1 /*

     2 * Copyright (c) 2007 Nokia Corporation and/or its subsidiary(-ies). 

     3 * All rights reserved.

     4 * This component and the accompanying materials are made available

     5 * under the terms of "Eclipse Public License v1.0"

     6 * which accompanies this distribution, and is available

     7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     8 *

     9 * Initial Contributors:

    10 * Nokia Corporation - initial contribution.

    11 *

    12 * Contributors:

    13 *

    14 * Description:

    15 *

    16 * Represents a location in source

    17 *

    18 */

    19 package com.nokia.tracecompiler.source;

    20 

    21 import java.util.ArrayList;

    22 import java.util.Collections;

    23 import java.util.Iterator;

    24 import java.util.List;

    25 

    26 /**

    27  * Represents a location in source

    28  * 

    29  */

    30 public class SourceLocation extends SourceLocationBase {

    31 

    32 	/**

    33 	 * Location listeners

    34 	 */

    35 	private ArrayList<SourceLocationListener> locationListeners;

    36 

    37 	/**

    38 	 * Temporary array for callback purposes. Prevents concurrent modifications

    39 	 * if listeners are removed during a callback

    40 	 */

    41 	private ArrayList<SourceLocationListener> tempListeners;

    42 

    43 	/**

    44 	 * Reference count

    45 	 */

    46 	private int refCount = 0;

    47 

    48 	/**

    49 	 * Listener change flag

    50 	 */

    51 	private boolean listenersChanged = true;

    52 

    53 	/**

    54 	 * Constructor

    55 	 * 

    56 	 * @param parser

    57 	 *            the parser owning this location

    58 	 * @param offset

    59 	 *            offset of location

    60 	 * @param length

    61 	 *            length of location

    62 	 */

    63 	public SourceLocation(SourceParser parser, int offset, int length) {

    64 		super(parser, offset, length);

    65 		parser.addLocation(this);

    66 		refCount = 1;

    67 	}

    68 

    69 	/**

    70 	 * Gets the name of the class which owns this location

    71 	 * 

    72 	 * @return the class name

    73 	 */

    74 	public String getClassName() {

    75 		String retval = null;

    76 		if (getParser() != null) {

    77 			SourceContext context = getParser().getContext(getOffset());

    78 			if (context != null) {

    79 				retval = context.getClassName();

    80 			}

    81 		}

    82 		return retval;

    83 	}

    84 

    85 	/**

    86 	 * Gets the name of function which owns this location

    87 	 * 

    88 	 * @return the function name

    89 	 */

    90 	public String getFunctionName() {

    91 		String retval = null;

    92 		if (getParser() != null) {

    93 			SourceContext context = getParser().getContext(getOffset());

    94 			if (context != null) {

    95 				retval = context.getFunctionName();

    96 			}

    97 		}

    98 		return retval;

    99 	}

   100 

   101 	/**

   102 	 * Adds a location listener to this location

   103 	 * 

   104 	 * @param listener

   105 	 *            the location listener

   106 	 */

   107 	public void addLocationListener(SourceLocationListener listener) {

   108 		if (locationListeners == null) {

   109 			locationListeners = new ArrayList<SourceLocationListener>();

   110 		}

   111 		locationListeners.add(listener);

   112 		listenersChanged = true;

   113 	}

   114 

   115 	/**

   116 	 * Removes a location listener from this location

   117 	 * 

   118 	 * @param listener

   119 	 *            the location listener

   120 	 */

   121 	public void removeLocationListener(SourceLocationListener listener) {

   122 		if (locationListeners != null) {

   123 			if (locationListeners.remove(listener)) {

   124 				listenersChanged = true;

   125 			}

   126 		}

   127 	}

   128 

   129 	/**

   130 	 * Gets the listener interfaces

   131 	 * 

   132 	 * @return the listeners

   133 	 */

   134 	protected Iterator<SourceLocationListener> getListeners() {

   135 		List<SourceLocationListener> list;

   136 		if (locationListeners != null) {

   137 			if (listenersChanged) {

   138 				listenersChanged = false;

   139 				if (tempListeners == null) {

   140 					tempListeners = new ArrayList<SourceLocationListener>();

   141 				}

   142 				tempListeners.clear();

   143 				tempListeners.addAll(locationListeners);

   144 			}

   145 			list = tempListeners;

   146 		} else {

   147 			list = Collections.emptyList();

   148 		}

   149 		return list.iterator();

   150 	}

   151 

   152 	/**

   153 	 * Increases the reference count of this location.

   154 	 * 

   155 	 * @see #dereference()

   156 	 */

   157 	public void reference() {

   158 		refCount++;

   159 	}

   160 

   161 	/**

   162 	 * Decrements the reference count of this location. When reference count is

   163 	 * 0, this is removed from source. Note that a location can also be removed

   164 	 * from source even if it has outstanding references left. In that case it

   165 	 * can no longer be selected.

   166 	 */

   167 	public void dereference() {

   168 		if (--refCount <= 0) {

   169 			removeFromSource();

   170 		}

   171 	}

   172 

   173 	/**

   174 	 * Removes this location from the source

   175 	 */

   176 	private void removeFromSource() {

   177 		delete();

   178 		if (getParser() != null) {

   179 			getParser().removeLocation(this);

   180 			resetParser();

   181 		}

   182 	}

   183 

   184 }