001    /*
002     * Copyright 2005-2008 Sun Microsystems, Inc.  All Rights Reserved.
003     * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
004     *
005     * This code is free software; you can redistribute it and/or modify it
006     * under the terms of the GNU General Public License version 2 only, as
007     * published by the Free Software Foundation.  Sun designates this
008     * particular file as subject to the "Classpath" exception as provided
009     * by Sun in the LICENSE file that accompanied this code.
010     *
011     * This code is distributed in the hope that it will be useful, but WITHOUT
012     * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
013     * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
014     * version 2 for more details (a copy is included in the LICENSE file that
015     * accompanied this code).
016     *
017     * You should have received a copy of the GNU General Public License version
018     * 2 along with this work; if not, write to the Free Software Foundation,
019     * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
020     *
021     * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
022     * CA 95054 USA or visit www.sun.com if you need additional information or
023     * have any questions.
024     */
025    
026    package com.sun.source.util;
027    
028    import java.lang.reflect.Method;
029    import javax.annotation.processing.ProcessingEnvironment;
030    import javax.lang.model.element.AnnotationMirror;
031    import javax.lang.model.element.AnnotationValue;
032    import javax.lang.model.element.Element;
033    import javax.lang.model.element.ExecutableElement;
034    import javax.lang.model.element.TypeElement;
035    import javax.lang.model.type.DeclaredType;
036    import javax.lang.model.type.ErrorType;
037    import javax.lang.model.type.TypeMirror;
038    import javax.tools.JavaCompiler.CompilationTask;
039    
040    import com.sun.source.tree.ClassTree;
041    import com.sun.source.tree.CompilationUnitTree;
042    import com.sun.source.tree.MethodTree;
043    import com.sun.source.tree.Scope;
044    import com.sun.source.tree.Tree;
045    
046    /**
047     * Bridges JSR 199, JSR 269, and the Tree API.
048     *
049     * @author Peter von der Ahé
050     */
051    public abstract class Trees {
052        /**
053         * Gets a Trees object for a given CompilationTask.
054         * @throws IllegalArgumentException if the task does not support the Trees API.
055         */
056        public static Trees instance(CompilationTask task) {
057            if (!task.getClass().getName().equals("com.sun.tools.javac.api.JavacTaskImpl"))
058                throw new IllegalArgumentException();
059            return getJavacTrees(CompilationTask.class, task);
060        }
061    
062        /**
063         * Gets a Trees object for a given CompilationTask.
064         * @throws IllegalArgumentException if the env does not support the Trees API.
065         */
066        public static Trees instance(ProcessingEnvironment env) {
067            if (!env.getClass().getName().equals("com.sun.tools.javac.processing.JavacProcessingEnvironment"))
068                throw new IllegalArgumentException();
069            return getJavacTrees(ProcessingEnvironment.class, env);
070        }
071    
072        private static Trees getJavacTrees(Class<?> argType, Object arg) {
073            try {
074                ClassLoader cl = arg.getClass().getClassLoader();
075                Class<?> c = Class.forName("com.sun.tools.javac.api.JavacTrees", false, cl);
076                argType = Class.forName(argType.getName(), false, cl);
077                Method m = c.getMethod("instance", new Class<?>[] { argType });
078                return (Trees) m.invoke(null, new Object[] { arg });
079            } catch (Throwable e) {
080                throw new AssertionError(e);
081            }
082        }
083    
084        /**
085         * Gets a utility object for obtaining source positions.
086         */
087        public abstract SourcePositions getSourcePositions();
088    
089        /**
090         * Gets the Tree node for a given Element.
091         * Returns null if the node can not be found.
092         */
093        public abstract Tree getTree(Element element);
094    
095        /**
096         * Gets the ClassTree node for a given TypeElement.
097         * Returns null if the node can not be found.
098         */
099        public abstract ClassTree getTree(TypeElement element);
100    
101        /**
102         * Gets the MethodTree node for a given ExecutableElement.
103         * Returns null if the node can not be found.
104         */
105        public abstract MethodTree getTree(ExecutableElement method);
106    
107        /**
108         * Gets the Tree node for an AnnotationMirror on a given Element.
109         * Returns null if the node can not be found.
110         */
111        public abstract Tree getTree(Element e, AnnotationMirror a);
112    
113        /**
114         * Gets the Tree node for an AnnotationValue for an AnnotationMirror on a given Element.
115         * Returns null if the node can not be found.
116         */
117        public abstract Tree getTree(Element e, AnnotationMirror a, AnnotationValue v);
118    
119        /**
120         * Gets the path to tree node within the specified compilation unit.
121         */
122        public abstract TreePath getPath(CompilationUnitTree unit, Tree node);
123    
124        /**
125         * Gets the TreePath node for a given Element.
126         * Returns null if the node can not be found.
127         */
128        public abstract TreePath getPath(Element e);
129    
130        /**
131         * Gets the TreePath node for an AnnotationMirror on a given Element.
132         * Returns null if the node can not be found.
133         */
134        public abstract TreePath getPath(Element e, AnnotationMirror a);
135    
136        /**
137         * Gets the TreePath node for an AnnotationValue for an AnnotationMirror on a given Element.
138         * Returns null if the node can not be found.
139         */
140        public abstract TreePath getPath(Element e, AnnotationMirror a, AnnotationValue v);
141    
142        /**
143         * Gets the Element for the Tree node identified by a given TreePath.
144         * Returns null if the element is not available.
145         * @throws IllegalArgumentException is the TreePath does not identify
146         * a Tree node that might have an associated Element.
147         */
148        public abstract Element getElement(TreePath path);
149    
150        /**
151         * Gets the TypeMirror for the Tree node identified by a given TreePath.
152         * Returns null if the TypeMirror is not available.
153         * @throws IllegalArgumentException is the TreePath does not identify
154         * a Tree node that might have an associated TypeMirror.
155         */
156        public abstract TypeMirror getTypeMirror(TreePath path);
157    
158        /**
159         * Gets the Scope for the Tree node identified by a given TreePath.
160         * Returns null if the Scope is not available.
161         */
162        public abstract Scope getScope(TreePath path);
163    
164        /**
165         * Checks whether a given type is accessible in a given scope.
166         * @param scope the scope to be checked
167         * @param type the type to be checked
168         * @return true if {@code type} is accessible
169         */
170        public abstract boolean isAccessible(Scope scope, TypeElement type);
171    
172        /**
173         * Checks whether the given element is accessible as a member of the given
174         * type in a given scope.
175         * @param scope the scope to be checked
176         * @param member the member to be checked
177         * @param type the type for which to check if the member is accessible
178         * @return true if {@code member} is accessible in {@code type}
179         */
180        public abstract boolean isAccessible(Scope scope, Element member, DeclaredType type);
181    
182        /**
183          * Gets the original type from the ErrorType object.
184          * @param errorType The errorType for which we want to get the original type.
185          * @returns javax.lang.model.type.TypeMirror corresponding to the original type, replaced by the ErrorType.
186          */
187        public abstract TypeMirror getOriginalType(ErrorType errorType);
188    }