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Diffstat (limited to 'gcc-4.4.3/libjava/classpath/gnu/CORBA/CDR/LittleEndianInputStream.java')
| -rw-r--r-- | gcc-4.4.3/libjava/classpath/gnu/CORBA/CDR/LittleEndianInputStream.java | 634 |
1 files changed, 634 insertions, 0 deletions
diff --git a/gcc-4.4.3/libjava/classpath/gnu/CORBA/CDR/LittleEndianInputStream.java b/gcc-4.4.3/libjava/classpath/gnu/CORBA/CDR/LittleEndianInputStream.java new file mode 100644 index 000000000..93d18fb11 --- /dev/null +++ b/gcc-4.4.3/libjava/classpath/gnu/CORBA/CDR/LittleEndianInputStream.java @@ -0,0 +1,634 @@ +/* LittleEndianInputStream.java -- + Copyright (C) 1998, 1999, 2000, 2001, 2003, 2005 Free Software Foundation + +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 gnu.CORBA.CDR; + +import gnu.java.lang.CPStringBuilder; + +import java.io.EOFException; +import java.io.FilterInputStream; +import java.io.IOException; +import java.io.InputStream; +import java.io.PushbackInputStream; + +/** + * This class reads data in the Little Endian format. It reuses + * code from GNU Classpath DataInputStream. + * + * @author Audrius Meskauskas (AudriusA@Bioinformatics.org) + * @author Warren Levy (warrenl@cygnus.com) + * @author Aaron M. Renn (arenn@urbanophile.com) + */ +public class LittleEndianInputStream + extends FilterInputStream + implements AbstractDataInput +{ + // Byte buffer, used to make primitive read calls more efficient. + byte[] buf = new byte[ 8 ]; + + /** + * This constructor initializes a new <code>DataInputStream</code> + * to read from the specified subordinate stream. + * + * @param in The subordinate <code>InputStream</code> to read from + */ + public LittleEndianInputStream(InputStream in) + { + super(in); + } + + /** + * This method reads bytes from the underlying stream into the specified + * byte array buffer. It will attempt to fill the buffer completely, but + * may return a short count if there is insufficient data remaining to be + * read to fill the buffer. + * + * @param b The buffer into which bytes will be read. + * + * @return The actual number of bytes read, or -1 if end of stream reached + * before reading any bytes. + * + * @exception IOException If an error occurs. + */ + public int read(byte[] b) + throws IOException + { + return in.read(b, 0, b.length); + } + + /** + * This method reads bytes from the underlying stream into the specified + * byte array buffer. It will attempt to read <code>len</code> bytes and + * will start storing them at position <code>off</code> into the buffer. + * This method can return a short count if there is insufficient data + * remaining to be read to complete the desired read length. + * + * @param b The buffer into which bytes will be read. + * @param off The offset into the buffer to start storing bytes. + * @param len The requested number of bytes to read. + * + * @return The actual number of bytes read, or -1 if end of stream reached + * before reading any bytes. + * + * @exception IOException If an error occurs. + */ + public int read(byte[] b, int off, int len) + throws IOException + { + return in.read(b, off, len); + } + + /** + * This method reads a Java boolean value from an input stream. It does + * so by reading a single byte of data. If that byte is zero, then the + * value returned is <code>false</code>. If the byte is non-zero, then + * the value returned is <code>true</code>. + * <p> + * This method can read a <code>boolean</code> written by an object + * implementing the <code>writeBoolean()</code> method in the + * <code>DataOutput</code> interface. + * + * @return The <code>boolean</code> value read + * + * @exception EOFException If end of file is reached before reading + * the boolean + * @exception IOException If any other error occurs + * + * @see DataOutput#writeBoolean + */ + public boolean readBoolean() + throws IOException + { + return convertToBoolean(in.read()); + } + + /** + * This method reads a Java byte value from an input stream. The value + * is in the range of -128 to 127. + * <p> + * This method can read a <code>byte</code> written by an object + * implementing the <code>writeByte()</code> method in the + * <code>DataOutput</code> interface. + * + * @return The <code>byte</code> value read + * + * @exception EOFException If end of file is reached before reading the byte + * @exception IOException If any other error occurs + * + * @see DataOutput#writeByte + */ + public byte readByte() + throws IOException + { + return convertToByte(in.read()); + } + + /** + * This method reads a Java <code>char</code> value from an input stream. + * It operates by reading two bytes from the stream and converting them to + * a single 16-bit Java <code>char</code>. The two bytes are stored most + * significant byte first (i.e., "big endian") regardless of the native + * host byte ordering. + * <p> + * As an example, if <code>byte1</code> and <code>byte2</code> + * represent the first and second byte read from the stream + * respectively, they will be transformed to a <code>char</code> in + * the following manner: + * <p> + * <code>(char)(((byte1 & 0xFF) << 8) | (byte2 & 0xFF)</code> + * <p> + * This method can read a <code>char</code> written by an object + * implementing the <code>writeChar()</code> method in the + * <code>DataOutput</code> interface. + * + * @return The <code>char</code> value read + * + * @exception EOFException If end of file is reached before reading the char + * @exception IOException If any other error occurs + * + * @see DataOutput#writeChar + */ + public char readChar() + throws IOException + { + readFully(buf, 0, 2); + return convertToChar(buf); + } + + /** + * This method reads a Java double value from an input stream. It operates + * by first reading a <code>long</code> value from the stream by calling the + * <code>readLong()</code> method in this interface, then converts + * that <code>long</code> to a <code>double</code> using the + * <code>longBitsToDouble</code> method in the class + * <code>java.lang.Double</code> + * <p> + * This method can read a <code>double</code> written by an object + * implementing the <code>writeDouble()</code> method in the + * <code>DataOutput</code> interface. + * + * @return The <code>double</code> value read + * + * @exception EOFException If end of file is reached before reading + * the double + * @exception IOException If any other error occurs + * + * @see DataOutput#writeDouble + * @see java.lang.Double#longBitsToDouble + */ + public double readDouble() + throws IOException + { + return Double.longBitsToDouble(readLong()); + } + + /** + * This method reads a Java float value from an input stream. It + * operates by first reading an <code>int</code> value from the + * stream by calling the <code>readInt()</code> method in this + * interface, then converts that <code>int</code> to a + * <code>float</code> using the <code>intBitsToFloat</code> method + * in the class <code>java.lang.Float</code> + * <p> + * This method can read a <code>float</code> written by an object + * implementing the <code>writeFloat()</code> method in the + * <code>DataOutput</code> interface. + * + * @return The <code>float</code> value read + * + * @exception EOFException If end of file is reached before reading the float + * @exception IOException If any other error occurs + * + * @see DataOutput#writeFloat + * @see java.lang.Float#intBitsToFloat + */ + public float readFloat() + throws IOException + { + return Float.intBitsToFloat(readInt()); + } + + /** + * This method reads raw bytes into the passed array until the array is + * full. Note that this method blocks until the data is available and + * throws an exception if there is not enough data left in the stream to + * fill the buffer. Note also that zero length buffers are permitted. + * In this case, the method will return immediately without reading any + * bytes from the stream. + * + * @param b The buffer into which to read the data + * + * @exception EOFException If end of file is reached before filling the + * buffer + * @exception IOException If any other error occurs + */ + public void readFully(byte[] b) + throws IOException + { + readFully(b, 0, b.length); + } + + /** + * This method reads raw bytes into the passed array <code>buf</code> + * starting + * <code>offset</code> bytes into the buffer. The number of bytes read + * will be + * exactly <code>len</code>. Note that this method blocks until the data is + * available and throws an exception if there is not enough data left in + * the stream to read <code>len</code> bytes. Note also that zero length + * buffers are permitted. In this case, the method will return immediately + * without reading any bytes from the stream. + * + * @param buf The buffer into which to read the data + * @param offset The offset into the buffer to start storing data + * @param len The number of bytes to read into the buffer + * + * @exception EOFException If end of file is reached before filling the + * buffer + * @exception IOException If any other error occurs + */ + public void readFully(byte[] buf, int offset, int len) + throws IOException + { + if (len < 0) + throw new IndexOutOfBoundsException("Negative length: " + len); + + while (len > 0) + { + // in.read will block until some data is available. + int numread = in.read(buf, offset, len); + if (numread < 0) + throw new EOFException(); + len -= numread; + offset += numread; + } + } + + /** + * This method reads a Java <code>int</code> value from an input stream + * It operates by reading four bytes from the stream and converting them to + * a single Java <code>int</code>. The bytes are stored most + * significant