/*
* Copyright (C) 2007 The Guava Authors
*
* Licensed 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 com.google.common.io;
import com.google.common.annotations.Beta;
import java.io.FilterOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import javax.annotation.Nullable;
/**
* An OutputStream that counts the number of bytes written.
*
* @author Chris Nokleberg
* @since 1.0
*/
@Beta
public final class CountingOutputStream extends FilterOutputStream {
private long count;
/**
* Wraps another output stream, counting the number of bytes written.
*
* @param out the output stream to be wrapped
*/
public CountingOutputStream(@Nullable OutputStream out) {
super(out);
}
/** Returns the number of bytes written. */
public long getCount() {
return count;
}
@Override public void write(byte[] b, int off, int len) throws IOException {
out.write(b, off, len);
count += len;
}
@Override public void write(int b) throws IOException {
out.write(b);
count++;
}
// Overriding close() because FilterOutputStream's close() method pre-JDK8 has bad behavior:
// it silently ignores any exception thrown by flush(). Instead, just close the delegate stream.
// It should flush itself if necessary.
@Override public void close() throws IOException {
out.close();
}
}