/***
* Copyright 2002-2010 jamod development team
*
* 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 net.wimpi.modbus.io;
import java.io.FilterOutputStream;
import java.io.IOException;
import java.io.OutputStream;
/**
* Class implementing a specialized <tt>OutputStream</tt> which
* duplicates bytes written to the stream that resemble a
* frame token.
*
* Note that the "virtual" characters FRAME_START and FRAME_END
* are exceptions, they are translated to the respective tokens
* as given by the specification.
*
* @author Dieter Wimberger
* @version @version@ (@date@)
*
* @see ModbusBINTransport#FRAME_START
* @see ModbusBINTransport#FRAME_END
*/
public class BINOutputStream extends FilterOutputStream {
/**
* Constructs a new <tt>BINOutputStream</tt> instance
* writing to the given <tt>OutputStream</tt>.
*
* @param out a base output stream instance to be wrapped.
*/
public BINOutputStream(OutputStream out) {
super(out);
}// constructor
/**
* Writes a byte to the raw output stream.
* Bytes resembling a frame token will be duplicated.
*
* @param b the byte to be written as <tt>int</tt>.
* @throws java.io.IOException if an I/O error occurs.
*/
@Override
public void write(int b) throws IOException {
if (b == ModbusASCIITransport.FRAME_START) {
out.write(ModbusBINTransport.FRAME_START_TOKEN);
return;
} else if (b == ModbusASCIITransport.FRAME_END) {
out.write(ModbusBINTransport.FRAME_END_TOKEN);
return;
} else if (b == ModbusBINTransport.FRAME_START_TOKEN || b == ModbusBINTransport.FRAME_END_TOKEN) {
out.write(b);
out.write(b);
}
}// write
/**
* Writes an array of bytes to the raw output stream.
* Bytes resembling a frame token will be duplicated.
*
* @param data the <tt>byte[]</tt> to be written.
* @throws java.io.IOException if an I/O error occurs.
*/
@Override
public void write(byte[] data) throws IOException {
for (int i = 0; i < data.length; i++) {
write(data[i]);
}
}// write(byte[])
/**
* Writes an array of bytes to the raw output stream.
* Bytes resembling a frame token will be duplicated. *
*
* @param data the <tt>byte[]</tt> to be written.
* @param off the offset into the data to start writing from.
* @param len the number of bytes to be written from off.
*
* @throws java.io.IOException if an I/O error occurs.
*/
@Override
public void write(byte[] data, int off, int len) throws IOException {
for (int i = off; i < len; i++) {
write(data[i]);
}
}// write(byte[])
}// class BINOutputStream