com.groupbyinc.common.apache.commons.codec.binary.BaseNCodecOutputStream Maven / Gradle / Ivy
/*
* 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.codec.binary;
import static org.apache.commons.codec.binary.BaseNCodec.EOF;
import java.io.FilterOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import org.apache.commons.codec.binary.BaseNCodec.Context;
/**
* Abstract superclass for Base-N output streams.
*
* To write the EOF marker without closing the stream, call {@link #eof()} or use an Apache Commons IO CloseShieldOutputStream.
*
*
* @since 1.5
* @version $Id: BaseNCodecOutputStream.java 1744727 2016-05-20 12:43:52Z sebb $
*/
public class BaseNCodecOutputStream extends FilterOutputStream {
private final boolean doEncode;
private final BaseNCodec baseNCodec;
private final byte[] singleByte = new byte[1];
private final Context context = new Context();
// TODO should this be protected?
public BaseNCodecOutputStream(final OutputStream out, final BaseNCodec basedCodec, final boolean doEncode) {
super(out);
this.baseNCodec = basedCodec;
this.doEncode = doEncode;
}
/**
* Writes the specified byte to this output stream.
*
* @param i
* source byte
* @throws IOException
* if an I/O error occurs.
*/
@Override
public void write(final int i) throws IOException {
singleByte[0] = (byte) i;
write(singleByte, 0, 1);
}
/**
* Writes len bytes from the specified b array starting at offset to this
* output stream.
*
* @param b
* source byte array
* @param offset
* where to start reading the bytes
* @param len
* maximum number of bytes to write
*
* @throws IOException
* if an I/O error occurs.
* @throws NullPointerException
* if the byte array parameter is null
* @throws IndexOutOfBoundsException
* if offset, len or buffer size are invalid
*/
@Override
public void write(final byte b[], final int offset, final int len) throws IOException {
if (b == null) {
throw new NullPointerException();
} else if (offset < 0 || len < 0) {
throw new IndexOutOfBoundsException();
} else if (offset > b.length || offset + len > b.length) {
throw new IndexOutOfBoundsException();
} else if (len > 0) {
if (doEncode) {
baseNCodec.encode(b, offset, len, context);
} else {
baseNCodec.decode(b, offset, len, context);
}
flush(false);
}
}
/**
* Flushes this output stream and forces any buffered output bytes to be written out to the stream. If propagate is
* true, the wrapped stream will also be flushed.
*
* @param propagate
* boolean flag to indicate whether the wrapped OutputStream should also be flushed.
* @throws IOException
* if an I/O error occurs.
*/
private void flush(final boolean propagate) throws IOException {
final int avail = baseNCodec.available(context);
if (avail > 0) {
final byte[] buf = new byte[avail];
final int c = baseNCodec.readResults(buf, 0, avail, context);
if (c > 0) {
out.write(buf, 0, c);
}
}
if (propagate) {
out.flush();
}
}
/**
* Flushes this output stream and forces any buffered output bytes to be written out to the stream.
*
* @throws IOException
* if an I/O error occurs.
*/
@Override
public void flush() throws IOException {
flush(true);
}
/**
* Closes this output stream and releases any system resources associated with the stream.
*
* To write the EOF marker without closing the stream, call {@link #eof()} or use an
* Apache Commons IO CloseShieldOutputStream.
*
*
* @throws IOException
* if an I/O error occurs.
*/
@Override
public void close() throws IOException {
eof();
flush();
out.close();
}
/**
* Writes EOF.
*
* @throws IOException
* if an I/O error occurs.
* @since 1.11
*/
public void eof() throws IOException {
// Notify encoder of EOF (-1).
if (doEncode) {
baseNCodec.encode(singleByte, 0, EOF, context);
} else {
baseNCodec.decode(singleByte, 0, EOF, context);
}
}
}