/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 */
package org.apache.bcel.verifier.structurals;



This class represents a JVM execution frame; that means,
a local variable array and an operand stack.
/**
 * This class represents a JVM execution frame; that means,
 * a local variable array and an operand stack.
 *
 */

public class Frame{

    
For instance initialization methods, it is important to remember
which instance it is that is not initialized yet. It will be
initialized invoking another constructor later.
NULL means the instance already *is* initialized.
Deprecated:
Use the getter/setter to access the field as it may
be made private in a later release/**
     * For instance initialization methods, it is important to remember
     * which instance it is that is not initialized yet. It will be
     * initialized invoking another constructor later.
     * NULL means the instance already *is* initialized.
     * @deprecated Use the getter/setter to access the field as it may
     * be made private in a later release
     */
    @Deprecated
    protected static UninitializedObjectType _this;

    /**
     *
     */
    private final LocalVariables locals;

    /**
     *
     */
    private final OperandStack stack;

    /**
     *
     */
    public Frame(final int maxLocals, final int maxStack) {
        locals = new LocalVariables(maxLocals);
        stack = new OperandStack(maxStack);
    }

    /**
     *
     */
    public Frame(final LocalVariables locals, final OperandStack stack) {
        this.locals = locals;
        this.stack = stack;
    }

    /**
     *
     */
    @Override
    protected Object clone() {
        final Frame f = new Frame(locals.getClone(), stack.getClone());
        return f;
    }

    /**
     *
     */
    public Frame getClone() {
        return (Frame) clone();
    }

    /**
     *
     */
    public LocalVariables getLocals() {
        return locals;
    }

    /**
     *
     */
    public OperandStack getStack() {
        return stack;
    }

    
Returns:
a hash code value for the object./** @return a hash code value for the object.
     */
    @Override
    public int hashCode() { return stack.hashCode() ^ locals.hashCode(); }

    /**
     *
     */
    @Override
    public boolean equals(final Object o) {
        if (!(o instanceof Frame)) {
            return false; // implies "null" is non-equal.
        }
        final Frame f = (Frame) o;
        return this.stack.equals(f.stack) && this.locals.equals(f.locals);
    }

    
Returns a String representation of the Frame instance.
/**
     * Returns a String representation of the Frame instance.
     */
    @Override
    public String toString() {
        String s="Local Variables:\n";
        s += locals;
        s += "OperandStack:\n";
        s += stack;
        return s;
    }

    
Returns:
the _this
Since:
6.0/**
     * @return the _this
     * @since 6.0
     */
    public static UninitializedObjectType getThis() {
        return _this;
    }

    
Params:
_this – the _this to set
Since:
6.0/**
     * @param _this the _this to set
     * @since 6.0
     */
    public static void setThis(final UninitializedObjectType _this) {
        Frame._this = _this;
    }
}