1/*
2 * Copyright (c) 2005, 2014, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.  Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26package com.sun.source.util;
27
28import java.lang.reflect.Method;
29
30import javax.annotation.processing.ProcessingEnvironment;
31import javax.lang.model.element.AnnotationMirror;
32import javax.lang.model.element.AnnotationValue;
33import javax.lang.model.element.Element;
34import javax.lang.model.element.ExecutableElement;
35import javax.lang.model.element.TypeElement;
36import javax.lang.model.type.DeclaredType;
37import javax.lang.model.type.ErrorType;
38import javax.lang.model.type.TypeMirror;
39import javax.tools.Diagnostic;
40import javax.tools.JavaCompiler.CompilationTask;
41
42import com.sun.source.tree.CatchTree;
43import com.sun.source.tree.ClassTree;
44import com.sun.source.tree.CompilationUnitTree;
45import com.sun.source.tree.MethodTree;
46import com.sun.source.tree.Scope;
47import com.sun.source.tree.Tree;
48
49/**
50 * Bridges JSR 199, JSR 269, and the Tree API.
51 *
52 * @author Peter von der Ahé
53 */
54public abstract class Trees {
55    /**
56     * Returns a Trees object for a given CompilationTask.
57     * @param task the compilation task for which to get the Trees object
58     * @throws IllegalArgumentException if the task does not support the Trees API.
59     * @return the Trees object
60     */
61    public static Trees instance(CompilationTask task) {
62        String taskClassName = task.getClass().getName();
63        if (!taskClassName.equals("com.sun.tools.javac.api.JavacTaskImpl")
64                && !taskClassName.equals("com.sun.tools.javac.api.BasicJavacTask"))
65            throw new IllegalArgumentException();
66        return getJavacTrees(CompilationTask.class, task);
67    }
68
69    /**
70     * Returns a Trees object for a given ProcessingEnvironment.
71     * @param env the processing environment for which to get the Trees object
72     * @throws IllegalArgumentException if the env does not support the Trees API.
73     * @return the Trees object
74     */
75    public static Trees instance(ProcessingEnvironment env) {
76        if (!env.getClass().getName().equals("com.sun.tools.javac.processing.JavacProcessingEnvironment"))
77            throw new IllegalArgumentException();
78        return getJavacTrees(ProcessingEnvironment.class, env);
79    }
80
81    static Trees getJavacTrees(Class<?> argType, Object arg) {
82        try {
83            ClassLoader cl = arg.getClass().getClassLoader();
84            Class<?> c = Class.forName("com.sun.tools.javac.api.JavacTrees", false, cl);
85            argType = Class.forName(argType.getName(), false, cl);
86            Method m = c.getMethod("instance", argType);
87            return (Trees) m.invoke(null, arg);
88        } catch (ReflectiveOperationException e) {
89            throw new AssertionError(e);
90        }
91    }
92
93    /**
94     * Returns a utility object for obtaining source positions.
95     * @return the utility object for obtaining source positions
96     */
97    public abstract SourcePositions getSourcePositions();
98
99    /**
100     * Returns the Tree node for a given Element.
101     * Returns {@code null} if the node can not be found.
102     * @param element the element
103     * @return the tree node
104     */
105    public abstract Tree getTree(Element element);
106
107    /**
108     * Returns the ClassTree node for a given TypeElement.
109     * Returns {@code null} if the node can not be found.
110     * @param element the element
111     * @return the class tree node
112     */
113    public abstract ClassTree getTree(TypeElement element);
114
115    /**
116     * Returns the MethodTree node for a given ExecutableElement.
117     * Returns {@code null} if the node can not be found.
118     * @param method the executable element
119     * @return the method tree node
120     */
121    public abstract MethodTree getTree(ExecutableElement method);
122
123    /**
124     * Returns the Tree node for an AnnotationMirror on a given Element.
125     * Returns {@code null} if the node can not be found.
126     * @param e the element
127     * @param a the annotation mirror
128     * @return the tree node
129     */
130    public abstract Tree getTree(Element e, AnnotationMirror a);
131
132    /**
133     * Returns the Tree node for an AnnotationValue for an AnnotationMirror on a given Element.
134     * Returns {@code null} if the node can not be found.
