Initial revision

From-SVN: r102074

libjava/classpath/javax/imageio/stream/ImageInputStreamImpl.java

@@ -0,0 +1,515 @@
+/* ImageInputStream.java --
+   Copyright (C) 2004  Free Software Foundation, Inc.
+
+This file is part of GNU Classpath.
+
+GNU Classpath is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+GNU Classpath 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 for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU Classpath; see the file COPYING.  If not, write to the
+Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301 USA.
+
+Linking this library statically or dynamically with other modules is
+making a combined work based on this library.  Thus, the terms and
+conditions of the GNU General Public License cover the whole
+combination.
+
+As a special exception, the copyright holders of this library give you
+permission to link this library with independent modules to produce an
+executable, regardless of the license terms of these independent
+modules, and to copy and distribute the resulting executable under
+terms of your choice, provided that you also meet, for each linked
+independent module, the terms and conditions of the license of that
+module.  An independent module is a module which is not derived from
+or based on this library.  If you modify this library, you may extend
+this exception to your version of the library, but you are not
+obligated to do so.  If you do not wish to do so, delete this
+exception statement from your version. */
+
+
+package javax.imageio.stream;
+
+import java.io.DataInputStream;
+import java.io.EOFException;
+import java.io.IOException;
+import java.nio.ByteOrder;
+import java.util.Stack;
+
+/**
+ * @author Michael Koch (konqueror@gmx.de)
+ */
+public abstract class ImageInputStreamImpl implements ImageInputStream
+{
+  private boolean closed;
+  private Stack markStack = new Stack();
+  
+  byte[] buffer = new byte[8];
+  
+  protected int bitOffset;
+  protected ByteOrder byteOrder;
+  protected long flushedPos;
+  protected long streamPos;
+
+  public ImageInputStreamImpl()
+  {
+    // Do nothing here.
+  }
+
+  protected final void checkClosed()
+    throws IOException
+  {
+    if (closed)
+      throw new IOException("stream closed");
+  }
+
+  public void close()
+    throws IOException
+  {
+    checkClosed();
+    closed = true;
+  }
+  
+  protected void finalize()
+    throws Throwable
+  {
+    close();
+  }
+
+  public void flush()
+    throws IOException
+  {
+    flushBefore(getStreamPosition());
+  }
+
+  public void flushBefore(long position)
+    throws IOException
+  {
+    if (position < flushedPos)
+      throw new IndexOutOfBoundsException();
+
+    if (position > streamPos)
+      throw new IndexOutOfBoundsException();
+
+    flushedPos = position;
+  }
+
+  public int getBitOffset()
+    throws IOException
+  {
+    checkClosed();
+    return bitOffset;
+  }
+
+  public ByteOrder getByteOrder()
+  {
+    return byteOrder;
+  }
+
+  public long getFlushedPosition()
+  {
+    return flushedPos;
+  }
+
+  public long getStreamPosition()
+    throws IOException
+  {
+    checkClosed();
+    return streamPos;
+  }
+
+  public boolean isCached()
+  {
+    return false;
+  }
+
+  public boolean isCachedFile()
+  {
+    return false;
+  }
+
+  public boolean isCachedMemory()
+  {
+    return false;
+  }
+
+  public long length()
+  {
+    return -1L;
+  }
+
+  public void mark()
+  {
+    try
+      {
+	markStack.push(new Long(getStreamPosition()));
+      }
+    catch (IOException e)
+      {
+	// Ignored.
+      }
+  }
+
+  public abstract int read()
+    throws IOException;
+
+  public int read(byte[] data)
+    throws IOException
+  {
+    return read(data, 0, data.length);
+  }
+
+  public abstract int read(byte[] data, int offset, int len)
+    throws IOException;
+
+  public int readBit()
+    throws IOException
+  {
+    checkClosed();
+
+    // Calc new bit offset here, readByte resets it.
