/*
 * 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 static com.google.common.base.Preconditions.checkNotNull;

import com.google.common.annotations.Beta;
import com.google.common.annotations.GwtIncompatible;
import java.io.FilterOutputStream;
import java.io.IOException;
import java.io.OutputStream;

An OutputStream that counts the number of bytes written.
Author:Chris Nokleberg
Since:1.0
/** * An OutputStream that counts the number of bytes written. * * @author Chris Nokleberg * @since 1.0 */
@Beta @GwtIncompatible public final class CountingOutputStream extends FilterOutputStream { private long count;
Wraps another output stream, counting the number of bytes written.
Params:
  • out – the output stream to be wrapped
/** * Wraps another output stream, counting the number of bytes written. * * @param out the output stream to be wrapped */
public CountingOutputStream(OutputStream out) { super(checkNotNull(out)); }
Returns the number of bytes written.
/** 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(); } }