/*

 * Copyright (c) 1999, 2019, 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.comp;

import com.sun.tools.javac.tree.JCTree;

import com.sun.tools.javac.util.*;

import com.sun.tools.javac.code.*;

import com.sun.tools.javac.code.Scope.WriteableScope;

import com.sun.tools.javac.comp.DeferredAttr.AttributionMode;

/** Contains information specific to the attribute and enter

 *  passes, to be used in place of the generic field in environments.

 *

 *  <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>

 */

public class AttrContext {

    /** The scope of local symbols.

     */

    WriteableScope scope = null;

    /** The number of enclosing `static' modifiers.

     */

    int staticLevel = 0;

    /** Is this an environment for a this(...) or super(...) call?

     */

    boolean isSelfCall = false;

    /** Are we evaluating the selector of a `super' or type name?

     */

    boolean selectSuper = false;

    /** Is the current target of lambda expression or method reference serializable or is this a

     *  serializable class?

     */

    boolean isSerializable = false;

    /** Is this a lambda environment?

     */

    boolean isLambda = false;

    /** Is this a speculative attribution environment?

     */

    AttributionMode attributionMode = AttributionMode.FULL;

    /**

     *  Is this an attribution environment for an anonymous class instantiated using <> ?

     */

    boolean isAnonymousDiamond = false;

    /**

     *  Is this an attribution environment for an instance creation expression?

     */

    boolean isNewClass = false;

    /** Indicate if the type being visited is a service implementation

     */

    boolean visitingServiceImplementation = false;

    /** Are arguments to current function applications boxed into an array for varargs?

     */

    Resolve.MethodResolutionPhase pendingResolutionPhase = null;

    /** A record of the lint/SuppressWarnings currently in effect

     */

    Lint lint;

    /** The variable whose initializer is being attributed

     * useful for detecting self-references in variable initializers

     */

    Symbol enclVar = null;

    /** ResultInfo to be used for attributing 'return' statement expressions

     * (set by Attr.visitMethod and Attr.visitLambda)

     */

    Attr.ResultInfo returnResult = null;

    /** ResultInfo to be used for attributing 'yield' statement expressions

     * (set by Attr.visitSwitchExpression)

     */

    Attr.ResultInfo yieldResult = null;

    /** Symbol corresponding to the site of a qualified default super call

     */

    Type defaultSuperCallSite = null;

    /** Tree that when non null, is to be preferentially used in diagnostics.

     *  Usually Env<AttrContext>.tree is the tree to be referred to in messages,

     *  but this may not be true during the window a method is looked up in enclosing

     *  contexts (JDK-8145466)

     */

    JCTree preferredTreeForDiagnostics;

    /** Duplicate this context, replacing scope field and copying all others.

     */

    AttrContext dup(WriteableScope scope) {

        AttrContext info = new AttrContext();

        info.scope = scope;

        info.staticLevel = staticLevel;

        info.isSelfCall = isSelfCall;

        info.selectSuper = selectSuper;

        info.pendingResolutionPhase = pendingResolutionPhase;

        info.lint = lint;

        info.enclVar = enclVar;

        info.returnResult = returnResult;

        info.yieldResult = yieldResult;

        info.defaultSuperCallSite = defaultSuperCallSite;

        info.isSerializable = isSerializable;

        info.isLambda = isLambda;

        info.attributionMode = attributionMode;

        info.isAnonymousDiamond = isAnonymousDiamond;

        info.isNewClass = isNewClass;

        info.preferredTreeForDiagnostics = preferredTreeForDiagnostics;

        info.visitingServiceImplementation = visitingServiceImplementation;

        return info;

    }

    /** Duplicate this context, copying all fields.

     */

    AttrContext dup() {

        return dup(scope);

    }

    public Iterable<Symbol> getLocalElements() {

        if (scope == null)

            return List.nil();

        return scope.getSymbols();

    }

    boolean lastResolveVarargs() {

        return pendingResolutionPhase != null &&

                pendingResolutionPhase.isVarargsRequired();

    }

    @Override

    public String toString() {

        return "AttrContext[" + scope.toString() + "]";

    }

}