135     * @param e the element
136     * @param a the annotation mirror
137     * @param v the annotation value
138     * @return the tree node
139     */
140    public abstract Tree getTree(Element e, AnnotationMirror a, AnnotationValue v);
141
142    /**
143     * Returns the path to tree node within the specified compilation unit.
144     * @param unit the compilation unit
145     * @param node the tree node
146     * @return the tree path
147     */
148    public abstract TreePath getPath(CompilationUnitTree unit, Tree node);
149
150    /**
151     * Returns the TreePath node for a given Element.
152     * Returns {@code null} if the node can not be found.
153     * @param e the element
154     * @return the tree path
155     */
156    public abstract TreePath getPath(Element e);
157
158    /**
159     * Returns the TreePath node for an AnnotationMirror on a given Element.
160     * Returns {@code null} if the node can not be found.
161     * @param e the element
162     * @param a the annotation mirror
163     * @return the tree path
164     */
165    public abstract TreePath getPath(Element e, AnnotationMirror a);
166
167    /**
168     * Returns the TreePath node for an AnnotationValue for an AnnotationMirror on a given Element.
169     * Returns {@code null} if the node can not be found.
170     * @param e the element
171     * @param a the annotation mirror
172     * @param v the annotation value
173     * @return the tree path
174     */
175    public abstract TreePath getPath(Element e, AnnotationMirror a, AnnotationValue v);
176
177    /**
178     * Returns the Element for the Tree node identified by a given TreePath.
179     * Returns {@code null} if the element is not available.
180     * @param path the tree path
181     * @return the element
182     * @throws IllegalArgumentException is the TreePath does not identify
183     * a Tree node that might have an associated Element.
184     */
185    public abstract Element getElement(TreePath path);
186
187    /**
188     * Returns the TypeMirror for the Tree node identified by a given TreePath.
189     * Returns {@code null} if the TypeMirror is not available.
190     * @param path the tree path
191     * @return the type mirror
192     * @throws IllegalArgumentException is the TreePath does not identify
193     * a Tree node that might have an associated TypeMirror.
194     */
195    public abstract TypeMirror getTypeMirror(TreePath path);
196
197    /**
198     * Returns the Scope for the Tree node identified by a given TreePath.
199     * Returns {@code null} if the Scope is not available.
200     * @param path the tree path
201     * @return the scope
202     */
203    public abstract Scope getScope(TreePath path);
204
205    /**
206     * Returns the doc comment, if any, for the Tree node identified by a given TreePath.
207     * Returns {@code null} if no doc comment was found.
208     * @see DocTrees#getDocCommentTree(TreePath)
209     * @param path the tree path
210     * @return the doc comment
211     */
212    public abstract String getDocComment(TreePath path);
213
214    /**
215     * Checks whether a given type is accessible in a given scope.
216     * @param scope the scope to be checked
217     * @param type the type to be checked
218     * @return true if {@code type} is accessible
219     */
220    public abstract boolean isAccessible(Scope scope, TypeElement type);
221
222    /**
223     * Checks whether the given element is accessible as a member of the given
224     * type in a given scope.
225     * @param scope the scope to be checked
226     * @param member the member to be checked
227     * @param type the type for which to check if the member is accessible
228     * @return true if {@code member} is accessible in {@code type}
229     */
230    public abstract boolean isAccessible(Scope scope, Element member, DeclaredType type);
231
232    /**
233      * Returns the original type from the ErrorType object.
234      * @param errorType The errorType for which we want to get the original type.
235      * @return javax.lang.model.type.TypeMirror corresponding to the original type, replaced by the ErrorType.
236      */
237    public abstract TypeMirror getOriginalType(ErrorType errorType);
238
239    /**
240     * Prints a message of the specified kind at the location of the
241     * tree within the provided compilation unit
242     *
243     * @param kind the kind of message
244     * @param msg  the message, or an empty string if none
245     * @param t    the tree to use as a position hint
246     * @param root the compilation unit that contains tree
247     */
248    public abstract void printMessage(Diagnostic.Kind kind, CharSequence msg,
249            com.sun.source.tree.Tree t,
250            com.sun.source.tree.CompilationUnitTree root);
251
252    /**
253     * Returns the lub of an exception parameter declared in a catch clause.
254     * @param tree the tree for the catch clause
255     * @return The lub of the exception parameter
256     */
257    public abstract TypeMirror getLub(CatchTree tree);
258}
259