eclipse_jdt/src/org/eclipse/jdt/core/dom/EnhancedForStatement.java

1	/*******************************************************************************
2	* Copyright (c) 2000, 2013 IBM Corporation and others.
3	*
4	* This program and the accompanying materials
5	* are made available under the terms of the Eclipse Public License 2.0
6	* which accompanies this distribution, and is available at
7	* https://www.eclipse.org/legal/epl-2.0/
8	*
9	* SPDX-License-Identifier: EPL-2.0
10	*
11	* Contributors:
12	* IBM Corporation - initial API and implementation
13	*******************************************************************************/
14
15	package org.eclipse.jdt.core.dom;
16
17	import java.util.ArrayList;
18	import java.util.List;
19
20	/**
21	* Enhanced For statement AST node type (added in JLS3 API).
22	*
23	* <pre>
24	* EnhancedForStatement:
25	* <b>for</b> <b>(</b> FormalParameter <b>:</b> Expression <b>)</b>
26	* Statement
27	* </pre>
28	*
29	* <p>The FormalParameter is represented by a {@link SingleVariableDeclaration}
30	* (without an initializer).</p>
31	*
32	* @since 3.1
33	* @noinstantiate This class is not intended to be instantiated by clients.
34	*/
35	@SuppressWarnings("rawtypes")
36	public class EnhancedForStatement extends Statement {
37
38	/**
39	* The "parameter" structural property of this node type (child type: {@link SingleVariableDeclaration}).
40	*/
41	public static final ChildPropertyDescriptor PARAMETER_PROPERTY =
42	new ChildPropertyDescriptor(EnhancedForStatement.class, "parameter", SingleVariableDeclaration.class, MANDATORY, CYCLE_RISK); //$NON-NLS-1$
43
44	/**
45	* The "expression" structural property of this node type (child type: {@link Expression}).
46	*/
47	public static final ChildPropertyDescriptor EXPRESSION_PROPERTY =
48	new ChildPropertyDescriptor(EnhancedForStatement.class, "expression", Expression.class, MANDATORY, CYCLE_RISK); //$NON-NLS-1$
49
50	/**
51	* The "body" structural property of this node type (child type: {@link Statement}).
52	*/
53	public static final ChildPropertyDescriptor BODY_PROPERTY =
54	new ChildPropertyDescriptor(EnhancedForStatement.class, "body", Statement.class, MANDATORY, CYCLE_RISK); //$NON-NLS-1$
55
56	/**
57	* A list of property descriptors (element type:
58	* {@link StructuralPropertyDescriptor}),
59	* or null if uninitialized.
60	*/
61	private static final List PROPERTY_DESCRIPTORS;
62
63	static {
64	List properyList = new ArrayList(4);
65	createPropertyList(EnhancedForStatement.class, properyList);
66	addProperty(PARAMETER_PROPERTY, properyList);
67	addProperty(EXPRESSION_PROPERTY, properyList);
68	addProperty(BODY_PROPERTY, properyList);
69	PROPERTY_DESCRIPTORS = reapPropertyList(properyList);
70	}
71
72	/**
73	* Returns a list of structural property descriptors for this node type.
74	* Clients must not modify the result.
75	*
76	* @param apiLevel the API level; one of the
77	* <code>AST.JLS*</code> constants
78
79	* @return a list of property descriptors (element type:
80	* {@link StructuralPropertyDescriptor})
81	*/
82	public static List propertyDescriptors(int apiLevel) {
83	return PROPERTY_DESCRIPTORS;
84	}
85
86	/**
87	* The parameter; lazily initialized; defaults to a unspecified,
88	* legal node.
89	*/
90	private SingleVariableDeclaration parameter = null;
91
92	/**
93	* The expression; lazily initialized; defaults to a unspecified, but legal,
94	* expression.
95	*/
96	private Expression expression = null;
97
98	/**
99	* The body statement; lazily initialized; defaults to an empty block
100	* statement.
101	*/
102	private Statement body = null;
103
104	/**
105	* Creates a new AST node for an enchanced for statement owned by the
106	* given AST. By default, the parameter and expression are unspecified
107	* but legal subtrees, and the body is an empty block.
