/*
* Player Java Client 3 - XdrDecodingStream.java
* Copyright (C) 2002-2006 Radu Bogdan Rusu, Maxim Batalin
*
* This program 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 of the License, or
* (at your option) any later version.
*
* This program 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 this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* $Id$
*
*/
/*
* Copyright (c) 1999, 2000
* Lehrstuhl fuer Prozessleittechnik (PLT), RWTH Aachen
* D-52064 Aachen, Germany.
* All rights reserved.
*
* This library is free software; you can redistribute it and/or modify
* it under the terms of the GNU Library General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This library 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 Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this program (see the file COPYING.LIB for more
* details); if not, write to the Free Software Foundation, Inc.,
* 675 Mass Ave, Cambridge, MA 02139, USA.
*/
package javaclient3.xdr;
import java.io.IOException;
import java.net.InetAddress;
/**
* Defines the abstract base class for all decoding XDR streams. A decoding
* XDR stream returns data in the form of Java data types which it reads
* from a data source (for instance, network or memory buffer) in the
* platform-independent XDR format.
*
* <p>Derived classes need to implement the {@link #xdrDecodeInt()},
* {@link #xdrDecodeOpaque(int)} and
* {@link #xdrDecodeOpaque(byte[], int, int)} methods to make this complete
* mess workable.
*
* @version $Revision$ $Date$ $State$ $Locker$
* @author Harald Albrecht
*/
public abstract class XdrDecodingStream {
/**
* Returns the Internet address of the sender of the current XDR data.
* This method should only be called after {@link #beginDecoding}, otherwise
* it might return stale information.
*
* @return InetAddress of the sender of the current XDR data.
*/
public abstract InetAddress getSenderAddress();
/**
* Returns the port number of the sender of the current XDR data.
* This method should only be called after {@link #beginDecoding}, otherwise
* it might return stale information.
*
* @return Port number of the sender of the current XDR data.
*/
public abstract int getSenderPort();
/**
* Initiates decoding of the next XDR record. This typically involves
* filling the internal buffer with the next datagram from the network, or
* reading the next chunk of data from a stream-oriented connection. In
* case of memory-based communication this might involve waiting for
* some other process to fill the buffer and signal availability of new
* XDR data.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
*/
public abstract void beginDecoding()
throws OncRpcException, IOException;
/**
* End decoding of the current XDR record. The general contract of
* <code>endDecoding</code> is that calling it is an indication that
* the current record is no more interesting to the caller and any
* allocated data for this record can be freed.
*
* <p>The <code>endDecoding</code> method of <code>XdrDecodingStream</code>
* does nothing.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
*/
public void endDecoding()
throws OncRpcException, IOException {
}
/**
* Closes this decoding XDR stream and releases any system resources
* associated with this stream. The general contract of <code>close</code>
* is that it closes the decoding XDR stream. A closed XDR stream cannot
* perform decoding operations and cannot be reopened.
*
* <p>The <code>close</code> method of <code>XdrDecodingStream</code>
* does nothing.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
*/
public void close()
throws OncRpcException, IOException {
}
/**
* Decodes (aka "deserializes") a "XDR int" value received from a
* XDR stream. A XDR int is 32 bits wide -- the same width Java's "int"
* data type has. This method is one of the basic methods all other
* methods can rely on. Because it's so basic, derived classes have to
* implement it.
*
* @return The decoded int value.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
*/
public abstract int xdrDecodeInt()
throws OncRpcException, IOException;
/**
* Decodes (aka "deserializes") an opaque value, which is nothing more
* than a series of octets (or 8 bits wide bytes). Because the length
* of the opaque value is given, we don't need to retrieve it from the
* XDR stream.
*
* <p>Note that this is a basic abstract method, which needs to be
* implemented in derived classes.
*
* @param length Length of opaque data to decode.