+    int newOffset = (bitOffset + 1) & 0x7;
+
+    byte data = readByte();
+    
+    if (bitOffset != 0)
+      {
+	seek(getStreamPosition() - 1);
+	data = (byte) (data >> (8 - newOffset));
+      }
+
+    bitOffset = newOffset;
+    return data & 0x1;
+  }
+
+  public long readBits(int numBits)
+    throws IOException
+  {
+    checkClosed();
+
+    if (numBits < 0 || numBits > 64)
+      throw new IllegalArgumentException();
+
+    if (numBits == 0)
+      return 0L;
+
+    long bits = 0L;
+    
+    for (int i = 0; i < numBits; i++)
+      {
+	bits <<= 1;
+	bits |= readBit();
+      }
+
+    return bits;
+  }
+
+  public boolean readBoolean()
+    throws IOException
+  {
+    byte data = readByte();
+    return data != 0;
+  }
+
+  public byte readByte()
+    throws IOException
+  {
+    int data = read();
+
+    if (data == -1)
+      throw new EOFException();
+
+    return (byte) data;
+  }
+
+  public void readBytes(IIOByteBuffer buffer, int len)
+    throws IOException
+  {
+    int result = read(buffer.getData(), buffer.getOffset(), len);
+    
+    if (result == -1 || result < len)
+      throw new EOFException();
+
+    buffer.setLength(len);
+  }
+
+  public char readChar()
+    throws IOException
+  {
+    return (char) readShort();
+  }
+
+  public double readDouble()
+    throws IOException
+  {
+    return (double) readLong();
+  }
+
+  public float readFloat()
+    throws IOException
+  {
+    return (float) readInt();
+  }
+
+  public void readFully(byte[] data)
+    throws IOException
+  {
+    readFully(data, 0, data.length);
+  }
+
+  public void readFully(byte[] data, int offset, int len)
+    throws IOException
+  {
+    for (int i = 0; i < len; ++i)
+      data[offset + i] = readByte();
+  }
+
+  public void readFully(char[] data, int offset, int len)
+    throws IOException
+  {
+    for (int i = 0; i < len; ++i)
+      data[offset + i] = readChar();
+  }
+
+  public void readFully(double[] data, int offset, int len)
+    throws IOException
+  {
+    for (int i = 0; i < len; ++i)
+      data[offset + i] = readDouble();
+  }
+
+  public void readFully(float[] data, int offset, int len)
+    throws IOException
+  {
+    for (int i = 0; i < len; ++i)
+      data[offset + i] = readFloat();
+  }
+
+  public void readFully(int[] data, int offset, int len)
+    throws IOException
+  {
+    for (int i = 0; i < len; ++i)
+      data[offset + i] = readInt();
+  }
+
+  public void readFully(long[] data, int offset, int len)
+    throws IOException
+  {
+    for (int i = 0; i < len; ++i)
+      data[offset + i] = readLong();
+  }
+
+  public void readFully(short[] data, int offset, int len)
+    throws IOException
+  {
+    for (int i = 0; i < len; ++i)
+      data[offset + i] = readShort();
+  }
+
+  public int readInt()
+    throws IOException
+  {
+    int result = read(buffer, 0, 4);
+
+    if (result == -1)
+      throw new EOFException();
+    
+    if (getByteOrder() == ByteOrder.LITTLE_ENDIAN)
+      {
+	return ((buffer[0] & 0xff)
+		+ (buffer[1] << 8)
+		+ (buffer[2] << 16)
+		+ (buffer[3] << 24));
+      }
+
+    return ((buffer[4] << 24)
+	    + (buffer[3] << 16)
+	    + (buffer[2] << 8)
+	    + (buffer[1] & 0xff));
+  }
+
+  public String readLine()
+    throws IOException
+  {
+    checkClosed();
+
+    int c = -1;
+    boolean eol = false;
+    StringBuffer buffer = new StringBuffer();
+
+    while (!eol && (c = read()) != -1)
+      {
+	switch(c)
