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	/*
	* Copyright (c) 2000, 2007, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package javax.imageio.stream;

	import java.io.IOException;
	import java.io.UTFDataFormatException;
	import java.nio.ByteOrder;

	/**
	* An abstract class implementing the <code>ImageOutputStream</code> interface.
	* This class is designed to reduce the number of methods that must
	* be implemented by subclasses.
	*
	*/
	public abstract class ImageOutputStreamImpl
	extends ImageInputStreamImpl
	implements ImageOutputStream {

	/**
	* Constructs an <code>ImageOutputStreamImpl</code>.
	*/
	public ImageOutputStreamImpl() {
	}

	public abstract void write(int b) throws IOException;

	public void write(byte b[]) throws IOException {
	write(b, 0, b.length);
	}

	public abstract void write(byte b[], int off, int len) throws IOException;

	public void writeBoolean(boolean v) throws IOException {
	write(v ? 1 : 0);
	}

	public void writeByte(int v) throws IOException {
	write(v);
	}

	public void writeShort(int v) throws IOException {
	if (byteOrder == ByteOrder.BIG_ENDIAN) {
	byteBuf[0] = (byte)(v >>> 8);
	byteBuf[1] = (byte)(v >>> 0);
	} else {
	byteBuf[0] = (byte)(v >>> 0);
	byteBuf[1] = (byte)(v >>> 8);
	}
	write(byteBuf, 0, 2);
	}

	public void writeChar(int v) throws IOException {
	writeShort(v);
	}

	public void writeInt(int v) throws IOException {
	if (byteOrder == ByteOrder.BIG_ENDIAN) {
	byteBuf[0] = (byte)(v >>> 24);
	byteBuf[1] = (byte)(v >>> 16);
	byteBuf[2] = (byte)(v >>> 8);
	byteBuf[3] = (byte)(v >>> 0);
	} else {
	byteBuf[0] = (byte)(v >>> 0);
	byteBuf[1] = (byte)(v >>> 8);
	byteBuf[2] = (byte)(v >>> 16);
	byteBuf[3] = (byte)(v >>> 24);
	}
	write(byteBuf, 0, 4);
	}

	public void writeLong(long v) throws IOException {
	if (byteOrder == ByteOrder.BIG_ENDIAN) {
	byteBuf[0] = (byte)(v >>> 56);
	byteBuf[1] = (byte)(v >>> 48);
	byteBuf[2] = (byte)(v >>> 40);
	byteBuf[3] = (byte)(v >>> 32);
	byteBuf[4] = (byte)(v >>> 24);
	byteBuf[5] = (byte)(v >>> 16);
	byteBuf[6] = (byte)(v >>> 8);
	byteBuf[7] = (byte)(v >>> 0);
	} else {
	byteBuf[0] = (byte)(v >>> 0);
	byteBuf[1] = (byte)(v >>> 8);
	byteBuf[2] = (byte)(v >>> 16);
	byteBuf[3] = (byte)(v >>> 24);
	byteBuf[4] = (byte)(v >>> 32);
	byteBuf[5] = (byte)(v >>> 40);
	byteBuf[6] = (byte)(v >>> 48);
	byteBuf[7] = (byte)(v >>> 56);
	}
	// REMIND: Once 6277756 is fixed, we should do a bulk write of all 8
	// bytes here as we do in writeShort() and writeInt() for even better
	// performance. For now, two bulk writes of 4 bytes each is still
	// faster than 8 individual write() calls (see 6347575 for details).
	write(byteBuf, 0, 4);
	write(byteBuf, 4, 4);
	}

	public void writeFloat(float v) throws IOException {
	writeInt(Float.floatToIntBits(v));
	}

	public void writeDouble(double v) throws IOException {
	writeLong(Double.doubleToLongBits(v));
	}

	public void writeBytes(String s) throws IOException {
	int len = s.length();
	for (int i = 0 ; i < len ; i++) {
	write((byte)s.charAt(i));
	}
	}

	public void writeChars(String s) throws IOException {
	int len = s.length();

	byte[] b = new byte[len*2];
	int boff = 0;
	if (byteOrder == ByteOrder.BIG_ENDIAN) {
	for (int i = 0; i < len ; i++) {
	int v = s.charAt(i);
	b[boff++] = (byte)(v >>> 8);
	b[boff++] = (byte)(v >>> 0);
	}
	} else {
	for (int i = 0; i < len ; i++) {
	int v = s.charAt(i);
	b[boff++] = (byte)(v >>> 0);
	b[boff++] = (byte)(v >>> 8);
	}
	}

