/*
* Copyright (c) 2008, Harald Kuhr
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* * Neither the name of the copyright holder nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* From http://www.cafeaulait.org/books/javaio/ioexamples/index.html:
*
* Please feel free to use any fragment of this code you need in your own work.
* As far as I am concerned, it's in the public domain. No permission is necessary
* or required. Credit is always appreciated if you use a large chunk or base a
* significant product on one of my examples, but that's not required either.
*
* Elliotte Rusty Harold
*/
package com.twelvemonkeys.io;
import com.twelvemonkeys.lang.
Validate;
import java.io.*;
/**
* A little endian output stream writes primitive Java numbers
* and characters to an output stream in a little endian format.
* <p/>
* The standard {@code java.io.DataOutputStream} class which this class
* imitates uses big endian integers.
* <p/>
* <em>Warning:
* <!-- Beware of little indians! -->
* The {@code DataInput} and {@code DataOutput} interfaces
* specifies big endian byte order in their documentation.
* This means that this class is, strictly speaking, not a proper
* implementation. However, I don't see a reason for the these interfaces to
* specify the byte order of their underlying representations.
* </em>
*
* @see com.twelvemonkeys.io.LittleEndianRandomAccessFile
* @see java.io.DataOutputStream
* @see java.io.DataInput
* @see java.io.DataOutput
*
* @author Elliotte Rusty Harold
* @version 1.0.1, 19 May 1999
*/
public class
LittleEndianDataOutputStream extends
FilterOutputStream implements
DataOutput {
/**
* The number of bytes written so far to the little endian output stream.
*/
protected int
bytesWritten;
/**
* Creates a new little endian output stream and chains it to the
* output stream specified by the {@code pStream} argument.
*
* @param pStream the underlying output stream.
* @see java.io.FilterOutputStream#out
*/
public
LittleEndianDataOutputStream(
OutputStream pStream) {
super(
Validate.
notNull(
pStream, "stream"));
}
/**
* Writes the specified byte value to the underlying output stream.
*
* @param pByte the {@code byte} value to be written.
* @throws IOException if the underlying stream throws an IOException.
*/
public synchronized void
write(int
pByte) throws
IOException {
out.
write(
pByte);
bytesWritten++;
}
/**
* Writes {@code pLength} bytes from the specified byte array
* starting at {@code pOffset} to the underlying output stream.
*
* @param pBytes the data.
* @param pOffset the start offset in the data.
* @param pLength the number of bytes to write.
* @throws IOException if the underlying stream throws an IOException.
*/
public synchronized void
write(byte[]
pBytes, int
pOffset, int
pLength) throws
IOException {
out.
write(
pBytes,
pOffset,
pLength);
bytesWritten +=
pLength;
}
/**
* Writes a {@code boolean} to the underlying output stream as
* a single byte. If the argument is true, the byte value 1 is written.
* If the argument is false, the byte value {@code 0} in written.
*
* @param pBoolean the {@code boolean} value to be written.
* @throws IOException if the underlying stream throws an IOException.
*/
public void
writeBoolean(boolean
pBoolean) throws
IOException {
if (
pBoolean) {
write(1);
}
else {
write(0);
}
}
/**
* Writes out a {@code byte} to the underlying output stream
*
* @param pByte the {@code byte} value to be written.
* @throws IOException if the underlying stream throws an IOException.
*/
public void
writeByte(int
pByte) throws
IOException {
out.
write(
pByte);
bytesWritten++;
}
/**
* Writes a two byte {@code short} to the underlying output stream in
* little endian order, low byte first.
*
* @param pShort the {@code short} to be written.
* @throws IOException if the underlying stream throws an IOException.
*/
public void
writeShort(int
pShort) throws
IOException {
out.
write(
pShort & 0xFF);
out.
write((
pShort >>> 8) & 0xFF);
bytesWritten += 2;
}
/**
* Writes a two byte {@code char} to the underlying output stream
* in little endian order, low byte first.
*
* @param pChar the {@code char} value to be written.
* @throws IOException if the underlying stream throws an IOException.
*/
public void
writeChar(int
pChar) throws
IOException {
out.
write(
pChar & 0xFF);
out.
write((
pChar >>> 8) & 0xFF);
bytesWritten += 2;
}
/**
* Writes a four-byte {@code int} to the underlying output stream
* in little endian order, low byte first, high byte last
*
* @param pInt the {@code int} to be written.
* @throws IOException if the underlying stream throws an IOException.
*/
public void
writeInt(int
pInt) throws
IOException {
out.
write(
pInt & 0xFF);
out.
write((
pInt >>> 8) & 0xFF);
out.
write((
pInt >>> 16) & 0xFF);
out.
write((
pInt >>> 24) & 0xFF);
bytesWritten += 4;
}
/**
* Writes an eight-byte {@code long} to the underlying output stream
* in little endian order, low byte first, high byte last
*
* @param pLong the {@code long} to be written.
