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

1	/*******************************************************************************
2	* Copyright (c) 2016, 2017 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	* IBM Corporation - initial API and implementation
12	*******************************************************************************/
13	package org.eclipse.jdt.core.dom;
14
15	import java.util.ArrayList;
16	import java.util.List;
17
18	/**
19	* Uses directive AST node type (added in JLS9 API).
20	* <pre>
21	* UsesDirective:
22	* <b>uses</b> Name <b>;</b>
23	* </pre>
24	*
25	* @since 3.14
26	*
27	* @noextend This class is not intended to be subclassed by clients.
28	* @noinstantiate This class is not intended to be instantiated by clients.
29	*/
30	@SuppressWarnings("rawtypes")
31	public class UsesDirective extends ModuleDirective {
32
33	/**
34	* The "name" structural property of this node type (child type: {@link Name}).
35	*/
36	public static final ChildPropertyDescriptor NAME_PROPERTY =
37	new ChildPropertyDescriptor(UsesDirective.class, "name", Name.class, MANDATORY, NO_CYCLE_RISK); //$NON-NLS-1$
38
39	/**
40	* A list of property descriptors (element type:
41	* {@link StructuralPropertyDescriptor}),
42	* or null if uninitialized.
43	*/
44	private static final List PROPERTY_DESCRIPTORS_9_0;
45
46	static {
47	List properyList = new ArrayList(2);
48	createPropertyList(UsesDirective.class, properyList);
49	addProperty(NAME_PROPERTY, properyList);
50	PROPERTY_DESCRIPTORS_9_0 = reapPropertyList(properyList);
51	}
52
53	/**
54	* Returns a list of structural property descriptors for this node type.
55	* Clients must not modify the result.
56	*
57	* @param apiLevel the API level; one of the
58	* <code>AST.JLS*</code> constants
59
60	* @return a list of property descriptors (element type:
61	* {@link StructuralPropertyDescriptor})
62	*/
63	public static List propertyDescriptors(int apiLevel) {
64	return PROPERTY_DESCRIPTORS_9_0;
65	}
66
67	/**
68	* The module name; lazily initialized; defaults to a unspecified,
69	* legal Java identifier.
70	*/
71	private Name name = null;
72
73	/**
74	* Creates a new AST node for an uses directive owned by the
75	* given AST. The uses directive initially is
76	* for an unspecified, but legal, Java type name.
77	* <p>
78	* N.B. This constructor is package-private; all subclasses must be
79	* declared in the same package; clients are unable to declare
80	* additional subclasses.
81	* </p>
82	*
83	* @param ast the AST that is to own this node
84	*/
85	UsesDirective(AST ast) {
86	super(ast);
87	}
88
89	@Override
90	final List internalStructuralPropertiesForType(int apiLevel) {
91	return propertyDescriptors(apiLevel);
92	}
93
94	@Override
95	final ASTNode internalGetSetChildProperty(ChildPropertyDescriptor property, boolean get, ASTNode child) {
96	if (property == NAME_PROPERTY) {
97	if (get) {
98	return getName();
99	} else {
100	setName((Name) child);
101	return null;
102	}
103	}
104
105	// allow default implementation to flag the error
106	return super.internalGetSetChildProperty(property, get, child);
107	}
108
109	@Override
110	final int getNodeType0() {
111	return USES_DIRECTIVE;
112	}
113
114	@Override
115	ASTNode clone0(AST target) {
116	UsesDirective result = new UsesDirective(target);
117	result.setSourceRange(getStartPosition(), getLength());
118	result.setName((Name) getName().clone(target));
119	return result;
120	}
121
122	@Override
123	final boolean subtreeMatch0(ASTMatcher matcher, Object other) {
124	// dispatch to correct overloaded match method
125	return matcher.match(this, other);
126	}
127
128	@Override
129	void accept0(ASTVisitor visitor) {
130	boolean visitChildren = visitor.visit(this);
131	if (visitChildren) {
132	acceptChild(visitor, getName());
133	}
134	visitor.endVisit(this);
135	}
136
137
138	/**
139	* Returns the name of the service in this directive.
140	*
141	* @return the name of the service
142	*/
143	public Name getName() {
144	if (this.name == null) {
145	// lazy init must be thread-safe for readers
146	synchronized (this) {
147	if (this.name == null) {
148	preLazyInit();
149	this.name = this.ast.newQualifiedName(
150	new SimpleName(this.ast), new SimpleName(this.ast));
151	postLazyInit(this.name, NAME_PROPERTY);
152	}
153	}
154	}
155	return this.name;
156	}
157
158	/**
159	* Sets the name of the service in this directive.
160	*
161	* @param name the new name of the service
162	* @exception IllegalArgumentException if:
163	* <ul>
164	* <li>the node belongs to a different AST</li>
165	* <li>the node already has a parent</li>
166	* </ul>
167	*/
168	public void setName(Name name) {
169	if (name == null) {
170	throw new IllegalArgumentException();
171	}
172	ASTNode oldChild = this.name;
173	preReplaceChild(oldChild, name, NAME_PROPERTY);
174	this.name = name;
175	postReplaceChild(oldChild, name, NAME_PROPERTY);
176	}
177
178	@Override
179	int memSize() {
180	return BASE_NODE_SIZE + 1 * 4;
181	}
182
183	@Override
184	int treeSize() {
185	return
186	memSize()
187	+ (this.name == null ? 0 : getName().treeSize());
188	}
189
190	}
191