/*
 * @(#)SearchControls.java	1.8 01/12/03
 *
 * Copyright 2002 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */


package javax.naming.directory;

/**
  * This class encapsulates
  * factors that determine scope of search and what gets returned
  * as a result of the search.
  *<p>
  * A SearchControls instance is not synchronized against concurrent 
  * multithreaded access. Multiple threads trying to access and modify
  * a single SearchControls instance should lock the object.
  *
  * @author Rosanna Lee
  * @author Scott Seligman
  * @version 1.8 01/12/03
  * @since 1.3
  */

public class SearchControls implements java.io.Serializable {
    /**
     * Search the named object.
     *<p>
     * The NamingEnumeration that results from search()
     * using OBJECT_SCOPE will contain one or zero element.
     * The enumeration contains one element if the named object satisfies
     * the search filter specified in search().
     * The element will have as its name the empty string because the names
     * of elements in the NamingEnumeration are relative to the 
     * target context--in this case, the target context is the named object.
     * It contains zero element if the named object does not satisfy
     * the search filter specified in search().
     * <p>
     * The value of this constant is <tt>0</tt>.
     */
    public final static int OBJECT_SCOPE = 0;

    /**
     * Search one level of the named context.
     *<p>
     * The NamingEnumeration that results from search()
     * using ONELEVEL_SCOPE contains elements with
     * objects in the named context that satisfy
     * the search filter specified in search().
     * The names of elements in the NamingEnumeration are atomic names
     * relative to the named context.
     * <p>
     * The value of this constant is <tt>1</tt>.
     */
    public final static int ONELEVEL_SCOPE = 1;
    /**
     * Search the entire subtree rooted at the named object.
     *<p>
     * If the named object is not a DirContext, search only the object.
     * If the named object is a DirContext, search the subtree
     * rooted at the named object, including the named object itself.
     *<p>
     * The search will not cross naming system boundaries.
     *<p>
     * The NamingEnumeration that results from search()
     * using SUBTREE_SCOPE contains elements of objects
     * from the subtree (including the named context)
     * that satisfy the search filter specified in search().
     * The names of elements in the NamingEnumeration are either
     * relative to the named context or is a URL string.
     * If the named context satisfies the search filter, it is
     * included in the enumeration with the empty string as 
     * its name.
     * <p>
     * The value of this constant is <tt>2</tt>.
     */
    public final static int SUBTREE_SCOPE = 2;

    /**
     * Contains the scope with which to apply the search. One of
     * <tt>ONELEVEL_SCOPE</tt>, <tt>OBJECT_SCOPE</tt>, or 
     * <tt>SUBTREE_SCOPE</tt>.
     * @serial
     */
    private int searchScope;

    /**
     * Contains the milliseconds to wait before returning
     * from search.
     * @serial
     */
    private int timeLimit;

    /**
     * Indicates whether JNDI links are dereferenced during
     * search.
     * @serial
     */
    private boolean derefLink;

    /**
     *  Indicates whether object is returned in <tt>SearchResult</tt>.
     * @serial
     */
    private boolean returnObj;

    /**
     * Contains the maximum number of SearchResults to return.
     * @serial
     */
    private long countLimit;

    /**
     *  Contains the list of attributes to be returned in
     * <tt>SearchResult</tt> for each matching entry of search. <tt>null</tt>
     * indicates that all attributes are to be returned.
     * @serial
     */
    private String[] attributesToReturn;

    /**
     * Constructs a search constraints using defaults.
     *<p>
     * The defaults are:
     * <ul>
     * <li>search one level
     * <li>no maximum return limit for search results
     * <li>no time limit for search
     * <li>return all attributes associated with objects that satisfy
     *   the search filter.
     * <li>do not return named object  (return only name and class)
     * <li>do not dereference links during search
     *</ul>
     */
    public SearchControls() {
	searchScope = ONELEVEL_SCOPE;
	timeLimit = 0; // no limit
	countLimit = 0; // no limit
	derefLink = false;
	returnObj = false;
	attributesToReturn = null; // return all
    }

