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package javax.imageio.stream;

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

An abstract class implementing the ImageOutputStream interface. This class is designed to reduce the number of methods that must be implemented by subclasses.
/** * An abstract class implementing the {@code ImageOutputStream} 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 ImageOutputStreamImpl.
/** * Constructs an {@code ImageOutputStreamImpl}. */
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 write(int) and write(byte[], int, int) methods.
Throws:
/** * 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)} and * {@code write(byte[], int, int)} 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); } } }