* @throws IOException if the underlying stream throws an IOException.
*/
public void
writeLong(long
pLong) throws
IOException {
out.
write((int)
pLong & 0xFF);
out.
write((int) (
pLong >>> 8) & 0xFF);
out.
write((int) (
pLong >>> 16) & 0xFF);
out.
write((int) (
pLong >>> 24) & 0xFF);
out.
write((int) (
pLong >>> 32) & 0xFF);
out.
write((int) (
pLong >>> 40) & 0xFF);
out.
write((int) (
pLong >>> 48) & 0xFF);
out.
write((int) (
pLong >>> 56) & 0xFF);
bytesWritten += 8;
}
/**
* Writes a 4 byte Java float to the underlying output stream in
* little endian order.
*
* @param f the {@code float} value to be written.
* @throws IOException if an I/O error occurs.
*/
public final void
writeFloat(float
f) throws
IOException {
writeInt(
Float.
floatToIntBits(
f));
}
/**
* Writes an 8 byte Java double to the underlying output stream in
* little endian order.
*
* @param d the {@code double} value to be written.
* @throws IOException if an I/O error occurs.
*/
public final void
writeDouble(double
d) throws
IOException {
writeLong(
Double.
doubleToLongBits(
d));
}
/**
* Writes a string to the underlying output stream as a sequence of
* bytes. Each character is written to the data output stream as
* if by the {@link #writeByte(int)} method.
*
* @param pString the {@code String} value to be written.
* @throws IOException if the underlying stream throws an IOException.
* @see #writeByte(int)
* @see #out
*/
public void
writeBytes(
String pString) throws
IOException {
int
length =
pString.
length();
for (int
i = 0;
i <
length;
i++) {
out.
write((byte)
pString.
charAt(
i));
}
bytesWritten +=
length;
}
/**
* Writes a string to the underlying output stream as a sequence of
* characters. Each character is written to the data output stream as
* if by the {@code writeChar} method.
*
* @param pString a {@code String} value to be written.
* @throws IOException if the underlying stream throws an IOException.
* @see #writeChar(int)
* @see #out
*/
public void
writeChars(
String pString) throws
IOException {
int
length =
pString.
length();
for (int
i = 0;
i <
length;
i++) {
int
c =
pString.
charAt(
i);
out.
write(
c & 0xFF);
out.
write((
c >>> 8) & 0xFF);
}
bytesWritten +=
length * 2;
}
/**
* Writes a string of no more than 65,535 characters
* to the underlying output stream using UTF-8
* encoding. This method first writes a two byte short
* in <b>big</b> endian order as required by the
* UTF-8 specification. This gives the number of bytes in the
* UTF-8 encoded version of the string, not the number of characters
* in the string. Next each character of the string is written
* using the UTF-8 encoding for the character.
*
* @param pString the string to be written.
* @throws UTFDataFormatException if the string is longer than
* 65,535 characters.
* @throws IOException if the underlying stream throws an IOException.
*/
public void
writeUTF(
String pString) throws
IOException {
int
numchars =
pString.
length();
int
numbytes = 0;
for (int
i = 0;
i <
numchars;
i++) {
int
c =
pString.
charAt(
i);
if ((
c >= 0x0001) && (
c <= 0x007F)) {
numbytes++;
}
else if (
c > 0x07FF) {
numbytes += 3;
}
else {
numbytes += 2;
}
}
if (
numbytes > 65535) {
throw new
UTFDataFormatException();
}
out.
write((
numbytes >>> 8) & 0xFF);
out.
write(
numbytes & 0xFF);
for (int
i = 0;
i <
numchars;
i++) {
int
c =
pString.
charAt(
i);
if ((
c >= 0x0001) && (
c <= 0x007F)) {
out.
write(
c);
}
else if (
c > 0x07FF) {
out.
write(0xE0 | ((
c >> 12) & 0x0F));
out.
write(0x80 | ((
c >> 6) & 0x3F));
out.
write(0x80 | (
c & 0x3F));
bytesWritten += 2;
}
else {
out.
write(0xC0 | ((
c >> 6) & 0x1F));
out.
write(0x80 | (
c & 0x3F));
bytesWritten += 1;
}
}
bytesWritten +=
numchars + 2;
}
/**
* Returns the number of bytes written to this little endian output stream.
* (This class is not thread-safe with respect to this method. It is
* possible that this number is temporarily less than the actual
* number of bytes written.)
* @return the value of the {@code written} field.
* @see #bytesWritten
*/
public int
size() {
return
bytesWritten;
}
}