/*

 * Copyright 2005-2008 Sun Microsystems, Inc.  All Rights Reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Sun designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Sun in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

package com.sun.source.util;

import java.lang.reflect.Method;

import javax.annotation.processing.ProcessingEnvironment;

import javax.lang.model.element.AnnotationMirror;

import javax.lang.model.element.AnnotationValue;

import javax.lang.model.element.Element;

import javax.lang.model.element.ExecutableElement;

import javax.lang.model.element.TypeElement;

import javax.lang.model.type.DeclaredType;

import javax.lang.model.type.ErrorType;

import javax.lang.model.type.TypeMirror;

import javax.tools.JavaCompiler.CompilationTask;

import com.sun.source.tree.ClassTree;

import com.sun.source.tree.CompilationUnitTree;

import com.sun.source.tree.MethodTree;

import com.sun.source.tree.Scope;

import com.sun.source.tree.Tree;

/**

 * Bridges JSR 199, JSR 269, and the Tree API.

 *

 * @author Peter von der Ahé

 */

public abstract class Trees {

    /**

     * Gets a Trees object for a given CompilationTask.

     * @throws IllegalArgumentException if the task does not support the Trees API.

     */

    public static Trees instance(CompilationTask task) {

        if (!task.getClass().getName().equals("com.sun.tools.javac.api.JavacTaskImpl"))

            throw new IllegalArgumentException();

        return getJavacTrees(CompilationTask.class, task);

    }

    /**

     * Gets a Trees object for a given CompilationTask.

     * @throws IllegalArgumentException if the env does not support the Trees API.

     */

    public static Trees instance(ProcessingEnvironment env) {

        if (!env.getClass().getName().equals("com.sun.tools.javac.processing.JavacProcessingEnvironment"))

            throw new IllegalArgumentException();

        return getJavacTrees(ProcessingEnvironment.class, env);

    }

    private static Trees getJavacTrees(Class<?> argType, Object arg) {

        try {

            ClassLoader cl = arg.getClass().getClassLoader();

            Class<?> c = Class.forName("com.sun.tools.javac.api.JavacTrees", false, cl);

            argType = Class.forName(argType.getName(), false, cl);

            return (Trees) m.invoke(null, new Object[] { arg });

        } catch (Throwable e) {

            throw new AssertionError(e);

        }

    }

    /**

     * Gets a utility object for obtaining source positions.

     */

    public abstract SourcePositions getSourcePositions();

    /**

     * Gets the Tree node for a given Element.

     * Returns null if the node can not be found.

     */

    public abstract Tree getTree(Element element);

    /**

     * Gets the ClassTree node for a given TypeElement.

     * Returns null if the node can not be found.

     */

    public abstract ClassTree getTree(TypeElement element);

    /**

     * Gets the MethodTree node for a given ExecutableElement.

     * Returns null if the node can not be found.

     */

    public abstract MethodTree getTree(ExecutableElement method);

    /**

     * Gets the Tree node for an AnnotationMirror on a given Element.

     * Returns null if the node can not be found.

     */

    public abstract Tree getTree(Element e, AnnotationMirror a);

    /**

     * Gets the Tree node for an AnnotationValue for an AnnotationMirror on a given Element.

     * Returns null if the node can not be found.

     */

    public abstract Tree getTree(Element e, AnnotationMirror a, AnnotationValue v);

    /**

     * Gets the path to tree node within the specified compilation unit.

     */

    public abstract TreePath getPath(CompilationUnitTree unit, Tree node);

    /**

     * Gets the TreePath node for a given Element.

     * Returns null if the node can not be found.

     */

    public abstract TreePath getPath(Element e);

    /**

     * Gets the TreePath node for an AnnotationMirror on a given Element.

     * Returns null if the node can not be found.

     */

    public abstract TreePath getPath(Element e, AnnotationMirror a);

    /**

     * Gets the TreePath node for an AnnotationValue for an AnnotationMirror on a given Element.

     * Returns null if the node can not be found.

     */

    public abstract TreePath getPath(Element e, AnnotationMirror a, AnnotationValue v);

    /**

     * Gets the Element for the Tree node identified by a given TreePath.

     * Returns null if the element is not available.

     * @throws IllegalArgumentException is the TreePath does not identify

     * a Tree node that might have an associated Element.

     */

    public abstract Element getElement(TreePath path);

    /**

     * Gets the TypeMirror for the Tree node identified by a given TreePath.

     * Returns null if the TypeMirror is not available.

     * @throws IllegalArgumentException is the TreePath does not identify

     * a Tree node that might have an associated TypeMirror.

     */

    public abstract TypeMirror getTypeMirror(TreePath path);

    /**

     * Gets the Scope for the Tree node identified by a given TreePath.

     * Returns null if the Scope is not available.

     */

    public abstract Scope getScope(TreePath path);

    /**

     * Checks whether a given type is accessible in a given scope.

     * @param scope the scope to be checked

     * @param type the type to be checked

     * @return true if {@code type} is accessible

     */

    public abstract boolean isAccessible(Scope scope, TypeElement type);

    /**

     * Checks whether the given element is accessible as a member of the given

     * type in a given scope.

     * @param scope the scope to be checked

     * @param member the member to be checked

     * @param type the type for which to check if the member is accessible

     * @return true if {@code member} is accessible in {@code type}

     */

    public abstract boolean isAccessible(Scope scope, Element member, DeclaredType type);

    /**

      * Gets the original type from the ErrorType object.

      * @param errorType The errorType for which we want to get the original type.

      * @returns javax.lang.model.type.TypeMirror corresponding to the original type, replaced by the ErrorType.

      */

    public abstract TypeMirror getOriginalType(ErrorType errorType);

}