108	*
109	* @param ast the AST that is to own this node
110	*/
111	EnhancedForStatement(AST ast) {
112	super(ast);
113	unsupportedIn2();
114	}
115
116	@Override
117	final List internalStructuralPropertiesForType(int apiLevel) {
118	return propertyDescriptors(apiLevel);
119	}
120
121	@Override
122	final ASTNode internalGetSetChildProperty(ChildPropertyDescriptor property, boolean get, ASTNode child) {
123	if (property == PARAMETER_PROPERTY) {
124	if (get) {
125	return getParameter();
126	} else {
127	setParameter((SingleVariableDeclaration) child);
128	return null;
129	}
130	}
131	if (property == EXPRESSION_PROPERTY) {
132	if (get) {
133	return getExpression();
134	} else {
135	setExpression((Expression) child);
136	return null;
137	}
138	}
139	if (property == BODY_PROPERTY) {
140	if (get) {
141	return getBody();
142	} else {
143	setBody((Statement) child);
144	return null;
145	}
146	}
147	// allow default implementation to flag the error
148	return super.internalGetSetChildProperty(property, get, child);
149	}
150
151	@Override
152	final int getNodeType0() {
153	return ENHANCED_FOR_STATEMENT;
154	}
155
156	@Override
157	ASTNode clone0(AST target) {
158	EnhancedForStatement result = new EnhancedForStatement(target);
159	result.setSourceRange(getStartPosition(), getLength());
160	result.copyLeadingComment(this);
161	result.setParameter((SingleVariableDeclaration) getParameter().clone(target));
162	result.setExpression((Expression) getExpression().clone(target));
163	result.setBody(
164	(Statement) ASTNode.copySubtree(target, getBody()));
165	return result;
166	}
167
168	@Override
169	final boolean subtreeMatch0(ASTMatcher matcher, Object other) {
170	// dispatch to correct overloaded match method
171	return matcher.match(this, other);
172	}
173
174	@Override
175	void accept0(ASTVisitor visitor) {
176	boolean visitChildren = visitor.visit(this);
177	if (visitChildren) {
178	// visit children in normal left to right reading order
179	acceptChild(visitor, getParameter());
180	acceptChild(visitor, getExpression());
181	acceptChild(visitor, getBody());
182	}
183	visitor.endVisit(this);
184	}
185
186	/**
187	* Returns the formal parameter in this enhanced for statement.
188	*
189	* @return the parameter
190	*/
191	public SingleVariableDeclaration getParameter() {
192	if (this.parameter == null) {
193	// lazy init must be thread-safe for readers
194	synchronized (this) {
195	if (this.parameter == null) {
196	preLazyInit();
197	this.parameter = this.ast.newSingleVariableDeclaration();
198	postLazyInit(this.parameter, PARAMETER_PROPERTY);
199	}
200	}
201	}
202	return this.parameter;
203	}
204
205	/**
206	* Sets the formal parameter in this enhanced for statement.
207	*
208	* @param parameter the new parameter
209	* @exception IllegalArgumentException if:
210	* <ul>
211	* <li>the node belongs to a different AST</li>
212	* <li>the node already has a parent</li>
213	* </ul>
214	*/
215	public void setParameter(SingleVariableDeclaration parameter) {
216	if (parameter == null) {
217	throw new IllegalArgumentException();
218	}
219	ASTNode oldChild = this.parameter;
220	preReplaceChild(oldChild, parameter, PARAMETER_PROPERTY);
221	this.parameter = parameter;
222	postReplaceChild(oldChild, parameter, PARAMETER_PROPERTY);
223	}
224
225	/**
226	* Returns the expression of this enhanced for statement.
227	*
228	* @return the expression node
229	*/
230	public Expression getExpression() {
231	if (this.expression == null) {
232	// lazy init must be thread-safe for readers
233	synchronized (this) {
234	if (this.expression == null) {
235	preLazyInit();
236	this.expression = new SimpleName(this.ast);
237	postLazyInit(this.expression, EXPRESSION_PROPERTY);
238	}
239	}
240	}
241	return this.expression;
242	}
243
244	/**
245	* Sets the expression of this enhanced for statement.
246	*
247	* @param expression the new expression node
248	* @exception IllegalArgumentException if:
249	* <ul>
250	* <li>the node belongs to a different AST</li>
251	* <li>the node already has a parent</li>
252	* <li>a cycle in would be created</li>
253	* </ul>
254	*/
255	public void setExpression(Expression expression) {
256	if (expression == null) {
257	throw new IllegalArgumentException();
258	}
259	ASTNode oldChild = this.expression;
260	preReplaceChild(oldChild, expression, EXPRESSION_PROPERTY);
261	this.expression = expression;
262	postReplaceChild(oldChild, expression, EXPRESSION_PROPERTY);
263	}
264
265	/**
266	* Returns the body of this enchanced for statement.
267	*
268	* @return the body statement node
269	*/
270	public Statement getBody() {
271	if (this.body == null) {
272	// lazy init must be thread-safe for readers
273	synchronized (this) {
274	if (this.body == null) {
275	preLazyInit();
276	this.body = new Block(this.ast);
277	postLazyInit(this.body, BODY_PROPERTY);
278	}
279	}
280	}
281	return this.body;
282	}
283
284	/**
285	* Sets the body of this enhanced for statement.
286	*
287	* @param statement the body statement node
288	* @exception IllegalArgumentException if:
289	* <ul>
290	* <li>the node belongs to a different AST</li>
291	* <li>the node already has a parent</li>
292	* <li>a cycle in would be created</li>
293	* </ul>
294	*/
295	public void setBody(Statement statement) {
296	if (statement == null) {
297	throw new IllegalArgumentException();
298	}
299	ASTNode oldChild = this.body;
300	preReplaceChild(oldChild, statement, BODY_PROPERTY);
301	this.body = statement;
302	postReplaceChild(oldChild, statement, BODY_PROPERTY);
303	}
304
305	@Override
306	int memSize() {
307	return super.memSize() + 3 * 4;
308	}
309
310	@Override
311	int treeSize() {
312	return
313	memSize()
314	+ (this.parameter == null ? 0 : getParameter().treeSize())
315	+ (this.expression == null ? 0 : getExpression().treeSize())
316	+ (this.body == null ? 0 : getBody().treeSize());
317	}
318	}
319