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src/java.desktop/share/classes/javax/imageio/stream/ImageOutputStreamImpl.java

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  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package javax.imageio.stream;
  27 
  28 import java.io.IOException;
  29 import java.io.UTFDataFormatException;
  30 import java.nio.ByteOrder;
  31 
  32 /**
  33  * An abstract class implementing the <code>ImageOutputStream</code> interface.
  34  * This class is designed to reduce the number of methods that must
  35  * be implemented by subclasses.
  36  *
  37  */
  38 public abstract class ImageOutputStreamImpl
  39     extends ImageInputStreamImpl
  40     implements ImageOutputStream {
  41 
  42     /**
  43      * Constructs an <code>ImageOutputStreamImpl</code>.
  44      */
  45     public ImageOutputStreamImpl() {
  46     }
  47 
  48     public abstract void write(int b) throws IOException;
  49 
  50     public void write(byte b[]) throws IOException {
  51         write(b, 0, b.length);
  52     }
  53 
  54     public abstract void write(byte b[], int off, int len) throws IOException;
  55 
  56     public void writeBoolean(boolean v) throws IOException {
  57         write(v ? 1 : 0);
  58     }
  59 
  60     public void writeByte(int v) throws IOException {
  61         write(v);
  62     }
  63 


 464             // of the current byte with 0s
 465             else { // EOF
 466                 partialByte = 0;
 467             }
 468 
 469             int shift = 8 - numBits;
 470             int mask = -1 >>> (32 - numBits);
 471             partialByte &= ~(mask << shift);
 472             partialByte |= (bits & mask) << shift;
 473             // bitOffset is always already 0 when we get here.
 474             write(partialByte);
 475             seek(getStreamPosition() - 1);
 476             bitOffset = numBits;
 477         }
 478     }
 479 
 480     /**
 481      * If the bit offset is non-zero, forces the remaining bits
 482      * in the current byte to 0 and advances the stream position
 483      * by one.  This method should be called by subclasses at the
 484      * beginning of the <code>write(int)</code> and
 485      * <code>write(byte[], int, int)</code> methods.
 486      *
 487      * @exception IOException if an I/O error occurs.
 488      */
 489     protected final void flushBits() throws IOException {
 490         checkClosed();
 491         if (bitOffset != 0) {
 492             int offset = bitOffset;
 493             int partialByte = read(); // Sets bitOffset to 0
 494             if (partialByte < 0) {
 495                 // Fix 4465683: When bitOffset is set
 496                 // to something non-zero beyond EOF,
 497                 // we should set that whole byte to
 498                 // zero and write it to stream.
 499                 partialByte = 0;
 500                 bitOffset = 0;
 501             }
 502             else {
 503                 seek(getStreamPosition() - 1);
 504                 partialByte &= -1 << (8 - offset);
 505             }


  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package javax.imageio.stream;
  27 
  28 import java.io.IOException;
  29 import java.io.UTFDataFormatException;
  30 import java.nio.ByteOrder;
  31 
  32 /**
  33  * An abstract class implementing the {@code ImageOutputStream} interface.
  34  * This class is designed to reduce the number of methods that must
  35  * be implemented by subclasses.
  36  *
  37  */
  38 public abstract class ImageOutputStreamImpl
  39     extends ImageInputStreamImpl
  40     implements ImageOutputStream {
  41 
  42     /**
  43      * Constructs an {@code ImageOutputStreamImpl}.
  44      */
  45     public ImageOutputStreamImpl() {
  46     }
  47 
  48     public abstract void write(int b) throws IOException;
  49 
  50     public void write(byte b[]) throws IOException {
  51         write(b, 0, b.length);
  52     }
  53 
  54     public abstract void write(byte b[], int off, int len) throws IOException;
  55 
  56     public void writeBoolean(boolean v) throws IOException {
  57         write(v ? 1 : 0);
  58     }
  59 
  60     public void writeByte(int v) throws IOException {
  61         write(v);
  62     }
  63 


 464             // of the current byte with 0s
 465             else { // EOF
 466                 partialByte = 0;
 467             }
 468 
 469             int shift = 8 - numBits;
 470             int mask = -1 >>> (32 - numBits);
 471             partialByte &= ~(mask << shift);
 472             partialByte |= (bits & mask) << shift;
 473             // bitOffset is always already 0 when we get here.
 474             write(partialByte);
 475             seek(getStreamPosition() - 1);
 476             bitOffset = numBits;
 477         }
 478     }
 479 
 480     /**
 481      * If the bit offset is non-zero, forces the remaining bits
 482      * in the current byte to 0 and advances the stream position
 483      * by one.  This method should be called by subclasses at the
 484      * beginning of the {@code write(int)} and
 485      * {@code write(byte[], int, int)} methods.
 486      *
 487      * @exception IOException if an I/O error occurs.
 488      */
 489     protected final void flushBits() throws IOException {
 490         checkClosed();
 491         if (bitOffset != 0) {
 492             int offset = bitOffset;
 493             int partialByte = read(); // Sets bitOffset to 0
 494             if (partialByte < 0) {
 495                 // Fix 4465683: When bitOffset is set
 496                 // to something non-zero beyond EOF,
 497                 // we should set that whole byte to
 498                 // zero and write it to stream.
 499                 partialByte = 0;
 500                 bitOffset = 0;
 501             }
 502             else {
 503                 seek(getStreamPosition() - 1);
 504                 partialByte &= -1 << (8 - offset);
 505             }
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