	write(b, 0, len*2);
	}

	public void writeUTF(String s) throws IOException {
	int strlen = s.length();
	int utflen = 0;
	char[] charr = new char[strlen];
	int c, boff = 0;

	s.getChars(0, strlen, charr, 0);

	for (int i = 0; i < strlen; i++) {
	c = charr[i];
	if ((c >= 0x0001) && (c <= 0x007F)) {
	utflen++;
	} else if (c > 0x07FF) {
	utflen += 3;
	} else {
	utflen += 2;
	}
	}

	if (utflen > 65535) {
	throw new UTFDataFormatException("utflen > 65536!");
	}

	byte[] b = new byte[utflen+2];
	b[boff++] = (byte) ((utflen >>> 8) & 0xFF);
	b[boff++] = (byte) ((utflen >>> 0) & 0xFF);
	for (int i = 0; i < strlen; i++) {
	c = charr[i];
	if ((c >= 0x0001) && (c <= 0x007F)) {
	b[boff++] = (byte) c;
	} else if (c > 0x07FF) {
	b[boff++] = (byte) (0xE0 \| ((c >> 12) & 0x0F));
	b[boff++] = (byte) (0x80 \| ((c >> 6) & 0x3F));
	b[boff++] = (byte) (0x80 \| ((c >> 0) & 0x3F));
	} else {
	b[boff++] = (byte) (0xC0 \| ((c >> 6) & 0x1F));
	b[boff++] = (byte) (0x80 \| ((c >> 0) & 0x3F));
	}
	}
	write(b, 0, utflen + 2);
	}

	public void writeShorts(short[] s, int off, int len) throws IOException {
	// Fix 4430357 - if off + len < 0, overflow occurred
	if (off < 0 \|\| len < 0 \|\| off + len > s.length \|\| off + len < 0) {
	throw new IndexOutOfBoundsException
	("off < 0 \|\| len < 0 \|\| off + len > s.length!");
	}

	byte[] b = new byte[len*2];
	int boff = 0;
	if (byteOrder == ByteOrder.BIG_ENDIAN) {
	for (int i = 0; i < len; i++) {
	short v = s[off + i];
	b[boff++] = (byte)(v >>> 8);
	b[boff++] = (byte)(v >>> 0);
	}
	} else {
	for (int i = 0; i < len; i++) {
	short v = s[off + i];
	b[boff++] = (byte)(v >>> 0);
	b[boff++] = (byte)(v >>> 8);
	}
	}

	write(b, 0, len*2);
	}

	public void writeChars(char[] c, int off, int len) throws IOException {
	// Fix 4430357 - if off + len < 0, overflow occurred
	if (off < 0 \|\| len < 0 \|\| off + len > c.length \|\| off + len < 0) {
	throw new IndexOutOfBoundsException
	("off < 0 \|\| len < 0 \|\| off + len > c.length!");
	}

	byte[] b = new byte[len*2];
	int boff = 0;
	if (byteOrder == ByteOrder.BIG_ENDIAN) {
	for (int i = 0; i < len; i++) {
	char v = c[off + i];
	b[boff++] = (byte)(v >>> 8);
	b[boff++] = (byte)(v >>> 0);
	}
	} else {
	for (int i = 0; i < len; i++) {
	char v = c[off + i];
	b[boff++] = (byte)(v >>> 0);
	b[boff++] = (byte)(v >>> 8);
	}
	}

	write(b, 0, len*2);
	}

	public void writeInts(int[] i, int off, int len) throws IOException {
	// Fix 4430357 - if off + len < 0, overflow occurred
	if (off < 0 \|\| len < 0 \|\| off + len > i.length \|\| off + len < 0) {
	throw new IndexOutOfBoundsException
	("off < 0 \|\| len < 0 \|\| off + len > i.length!");
	}

