SPart


1   /*******************************************************************************
2    * Copyright (c) 2005, 2006 IBM Corporation and others.
3    * All rights reserved. This program and the accompanying materials
4    * are made available under the terms of the Eclipse Public License v1.0
5    * which accompanies this distribution, and is available at
6    * http://www.eclipse.org/legal/epl-v10.html
7    *
8    * Contributors:
9    *     IBM Corporation - initial API and implementation
10   *******************************************************************************/
11  
12  package org.eclipse.ui.internal.menus;
13  
14  /**
15   * <p>
16   * A location element that is used to select a specific part within the
17   * application. In the Eclipse workbench, this correspond with the concept of a
18   * part. Within JFace, this can refer to any similar ideas or can just be
19   * ignored.
20   * </p>
21   * <p>
22   * Clients may instantiate this class, but must not extend.
23   * </p>
24   * <p>
25   * <strong>PROVISIONAL</strong>. This class or interface has been added as
26   * part of a work in progress. There is a guarantee neither that this API will
27   * work nor that it will remain the same. Please do not use this API without
28   * consulting with the Platform/UI team.
29   * </p>
30   * <p>
31   * This class will eventually exist in <code>org.eclipse.jface.menus</code>.
32   * </p>
33   * 
34   * @since 3.2
35   * 
36   */
37  public final class SPart implements LocationElement {
38  
39      /**
40       * The constant used to indicate that the <code>part</code> is a class.
41       */
42      public static final int TYPE_CLASS = 0;
43  
44      /**
45       * The constant used to indicate that the <code>part</code> is an
46       * identifier.
47       */
48      public static final int TYPE_ID = 1;
49  
50      /**
51       * The location within the part to place the menu element.
52       */
53      private final LeafLocationElement location;
54  
55      /**
56       * The identifier of the part to which this instance refers, or the class
57       * (i.e., class, super class, interface or super interface) of the part.
58       * This value must not be <code>null</code>.
59       */
60      private final String   part;
61  
62      /**
63       * The type of information carried in <code>part</code>.
64       */
65      private final int type;
66  
67      /**
68       * Constructs a new instance of <code>SPart</code>.
69       * 
70       * @param part
71       *            The part to which this refers. Either its identifier or its
72       *            class. Must not be <code>null</code>.
73       * @param type
74       *            The type of data carried in <code>part</code>.
75       * @param location
76       *            The location within this part that the menu element should be
77       *            placed. Must not be <code>null</code>.
78       */
79      public SPart(final String   part, final int type,
80              final LeafLocationElement location) {
81          if (part == null) {
82              throw new NullPointerException  ("A part needs a class or id"); //$NON-NLS-1$
83          }
84          if ((type < TYPE_CLASS) || (type > TYPE_ID)) {
85              throw new IllegalArgumentException  (
86                      "The part must be either a class or an identifier"); //$NON-NLS-1$
87          }
88          if (location == null) {
89              throw new NullPointerException  (
90                      "A part needs a location for the menu element to appear"); //$NON-NLS-1$
91          }
92  
93          this.part = part;
94          this.type = type;
95          this.location = location;
96      }
97  
98      public final LocationElement createChild(final String   id) {
99          final LeafLocationElement childPath = (LeafLocationElement) getLocation()
100                 .createChild(id);
101         return new SPart(getPart(), getType(), childPath);
102     }
103 
104     /**
105      * Returns the location within this part that the menu element should be
106      * placed. Must not be <code>null</code>.
107      * 
108      * @return The location in which the menu element should be placed; never
109      *         <code>null</code>.
110      */
111     public final LeafLocationElement getLocation() {
112         return location;
113     }
114 
115     /**
116      * Returns either the class name to which this part refers or the identifier
117      * of the part. The type is indicated by a call to {@link SPart#getType()}
118      * 
119      * @return The class name or identifier; never <code>null</code>.
120      */
121     public final String   getPart() {
122         return part;
123     }
124 
125     /**
126      * Returns the type of this part. This indicates whether this part refers to
127      * an identifier or to a class.
128      * 
129      * @return Either <code>TYPE_CLASS</code> or <code>TYPE_ID</code>.
130      */
131     public final int getType() {
132         return type;
133     }
134 
135     public final String   toString() {
136         final StringBuffer   buffer = new StringBuffer  ();
137         buffer.append("SPart("); //$NON-NLS-1$
138         switch (type) {
139         case TYPE_CLASS:
140             buffer.append("class"); //$NON-NLS-1$
141             break;
142         case TYPE_ID:
143             buffer.append("id"); //$NON-NLS-1$
144             break;
145         default:
146             buffer.append("unknown"); //$NON-NLS-1$
147         }
148         buffer.append(',');
149         buffer.append(part);
150         buffer.append(',');
151         buffer.append(location);
152         buffer.append(')');
153         return buffer.toString();
154     }
155 }
156
A to Z: JavaDoc & Examples Daily Java News & Articles Open Source Projects Open Source Codes Free Computer Books Remove Frame
Popular Tags