Java tutorial
/* * @(#)$Id: CountingOutputStream.java 3619 2008-03-26 07:23:03Z yui $ * * Copyright 2006-2008 Makoto YUI * * 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. * * Contributors: * Makoto YUI - initial implementation */ //package xbird.util.io; import java.io.IOException; import java.io.OutputStream; /** * * <DIV lang="en"></DIV> * <DIV lang="ja"></DIV> * * @author Makoto YUI (yuin405 AT gmail.com) */ public class CountingOutputStream extends OutputStream { private final OutputStream proxy; private long count = 0; public CountingOutputStream(final OutputStream out) { assert (out != null); this.proxy = out; } public void reset() { this.count = 0; } public long getCount() { if (count >= 0 && count <= Long.MAX_VALUE) { return count; } throw new IllegalStateException("out bytes exceeds Long.MAX_VALUE: " + count); } @Override public void write(int b) throws IOException { ++count; // just 1 byte is wrote proxy.write(b); } @Override public void write(byte[] b, int off, int len) throws IOException { count += len; proxy.write(b, off, len); } @Override public void write(byte[] b) throws IOException { count += b.length; proxy.write(b); } @Override public void close() throws IOException { proxy.close(); } @Override public void flush() throws IOException { proxy.flush(); } }