    /**
     * Constructs a search constraints using arguments.
     * @param scope	The search scope.  One of:
     *			OBJECT_SCOPE, ONELEVEL_SCOPE, SUBTREE_SCOPE.
     * @param timelim	The number of milliseconds to wait before returning.
     *			If 0, wait indefinitely.
     * @param deref	If true, dereference links during search.
     * @param countlim	The maximum number of entries to return.  If 0, return
     *			all entries that satisfy filter.
     * @param retobj	If true, return the object bound to the name of the
     *			entry; if false, do not return object.
     * @param attrs	The identifiers of the attributes to return along with
     *			the entry.  If null, return all attributes. If empty
     *			return no attributes.
     */
    public SearchControls(int scope, 
			     long countlim, 
			     int timelim, 
			     String[] attrs,
			     boolean retobj, 
			     boolean deref) {
	searchScope = scope;
	timeLimit = timelim; // no limit
	derefLink = deref;
	returnObj = retobj;
	countLimit = countlim; // no limit
	attributesToReturn = attrs; // return all
    }

    /**
     * Retrieves the search scope of these SearchControls.
     *<p>
     * One of OBJECT_SCOPE, ONELEVEL_SCOPE, SUBTREE_SCOPE.
     *
     * @return The search scope of this SearchControls.
     * @see #setSearchScope
     */
    public int getSearchScope() {
	return searchScope;
    }

    /**
     * Retrieves the time limit of these SearchControls in milliseconds.
     *<p>
     * If the value is 0, this means to wait indefinitely.
     * @return The time limit of these SearchControls in milliseconds.
     * @see #setTimeLimit
     */
    public int getTimeLimit() {
	return timeLimit;
    }

    /**
     * Determines whether links will be dereferenced during the search.
     *
     * @return true if links will be dereferenced; false otherwise.
     * @see #setDerefLinkFlag
     */
    public boolean getDerefLinkFlag() {
	return derefLink;
    }

    /**
     * Determines whether objects will be returned as part of the result.
     * 
     * @return true if objects will be returned; false otherwise.
     * @see #setReturningObjFlag
     */
    public boolean getReturningObjFlag() {
	return returnObj;
    }

    /**
     * Retrieves the maximum number of entries that will be returned
     * as a result of the search.  
     *<p>
     * 0 indicates that all entries will be returned.
     * @return The maximum number of entries that will be returned.
     * @see #setCountLimit
     */
    public long getCountLimit() {
	return countLimit;
    }

    /**
     * Retrieves the attributes that will be returned as part of the search.
     *<p>
     * A value of null indicates that all attributes will be returned.
     * An empty array indicates that no attributes are to be returned.
     *
     * @return An array of attribute ids identifying the attributes that
     * will be returned. Can be null.
     * @see #setReturningAttributes
     */
    public String[] getReturningAttributes() {
	return attributesToReturn;
    }

    /**
     * Sets the search scope to one of:
     * OBJECT_SCOPE, ONELEVEL_SCOPE, SUBTREE_SCOPE.
     * @param scope	The search scope of this SearchControls.
     * @see #getSearchScope
     */
    public void setSearchScope(int scope) {
	searchScope = scope;
    }

    /**
     * Sets the time limit of these SearchControls in milliseconds.
     *<p>
     * If the value is 0, this means to wait indefinitely.
     * @param ms	The time limit of these SearchControls in milliseconds.
     * @see #getTimeLimit
     */
    public void setTimeLimit(int ms) {
	timeLimit = ms;
    }

    /**
     * Enables/disables link dereferencing during the search.
     *
     * @param on 	if true links will be dereferenced; if false, not followed.
     * @see #getDerefLinkFlag
     */
    public void setDerefLinkFlag(boolean on) {
	derefLink = on;
    }

    /**
     * Enables/disables returning objects returned as part of the result.
     *<p>
     * If disabled, only the name and class of the object is returned.
     * If enabled, the object will be returned.
     * 
     * @param on	if true, objects will be returned; if false, 
     * 			objects will not be returned.
     * @see #getReturningObjFlag
     */
    public void setReturningObjFlag(boolean on) {
	returnObj = on;
    }

    /**
     * Sets the maximum number of entries to be returned
     * as a result of the search.  
     *<p>
     * 0 indicates no limit:  all entries will be returned.
     * 
     * @param limit The maximum number of entries that will be returned.
     * @see #getCountLimit
     */
    public void setCountLimit(long limit) {
	countLimit = limit;
    }

    /**
     * Specifies the attributes that will be returned as part of the search.
     *<p>
     * null indicates that all attributes will be returned.
     * An empty array indicates no attributes are returned.
     *
     * @param attrs An array of attribute ids identifying the attributes that
     * 		    will be returned. Can be null.
     * @see #getReturningAttributes
     */
    public void setReturningAttributes(String[] attrs) {
	attributesToReturn = attrs;
    }

    /**
     * Use serialVersionUID from JNDI 1.1.1 for interoperability.
     */
    private static final long serialVersionUID = -2480540967773454797L;
}
