nashorn/src/jdk/nashorn/internal/codegen/Label.java

/*
 * Copyright (c) 2010, 2013, 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
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */
package jdk.nashorn.internal.codegen;

import java.util.ArrayDeque;

import jdk.nashorn.internal.codegen.types.Type;

/**
 * Abstraction for labels, separating a label from the underlying
 * byte code emitter. Also augmenting label with e.g. a name
 * for easier debugging and reading code
 *
 * see -Dnashorn.codegen.debug, --log=codegen
 */
public class Label extends jdk.internal.org.objectweb.asm.Label {
    /** Name of this label */
    private final String name;

    /** Type stack at this label */
    private ArrayDeque<Type> stack;

    /**
     * Constructor
     *
     * @param name name of this label
     */
    public Label(final String name) {
        super();
        this.name = name;
    }

    /**
     * Copy constructor
     *
     * @param label a label to clone
     */
    public Label(final Label label) {
        super();
        this.name = label.name;
    }

    ArrayDeque<Type> getStack() {
        return stack;
    }

    void setStack(final ArrayDeque<Type> stack) {
        this.stack = stack;
    }

    @Override
    public String toString() {
        final StringBuilder sb = new StringBuilder();
        String s = super.toString();
        s = s.substring(1, s.length());
        sb.append(name).append('_').append(Long.toHexString(Long.parseLong(s)));

        return sb.toString();
    }
}