*
* @return Opaque data as a byte vector.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
*/
public abstract byte [] xdrDecodeOpaque(int length)
throws OncRpcException, IOException;
/**
* Decodes (aka "deserializes") a XDR opaque value, which is represented
* by a vector of byte values, and starts at <code>offset</code> with a
* length of <code>length</code>. Only the opaque value is decoded, so the
* caller has to know how long the opaque value will be. The decoded data
* is always padded to be a multiple of four (because that's what the
* sender does).
*
* <p>Derived classes must ensure that the proper semantic is maintained.
*
* @param opaque Byte vector which will receive the decoded opaque value.
* @param offset Start offset in the byte vector.
* @param length the number of bytes to decode.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
* @throws IndexOutOfBoundsException if the given <code>opaque</code>
* byte vector isn't large enough to receive the result.
*/
public abstract void xdrDecodeOpaque(byte [] opaque, int offset, int length)
throws OncRpcException, IOException;
/**
* Decodes (aka "deserializes") a XDR opaque value, which is represented
* by a vector of byte values. Only the opaque value is decoded, so the
* caller has to know how long the opaque value will be. The decoded data
* is always padded to be a multiple of four (because that's what the
* sender does).
*
* @param opaque Byte vector which will receive the decoded opaque value.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
*/
public final void xdrDecodeOpaque(byte [] opaque)
throws OncRpcException, IOException {
xdrDecodeOpaque(opaque, 0, opaque.length);
}
/**
* Decodes (aka "deserializes") a XDR opaque value, which is represented
* by a vector of byte values. The length of the opaque value to decode
* is pulled off of the XDR stream, so the caller does not need to know
* the exact length in advance. The decoded data is always padded to be
* a multiple of four (because that's what the sender does).
*
* @return The byte vector containing the decoded data.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
*/
public final byte [] xdrDecodeDynamicOpaque()
throws OncRpcException, IOException {
int length = xdrDecodeInt();
byte [] opaque = new byte[length];
if ( length != 0 ) {
xdrDecodeOpaque(opaque);
}
return opaque;
}
/**
* Decodes (aka "deserializes") a vector of bytes, which is nothing more
* than a series of octets (or 8 bits wide bytes), each packed into its
* very own 4 bytes (XDR int). Byte vectors are decoded together with a
* preceeding length value. This way the receiver doesn't need to know
* the length of the vector in advance.
*
* @return The byte vector containing the decoded data.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
*/
public final byte [] xdrDecodeByteVector()
throws OncRpcException, IOException {
int length = xdrDecodeInt();
if ( length > 0 ) {
byte [] bytes = new byte[length];
for ( int i = 0; i < length; ++i ) {
bytes[i] = (byte) xdrDecodeInt();
}
return bytes;
} else {
return new byte[0];
}
}
/**
* Decodes (aka "deserializes") a vector of bytes, which is nothing more
* than a series of octets (or 8 bits wide bytes), each packed into its
* very own 4 bytes (XDR int).
*
* @param length of vector to read.
*
* @return The byte vector containing the decoded data.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
*/
public final byte [] xdrDecodeByteFixedVector(int length)
throws OncRpcException, IOException {
if ( length > 0 ) {
byte [] bytes = new byte[length];
for ( int i = 0; i < length; ++i ) {
bytes[i] = (byte) xdrDecodeInt();
}
return bytes;
} else {
return new byte[0];
}
}
/**
* Decodes (aka "deserializes") a byte read from this XDR stream.
*
* @return Decoded byte value.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
*/
public final byte xdrDecodeByte()
throws OncRpcException, IOException {
return (byte) xdrDecodeInt();
}
/**
* Decodes (aka "deserializes") a short (which is a 16 bit quantity)
* read from this XDR stream.
*
* @return Decoded short value.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
*/
public final short xdrDecodeShort()
throws OncRpcException, IOException {
return (short) xdrDecodeInt();
}
/**
* Decodes (aka "deserializes") a long (which is called a "hyper" in XDR
* babble and is 64 bits wide) read from a XDR stream.
*
* @return Decoded long value.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
*/
public final long xdrDecodeLong()
throws OncRpcException, IOException {
//
// Similiar to xdrEncodeLong: just read in two ints in network order.