	byte[] b = new byte[len*4];
	int boff = 0;
	if (byteOrder == ByteOrder.BIG_ENDIAN) {
	for (int j = 0; j < len; j++) {
	int v = i[off + j];
	b[boff++] = (byte)(v >>> 24);
	b[boff++] = (byte)(v >>> 16);
	b[boff++] = (byte)(v >>> 8);
	b[boff++] = (byte)(v >>> 0);
	}
	} else {
	for (int j = 0; j < len; j++) {
	int v = i[off + j];
	b[boff++] = (byte)(v >>> 0);
	b[boff++] = (byte)(v >>> 8);
	b[boff++] = (byte)(v >>> 16);
	b[boff++] = (byte)(v >>> 24);
	}
	}

	write(b, 0, len*4);
	}

	public void writeLongs(long[] l, int off, int len) throws IOException {
	// Fix 4430357 - if off + len < 0, overflow occurred
	if (off < 0 \|\| len < 0 \|\| off + len > l.length \|\| off + len < 0) {
	throw new IndexOutOfBoundsException
	("off < 0 \|\| len < 0 \|\| off + len > l.length!");
	}

	byte[] b = new byte[len*8];
	int boff = 0;
	if (byteOrder == ByteOrder.BIG_ENDIAN) {
	for (int i = 0; i < len; i++) {
	long v = l[off + i];
	b[boff++] = (byte)(v >>> 56);
	b[boff++] = (byte)(v >>> 48);
	b[boff++] = (byte)(v >>> 40);
	b[boff++] = (byte)(v >>> 32);
	b[boff++] = (byte)(v >>> 24);
	b[boff++] = (byte)(v >>> 16);
	b[boff++] = (byte)(v >>> 8);
	b[boff++] = (byte)(v >>> 0);
	}
	} else {
	for (int i = 0; i < len; i++) {
	long v = l[off + i];
	b[boff++] = (byte)(v >>> 0);
	b[boff++] = (byte)(v >>> 8);
	b[boff++] = (byte)(v >>> 16);
	b[boff++] = (byte)(v >>> 24);
	b[boff++] = (byte)(v >>> 32);
	b[boff++] = (byte)(v >>> 40);
	b[boff++] = (byte)(v >>> 48);
	b[boff++] = (byte)(v >>> 56);
	}
	}

	write(b, 0, len*8);
	}

	public void writeFloats(float[] f, int off, int len) throws IOException {
	// Fix 4430357 - if off + len < 0, overflow occurred
	if (off < 0 \|\| len < 0 \|\| off + len > f.length \|\| off + len < 0) {
	throw new IndexOutOfBoundsException
	("off < 0 \|\| len < 0 \|\| off + len > f.length!");
	}

	byte[] b = new byte[len*4];
	int boff = 0;
	if (byteOrder == ByteOrder.BIG_ENDIAN) {
	for (int i = 0; i < len; i++) {
	int v = Float.floatToIntBits(f[off + i]);
	b[boff++] = (byte)(v >>> 24);
	b[boff++] = (byte)(v >>> 16);
	b[boff++] = (byte)(v >>> 8);
	b[boff++] = (byte)(v >>> 0);
	}
	} else {
	for (int i = 0; i < len; i++) {
	int v = Float.floatToIntBits(f[off + i]);
	b[boff++] = (byte)(v >>> 0);
	b[boff++] = (byte)(v >>> 8);
	b[boff++] = (byte)(v >>> 16);
	b[boff++] = (byte)(v >>> 24);
	}
	}

	write(b, 0, len*4);
	}

	public void writeDoubles(double[] d, int off, int len) throws IOException {
	// Fix 4430357 - if off + len < 0, overflow occurred
	if (off < 0 \|\| len < 0 \|\| off + len > d.length \|\| off + len < 0) {
	throw new IndexOutOfBoundsException
	("off < 0 \|\| len < 0 \|\| off + len > d.length!");
	}

	byte[] b = new byte[len*8];
	int boff = 0;
	if (byteOrder == ByteOrder.BIG_ENDIAN) {
	for (int i = 0; i < len; i++) {
	long v = Double.doubleToLongBits(d[off + i]);
	b[boff++] = (byte)(v >>> 56);
	b[boff++] = (byte)(v >>> 48);
	b[boff++] = (byte)(v >>> 40);
	b[boff++] = (byte)(v >>> 32);
	b[boff++] = (byte)(v >>> 24);
	b[boff++] = (byte)(v >>> 16);
	b[boff++] = (byte)(v >>> 8);
	b[boff++] = (byte)(v >>> 0);
	}
	} else {
	for (int i = 0; i < len; i++) {
	long v = Double.doubleToLongBits(d[off + i]);
	b[boff++] = (byte)(v >>> 0);
	b[boff++] = (byte)(v >>> 8);
	b[boff++] = (byte)(v >>> 16);
	b[boff++] = (byte)(v >>> 24);
	b[boff++] = (byte)(v >>> 32);
	b[boff++] = (byte)(v >>> 40);
	b[boff++] = (byte)(v >>> 48);
	b[boff++] = (byte)(v >>> 56);
	}
	}