+	  {
+	  case '\r':
+	    // Consume following \n'
+	    long oldPosition = getStreamPosition();
+	    if (read() != '\n')
+	       seek(oldPosition);
+	  case '\n':
+	    eol = true;
+	    break;
+	  default:
+	    buffer.append((char) c);
+	    break;
+	  }
+      }
+
+    if (c == -1 && buffer.length() == 0)
+      return null;
+
+    return buffer.toString();
+  }
+
+  public long readLong()
+    throws IOException
+  {
+    int result = read(buffer, 0, 8);
+
+    if (result == -1)
+      throw new EOFException();
+    
+    if (getByteOrder() == ByteOrder.LITTLE_ENDIAN)
+      {
+        return ((buffer[0] & 0xff)
+                + (((buffer[1] & 0xff)) << 8)
+                + (((buffer[2] & 0xff)) << 16)
+                + (((buffer[3] & 0xffL)) << 24)
+                + (((buffer[4] & 0xffL)) << 32)
+                + (((buffer[5] & 0xffL)) << 40)
+                + (((buffer[6] & 0xffL)) << 48)
+                + (((long) buffer[7]) << 56));
+      }
+
+    return ((((long) buffer[7]) << 56)
+            + ((buffer[6] & 0xffL) << 48)
+            + ((buffer[5] & 0xffL) << 40)
+            + ((buffer[4] & 0xffL) << 32)
+            + ((buffer[3] & 0xffL) << 24)
+            + ((buffer[2] & 0xff) << 16)
+            + ((buffer[1] & 0xff) << 8)
+            + (buffer[0] & 0xff));
+  }
+
+  public short readShort()
+    throws IOException
+  {
+    int result = read(buffer, 0, 2);
+
+    if (result == -1)
+      throw new EOFException();
+    
+    if (getByteOrder() == ByteOrder.LITTLE_ENDIAN)
+      {
+	return (short) ((buffer[0] & 0xff)
+			+ (buffer[1] << 8));
+      }
+
+    return (short) ((buffer[0] << 8)
+		    + (buffer[1] & 0xff));
+  }
+
+  public int readUnsignedByte()
+    throws IOException
+  {
+    return readByte() & 0xff;
+  }
+
+  public long readUnsignedInt()
+    throws IOException
+  {
+    return readInt() & 0xffffffff;
+  }
+
+  public int readUnsignedShort()
+    throws IOException
+  {
+    return readShort() & 0xffff;
+  }
+
+  public String readUTF()
+    throws IOException
+  {
+    checkClosed();
+
+    String data;
+    ByteOrder old = getByteOrder();
+    setByteOrder(ByteOrder.BIG_ENDIAN); // Strings are always big endian.
+
+    try
+      {
+	data = DataInputStream.readUTF(this);
+      }
+    finally
+      {
+	setByteOrder(old);
+      }
+    
+    return data;
+  }
+
+  public void reset()
+    throws IOException
+  {
+    checkClosed();
+    
+    long mark = ((Long) markStack.pop()).longValue();
+    seek(mark);
+  }
+
+  public void seek(long position)
+    throws IOException
+  {
+    checkClosed();
+
+    if (position < getFlushedPosition())
+      throw new IndexOutOfBoundsException("position < flushed position");
+
+    streamPos = position;
+    bitOffset = 0;
+  }
+
+  public void setBitOffset (int bitOffset)
+    throws IOException
+  {
+    checkClosed();
+    
+    if (bitOffset < 0 || bitOffset > 7)
+      throw new IllegalArgumentException();
+
+    this.bitOffset = bitOffset;
+  }
+
+  public void setByteOrder(ByteOrder byteOrder)
+  {
+    this.byteOrder = byteOrder;
+  }
+
+  public int skipBytes(int num)
+    throws IOException
+  {
+    checkClosed();
+    
+    seek(getStreamPosition() + num);
+    bitOffset = 0;
+    return num;
+  }
+
+  public long skipBytes(long num)
+    throws IOException
+  {
+    checkClosed();
+    
+    seek(getStreamPosition() + num);
+    bitOffset = 0;
+    return num;
+  }
+}