byte first (i.e., "big endian") regardless of the native + * host byte ordering. + * <p> + * As an example, if <code>byte1</code> through <code>byte4</code> represent + * the first four bytes read from the stream, they will be + * transformed to an <code>int</code> in the following manner: + * <p> + * <code>(int)(((byte1 & 0xFF) << 24) + ((byte2 & 0xFF) << 16) + + * ((byte3 & 0xFF)<< 8) + (byte4 & 0xFF)))</code> + * <p> + * The value returned is in the range of -2147483648 to 2147483647. + * <p> + * This method can read an <code>int</code> written by an object + * implementing the <code>writeInt()</code> method in the + * <code>DataOutput</code> interface. + * + * @return The <code>int</code> value read + * + * @exception EOFException If end of file is reached before reading the int + * @exception IOException If any other error occurs + * + * @see DataOutput#writeInt + */ + public int readInt() + throws IOException + { + readFully(buf, 0, 4); + return convertToInt(buf); + } + + /** + * This method reads the next line of text data from an input + * stream. It operates by reading bytes and converting those bytes + * to <code>char</code> values by treating the byte read as the low + * eight bits of the <code>char</code> and using 0 as the high eight + * bits. Because of this, it does not support the full 16-bit + * Unicode character set. + * <p> + * The reading of bytes ends when either the end of file or a line + * terminator is encountered. The bytes read are then returned as a + * <code>String</code> A line terminator is a byte sequence + * consisting of either <code>\r</code>, <code>\n</code> or + * <code>\r\n</code>. These termination charaters are discarded and + * are not returned as part of the string. + * <p> + * This method can read data that was written by an object implementing the + * <code>writeLine()</code> method in <code>DataOutput</code>. + * + * @return The line read as a <code>String</code> + * + * @exception IOException If an error occurs + * + * @see DataOutput + * + * @deprecated + */ + public String readLine() + throws IOException + { + CPStringBuilder strb = new CPStringBuilder(); + + while (true) + { + int c = in.read(); + if (c == -1) // got an EOF + return strb.length() > 0 ? strb.toString() : null; + if (c == '\r') + { + int next_c = in.read(); + if (next_c != '\n' && next_c != -1) + { + if (!(in instanceof PushbackInputStream)) + in = new PushbackInputStream(in); + ((PushbackInputStream) in).unread(next_c); + } + break; + } + if (c == '\n') + break; + strb.append((char) c); + } + + return strb.length() > 0 ? strb.toString() : ""; + } + + /** + * This method reads a Java <code>long</code> value from an input stream + * It operates by reading eight bytes from the stream and converting them to + * a single Java <code>long</code>. The bytes are stored most + * significant byte first (i.e., "big endian") regardless of the native + * host byte ordering. + * <p> + * As an example, if <code>byte1</code> through <code>byte8</code> represent + * the first eight bytes read from the stream, they will be + * transformed to an <code>long</code> in the following manner: + * <p> + * <code>(long)(((byte1 & 0xFF) << 56) + ((byte2 & 0xFF) << 48) + + * ((byte3 & 0xFF) << 40) + ((byte4 & 0xFF) << 32) + + * ((byte5 & 0xFF) << 24) + ((byte6 & 0xFF) << 16) + + * ((byte7 & 0xFF) << 8) + (byte8 & 0xFF))) + * </code> + * <p> + * The value returned is in the range of -9223372036854775808 to + * 9223372036854775807. + * <p> + * This method can read an <code>long</code> written by an object + * implementing the <code>writeLong()</code> method in the + * <code>DataOutput</code> interface. + * + * @return The <code>long</code> value read + * + * @exception EOFException If end of file is reached before reading the long + * @exception IOException If any other error occurs + * + * @see DataOutput#writeLong + */ + public long readLong() + throws IOException + { + readFully(buf, 0, 8); + return convertToLong(buf); + } + + /** + * This method reads a signed 16-bit value into a Java in from the + * stream. It operates by reading two bytes from the stream and + * converting them to a single 16-bit Java <code>short</code>. The + * two bytes are stored most significant byte first (i.e., "big + * endian") regardless of the native host byte ordering. + * <p> + * As an example, if <code>byte1</code> and <code>byte2</code> + * represent the first and second byte read from the stream + * respectively, they will be transformed to a <code>short</code>. in + * the following manner: + * <p> + * <code>(short)(((byte1 & 0xFF) << 8) | (byte2 & 0xFF))</code> + * <p> + * The value returned is in the range of -32768 to 32767. + * <p> + * This method can read a <code>short</code> written by an object + * implementing the <code>writeShort()</code> method in the + * <code>DataOutput</code> interface. + * + * @return The <code>short</code> value read + * + * @exception EOFException If end of file is reached before reading the value + * @exception IOException If any other error occurs + * + * @see DataOutput#writeShort + */ + public short readShort() + throws IOException + { + readFully(buf, 0, 2); + return convertToShort(buf); + } + + /** + * This method reads 8 unsigned bits into a Java <code>int</code> + * value from the stream. The value returned is in the range of 0 to + * 255. + * <p> + * This method can read an unsigned byte written by an object + * implementing the <code>writeUnsignedByte()</code> method in the + * <code>DataOutput</code> interface. + * + * @return The unsigned bytes value read as a Java <code>int</code>. + * + * @exception EOFException If end of file is reached before reading the value + * @exception IOException If any other error occurs + * + * @see DataOutput#writeByte + */ + public int readUnsignedByte() + throws IOException + { + return convertToUnsignedByte(in.read()); + } + + /** + * This method reads 16 unsigned bits into a Java int value from the stream. + * It operates by reading two bytes from the stream and converting them to + * a single Java <code>int</code> The two bytes are stored most + * significant byte first (i.e., "big endian") regardless of the native + * host byte ordering. + * <p> + * As an example, if <code>byte1</code> and <code>byte2</code> + * represent the first and second byte read from the stream + * respectively, they will be transformed to an <code>int</code> in + * the following manner: + * <p> + * <code>(int)(((byte1 & 0xFF) << 8) + (byte2 & 0xFF))</code> + * <p> + * The value returned is in the range of 0 to 65535. + * <p> + * This method can read an unsigned short written by an object + * implementing the <code>writeUnsignedShort()</code> method in the + * <code>DataOutput</code> interface. + * + * @return The unsigned short value read as a Java <code>int</code> + * + * @exception EOFException If end of file is reached before reading the value + * @exception IOException If any other error occurs + * + * @see DataOutput#writeShort + */ + public int readUnsignedShort() + throws IOException + { + readFully(buf, 0, 2); + return convertToUnsignedShort(buf); + } + + /** + * This method attempts to skip and discard the specified number of bytes + * in the input stream. It may actually skip fewer bytes than requested. + * This method will not skip any bytes if passed a negative number of bytes + * to skip. + * + * @param n The requested number of bytes to skip. + * + * @return The requested number of bytes to skip. + * + * @exception IOException If an error occurs. + * @specnote The JDK docs claim that this returns the number of bytes + * actually skipped. The JCL claims that this method can throw an + * EOFException. Neither of these appear to be true in the JDK 1.3's + * implementation. This tries to implement the actual JDK behaviour. + */ + public int skipBytes(int n) + throws IOException + { + if (n <= 0) + return 0; + try + { + return (int) in.skip(n); + } + catch (EOFException x) + { + // do nothing. + } + return n; + } + + protected boolean convertToBoolean(int b) + throws EOFException + { + if (b < 0) + throw new EOFException(); + + return (b != 0); + } + + protected byte convertToByte(int i) + throws EOFException + { + if (i < 0) + throw new EOFException(); + + return (byte) i; + } + + protected int convertToUnsignedByte(int i) + throws EOFException + { + if (i < 0) + throw new EOFException(); + + return (i & 0xFF); + } + + /** + * Less significant byte first. + */ + protected char convertToChar(byte[] buf) + { + return (char) ((buf [ 1 ] << 8) | (buf [ 0 ] & 0xff)); + } + + /** + * Less significant byte first. + */ + protected short convertToShort(byte[] buf) + { + return (short) ((buf [ 1 ] << 8) | (buf [ 0 ] & 0xff)); + } + + /** + * Less significant byte first. + */ + protected int convertToUnsignedShort(byte[] buf) + { + return (((buf [ 1 ] & 0xff) << 8) | (buf [ 0 ] & 0xff)); + } + + /** + * Less significant byte first. + */ + protected int convertToInt(byte[] buf) + { + return (((buf [ 3 ] & 0xff) << 24) | ((buf [ 2 ] & 0xff) << 16) | + ((buf [ 1 ] & 0xff) << 8) | (buf [ 0 ] & 0xff)); + } + + /** + * Less significant byte first. + */ + protected long convertToLong(byte[] buf) + { + return (((long) (buf [ 7 ] & 0xff) << 56) | + ((long) (buf [ 6 ] & 0xff) << 48) | + ((long) (buf [ 5 ] & 0xff) << 40) | + ((long) (buf [ 4 ] & 0xff) << 32) | + ((long) (buf [ 3 ] & 0xff) << 24) | + ((long) (buf [ 2 ] & 0xff) << 16) | + ((long) (buf [ 1 ] & 0xff) << 8) | ((long) (buf [ 0 ] & 0xff))); + } + + /** + * This should never be called. + * + * @throws InternalError, always. + */ + public String readUTF() + { + throw new InternalError(); + } +} |