Marker.java

/*
 * 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.felix.gogo.runtime.threadio;

import java.io.InputStream;
import java.io.PrintStream;

public class Marker
{
    final Marker previous;
    InputStream in;
    PrintStream out;
    PrintStream err;
    volatile boolean deactivated;

    public Marker(InputStream in, PrintStream out, PrintStream err, Marker previous)
    {
        this.previous = previous;
        this.in = in;
        this.out = out;
        this.err = err;
    }

    public InputStream getIn()
    {
        return deactivated ? previous.getIn() : in;
    }

    public PrintStream getOut()
    {
        return deactivated ? previous.getOut() : out;
    }

    public PrintStream getErr()
    {
        return deactivated ? previous.getErr() : err;
    }

    void deactivate()
    {
        deactivated = true;
        // Set to null for garbage collection
        in = null;
        out = null;
        err = null;
    }
}