//
return (((long) xdrDecodeInt()) << 32) +
(((long) xdrDecodeInt()) & 0x00000000FFFFFFFFl);
}
/**
* Decodes (aka "deserializes") a float (which is a 32 bits wide floating
* point entity) read from a XDR stream.
*
* @return Decoded float value.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
*/
public final float xdrDecodeFloat()
throws OncRpcException, IOException {
return Float.intBitsToFloat(xdrDecodeInt());
}
/**
* Decodes (aka "deserializes") a double (which is a 64 bits wide floating
* point entity) read from a XDR stream.
*
* @return Decoded double value.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
*/
public final double xdrDecodeDouble()
throws OncRpcException, IOException {
return Double.longBitsToDouble(xdrDecodeLong());
}
/**
* Decodes (aka "deserializes") a boolean read from a XDR stream.
*
* @return Decoded boolean value.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
*/
public final boolean xdrDecodeBoolean()
throws OncRpcException, IOException {
return xdrDecodeInt() != 0 ? true : false;
}
/**
* Decodes (aka "deserializes") a string read from a XDR stream.
* If a character encoding has been set for this stream, then this
* will be used for conversion.
*
* @return Decoded String value.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
*/
public final String xdrDecodeString()
throws OncRpcException, IOException {
int length = xdrDecodeInt();
if ( length > 0 ) {
byte [] bytes = new byte[length];
xdrDecodeOpaque(bytes, 0, length);
return (characterEncoding != null) ?
new String(bytes, characterEncoding) :
new String(bytes);
} else {
return new String();
}
}
/**
* Decodes (aka "deserializes") a vector of short integers read from a
* XDR stream.
*
* @return Decoded vector of short integers.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
*/
public final short [] xdrDecodeShortVector()
throws OncRpcException, IOException {
int length = xdrDecodeInt();
short [] value = new short[length];
for ( int i = 0; i < length; ++i ) {
value[i] = xdrDecodeShort();
}
return value;
}
/**
* Decodes (aka "deserializes") a vector of short integers read from a
* XDR stream.
*
* @param length of vector to read.
*
* @return Decoded vector of short integers.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
*/
public final short [] xdrDecodeShortFixedVector(int length)
throws OncRpcException, IOException {
short [] value = new short[length];
for ( int i = 0; i < length; ++i ) {
value[i] = xdrDecodeShort();
}
return value;
}
/**
* Decodes (aka "deserializes") a vector of ints read from a XDR stream.
*
* @return Decoded int vector.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
*/
public final int [] xdrDecodeIntVector()
throws OncRpcException, IOException {
int length = xdrDecodeInt();
int [] value = new int[length];
for ( int i = 0; i < length; ++i ) {
value[i] = xdrDecodeInt();
}
return value;
}
/**
* Decodes (aka "deserializes") a vector of ints read from a XDR stream.
*
* @param length of vector to read.
*
* @return Decoded int vector.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
*/
public final int [] xdrDecodeIntFixedVector(int length)
throws OncRpcException, IOException {
int [] value = new int[length];
for ( int i = 0; i < length; ++i ) {
value[i] = xdrDecodeInt();
}
return value;
}
/**
* Decodes (aka "deserializes") a vector of longs read from a XDR stream.
*
* @return Decoded long vector.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
*/
public final long [] xdrDecodeLongVector()
throws OncRpcException, IOException {
int length = xdrDecodeInt();
long [] value = new long[length];
for ( int i = 0; i < length; ++i ) {
value[i] = xdrDecodeLong();
}
return value;
}
/**
* Decodes (aka "deserializes") a vector of longs read from a XDR stream.
*
* @param length of vector to read.
*
* @return Decoded long vector.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
*/
public final long [] xdrDecodeLongFixedVector(int length)
throws OncRpcException, IOException {
long [] value = new long[length];
for ( int i = 0; i < length; ++i ) {
value[i] = xdrDecodeLong();
}
return value;
}
/**
* Decodes (aka "deserializes") a vector of floats read from a XDR stream.