	write(b, 0, len*8);
	}

	public void writeBit(int bit) throws IOException {
	writeBits((1L & bit), 1);
	}

	public void writeBits(long bits, int numBits) throws IOException {
	checkClosed();

	if (numBits < 0 \|\| numBits > 64) {
	throw new IllegalArgumentException("Bad value for numBits!");
	}
	if (numBits == 0) {
	return;
	}

	// Prologue: deal with pre-existing bits

	// Bug 4499158, 4507868 - if we're at the beginning of the stream
	// and the bit offset is 0, there can't be any pre-existing bits
	if ((getStreamPosition() > 0) \|\| (bitOffset > 0)) {
	int offset = bitOffset; // read() will reset bitOffset
	int partialByte = read();
	if (partialByte != -1) {
	seek(getStreamPosition() - 1);
	} else {
	partialByte = 0;
	}

	if (numBits + offset < 8) {
	// Notch out the partial byte and drop in the new bits
	int shift = 8 - (offset+numBits);
	int mask = -1 >>> (32 - numBits);
	partialByte &= ~(mask << shift); // Clear out old bits
	partialByte \|= ((bits & mask) << shift); // Or in new ones
	write(partialByte);
	seek(getStreamPosition() - 1);
	bitOffset = offset + numBits;
	numBits = 0; // Signal that we are done
	} else {
	// Fill out the partial byte and reduce numBits
	int num = 8 - offset;
	int mask = -1 >>> (32 - num);
	partialByte &= ~mask; // Clear out bits
	partialByte \|= ((bits >> (numBits - num)) & mask);
	// Note that bitOffset is already 0, so there is no risk
	// of this advancing to the next byte
	write(partialByte);
	numBits -= num;
	}
	}

	// Now write any whole bytes
	if (numBits > 7) {
	int extra = numBits % 8;
	for (int numBytes = numBits / 8; numBytes > 0; numBytes--) {
	int shift = (numBytes-1)*8+extra;
	int value = (int) ((shift == 0)
	? bits & 0xFF
	: (bits>>shift) & 0xFF);
	write(value);
	}
	numBits = extra;
	}

	// Epilogue: write out remaining partial byte, if any
	// Note that we may be at EOF, in which case we pad with 0,
	// or not, in which case we must preserve the existing bits
	if (numBits != 0) {
	// If we are not at the end of the file, read the current byte
	// If we are at the end of the file, initialize our byte to 0.
	int partialByte = 0;
	partialByte = read();
	if (partialByte != -1) {
	seek(getStreamPosition() - 1);
	}
	// Fix 4494976: writeBit(int) does not pad the remainder
	// of the current byte with 0s
	else { // EOF
	partialByte = 0;
	}

	int shift = 8 - numBits;
	int mask = -1 >>> (32 - numBits);
	partialByte &= ~(mask << shift);
	partialByte \|= (bits & mask) << shift;
	// bitOffset is always already 0 when we get here.
	write(partialByte);
	seek(getStreamPosition() - 1);
	bitOffset = numBits;
	}
	}

	/**
	* If the bit offset is non-zero, forces the remaining bits
	* in the current byte to 0 and advances the stream position
	* by one. This method should be called by subclasses at the
	* beginning of the <code>write(int)</code> and
	* <code>write(byte[], int, int)</code> methods.
	*
	* @exception IOException if an I/O error occurs.
	*/
	protected final void flushBits() throws IOException {
	checkClosed();
	if (bitOffset != 0) {
	int offset = bitOffset;
	int partialByte = read(); // Sets bitOffset to 0
	if (partialByte < 0) {
	// Fix 4465683: When bitOffset is set
	// to something non-zero beyond EOF,
	// we should set that whole byte to
	// zero and write it to stream.
	partialByte = 0;
	bitOffset = 0;
	}
	else {
	seek(getStreamPosition() - 1);
	partialByte &= -1 << (8 - offset);
	}
	write(partialByte);
	}
	}

	}

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