YellOnFlushAndCloseOutputStream.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.commons.io.testtools;

import java.io.IOException;
import java.io.OutputStream;

import junit.framework.AssertionFailedError;

import org.apache.commons.io.output.ProxyOutputStream;

/**
 * Helper class for checking behaviour of IO classes.
 * 
 * @author <a href="mailto:jeremias@apache.org">Jeremias Maerki</a>
 */
public class YellOnFlushAndCloseOutputStream extends ProxyOutputStream {

    private boolean yellForFlush;
    private boolean yellForClose;

    /**
     * @param proxy OutputStream to delegate to.
     * @param yellForFlush True if flush() is forbidden
     * @param yellForClose True if close() is forbidden
     */
    public YellOnFlushAndCloseOutputStream(OutputStream proxy, boolean yellForFlush, boolean yellForClose) {
        super(proxy);
        this.yellForFlush = yellForFlush;
        this.yellForClose = yellForClose;
    }

    /** @see java.io.OutputStream#flush() */
    public void flush() throws IOException {
        if (yellForFlush) {
            throw new AssertionFailedError("flush() was called on OutputStream");
        }
        super.flush();
    }

    /** @see java.io.OutputStream#close() */
    public void close() throws IOException {
        if (yellForClose) {
            throw new AssertionFailedError("close() was called on OutputStream");
        }
        super.close();
    }

    public void off() {
        yellForFlush = false;
        yellForClose = false;
    }

}