*
* @return Decoded float vector.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
*/
public final float [] xdrDecodeFloatVector()
throws OncRpcException, IOException {
int length = xdrDecodeInt();
float [] value = new float[length];
for ( int i = 0; i < length; ++i ) {
value[i] = xdrDecodeFloat();
}
return value;
}
/**
* Decodes (aka "deserializes") a vector of floats read from a XDR stream.
*
* @param length of vector to read.
*
* @return Decoded float vector.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
*/
public final float [] xdrDecodeFloatFixedVector(int length)
throws OncRpcException, IOException {
float [] value = new float[length];
for ( int i = 0; i < length; ++i ) {
value[i] = xdrDecodeFloat();
}
return value;
}
/**
* Decodes (aka "deserializes") a vector of doubles read from a XDR stream.
*
* @return Decoded double vector.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
*/
public final double [] xdrDecodeDoubleVector()
throws OncRpcException, IOException {
int length = xdrDecodeInt();
double [] value = new double[length];
for ( int i = 0; i < length; ++i ) {
value[i] = xdrDecodeDouble();
}
return value;
}
/**
* Decodes (aka "deserializes") a vector of doubles read from a XDR stream.
*
* @param length of vector to read.
*
* @return Decoded double vector.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
*/
public final double [] xdrDecodeDoubleFixedVector(int length)
throws OncRpcException, IOException {
double [] value = new double[length];
for ( int i = 0; i < length; ++i ) {
value[i] = xdrDecodeDouble();
}
return value;
}
/**
* Decodes (aka "deserializes") a vector of booleans read from a XDR stream.
*
* @return Decoded boolean vector.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
*/
public final boolean [] xdrDecodeBooleanVector()
throws OncRpcException, IOException {
int length = xdrDecodeInt();
boolean [] value = new boolean[length];
for ( int i = 0; i < length; ++i ) {
value[i] = xdrDecodeBoolean();
}
return value;
}
/**
* Decodes (aka "deserializes") a vector of booleans read from a XDR stream.
*
* @param length of vector to read.
*
* @return Decoded boolean vector.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
*/
public final boolean [] xdrDecodeBooleanFixedVector(int length)
throws OncRpcException, IOException {
boolean [] value = new boolean[length];
for ( int i = 0; i < length; ++i ) {
value[i] = xdrDecodeBoolean();
}
return value;
}
/**
* Decodes (aka "deserializes") a vector of strings read from a XDR stream.
*
* @return Decoded String vector.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
*/
public final String [] xdrDecodeStringVector()
throws OncRpcException, IOException {
int length = xdrDecodeInt();
String [] value = new String[length];
for ( int i = 0; i < length; ++i ) {
value[i] = xdrDecodeString();
}
return value;
}
/**
* Decodes (aka "deserializes") a vector of strings read from a XDR stream.
*
* @param length of vector to read.
*
* @return Decoded String vector.
*
* @throws OncRpcException if an ONC/RPC error occurs.
* @throws IOException if an I/O error occurs.
*/
public final String [] xdrDecodeStringFixedVector(int length)
throws OncRpcException, IOException {
String [] value = new String[length];
for ( int i = 0; i < length; ++i ) {
value[i] = xdrDecodeString();
}
return value;
}
/**
* Set the character encoding for deserializing strings.
*
* @param characterEncoding the encoding to use for deserializing strings.
* If <code>null</code>, the system's default encoding is to be used.
*/
public void setCharacterEncoding(String characterEncoding) {
this.characterEncoding = characterEncoding;
}
/**
* Get the character encoding for deserializing strings.
*
* @return the encoding currently used for deserializing strings.
* If <code>null</code>, then the system's default encoding is used.
*/
public String getCharacterEncoding() {
return characterEncoding;
}
/**
* Encoding to use when deserializing strings or <code>null</code> if
* the system's default encoding should be used.
*/
private String characterEncoding = null;
}
// End of XdrDecodingStream.java