/*

 * Copyright (c) 2006, 2014, Oracle and/or its affiliates. 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.  Oracle designates this

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

 * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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package com.sun.tools.javac.api;

import javax.lang.model.element.Element;

import javax.lang.model.element.ExecutableElement;

import javax.lang.model.element.TypeElement;

import com.sun.tools.javac.comp.AttrContext;

import com.sun.tools.javac.comp.Env;

/**

 * Provides an implementation of Scope.

 *

 * <p><b>This is NOT part of any supported API.

 * If you write code that depends on this, you do so at your own

 * risk.  This code and its internal interfaces are subject to change

 * or deletion without notice.</b></p>

 *

 * @author Jonathan Gibbons;

 */

public class JavacScope implements com.sun.source.tree.Scope {

    static JavacScope create(Env<AttrContext> env) {

        if (env.outer == null || env.outer == env) {

            //the "top-level" scope needs to return both imported and defined elements

            //see test CheckLocalElements

            return new JavacScope(env) {

                public Iterable<? extends Element> getLocalElements() {

                    return env.toplevel.namedImportScope.getSymbols();

                }

            };

        } else {

            return new JavacScope(env);

        }

    }

    protected final Env<AttrContext> env;

    private JavacScope(Env<AttrContext> env) {

        env.getClass(); // null-check

        this.env = env;

    }

    public JavacScope getEnclosingScope() {

        if (env.outer != null && env.outer != env) {

            return create(env.outer);

        } else {

            // synthesize an outermost "star-import" scope

            return new JavacScope(env) {

                public boolean isStarImportScope() {

                    return true;

                }

                public JavacScope getEnclosingScope() {

                    return null;

                }

                public Iterable<? extends Element> getLocalElements() {

                    return env.toplevel.starImportScope.getSymbols();

                }

            };

        }

    }

    public TypeElement getEnclosingClass() {

        // hide the dummy class that javac uses to enclose the top level declarations

        return (env.outer == null || env.outer == env ? null : env.enclClass.sym);

    }

    public ExecutableElement getEnclosingMethod() {

        return (env.enclMethod == null ? null : env.enclMethod.sym);

    }

    public Iterable<? extends Element> getLocalElements() {

        return env.info.getLocalElements();

    }

    public Env<AttrContext> getEnv() {

        return env;

    }

    public boolean isStarImportScope() {

        return false;

    }

    public boolean equals(Object other) {

        if (other instanceof JavacScope) {

            JavacScope s = (JavacScope) other;

            return (env.equals(s.env)

                && isStarImportScope() == s.isStarImportScope());

        } else

            return false;

    }

    public int hashCode() {

        return env.hashCode() + (isStarImportScope() ? 1 : 0);

    }

    public String toString() {

        return "JavacScope[env=" + env + ",starImport=" + isStarImportScope() + "]";

    }

}