came from.
  Throws:
    `NullPointerException` - if the name or value is `null`

Method Detail

### getName

    public String getName()

  Returns the name of this VM option.

  Returns:
    the name of this VM option.

### getValue

    public String getValue()

  Returns the value of this VM option at the time when this `VMOption` was created. The value could have been changed.

  Returns:
    the value of the VM option at the time when this `VMOption` was created.

### getOrigin

    public VMOption.Origin getOrigin()

  Returns the origin of the value of this VM option. That is, where the value of this VM option came from.

  Returns:
    where the value of this VM option came from.

### isWriteable

    public boolean isWriteable()

  Tests if this VM option is writeable. If this VM option is writeable, it can be set by the `HotSpotDiagnosticMXBean.setVMOption` method.

  Returns:
    `true` if this VM option is writeable; `false` otherwise.

### toString

    public String toString()

  Overrides:
    `toString` in class `Object`

### from

    public static VMOption from(CompositeData cd)

  Returns a `VMOption` object represented by the given `CompositeData`. The given `CompositeData` must contain the following attributes:

  > Attribute Name | Type
  > --- | ---
  > name | `java.lang.String`
  > value | `java.lang.String`
  > origin | `java.lang.String`
  > writeable | `java.lang.Boolean`

  Parameters:
    `cd` - `CompositeData` representing a `VMOption`
  Returns:
    a `VMOption` object represented by `cd` if `cd` is not `null`; `null` otherwise.
  Throws:
    `IllegalArgumentException` - if `cd` does not represent a `VMOption` with the attributes described above.

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