+++ /dev/null
-/* Copyright (C) 1999, 2000, 2001 Free Software Foundation
-
- This file is part of libgcj.
-
-This software is copyrighted work licensed under the terms of the
-Libgcj License. Please consult the file "LIBGCJ_LICENSE" for
-details. */
-
-package gnu.gcj.convert;
-
-public abstract class BytesToUnicode extends IOConverter
-{
- /** Buffer to read bytes from.
- * The characters inbuffer[inpos] ... inbuffer[inlength-1] are available. */
- public byte[] inbuffer;
- /** Starting index in buffer to read bytes from. */
- public int inpos;
- /** End of valid bytes in buffer. */
- public int inlength;
-
- // The name of the default encoding.
- static String defaultEncoding;
-
- /* These keep a small cache of decoders for reuse. The array holds
- the actual decoders. The currCachePos is the next value we are
- going to replace in the cache. We don't just throw the data away
- if the cache is full, because if the cache filled up with stuff
- we don't need then the cache would be worthless. We instead
- circulate through the cache the implement kind of an LRU
- algorithm. */
- private static final int CACHE_SIZE = 4; // A power of 2 for speed
- private static BytesToUnicode[] decoderCache
- = new BytesToUnicode[CACHE_SIZE];
- private static int currCachePos = 0;
-
- public abstract String getName();
-
- public static BytesToUnicode getDefaultDecoder()
- {
- try
- {
- synchronized (BytesToUnicode.class)
- {
- if (defaultEncoding == null)
- {
- String encoding
- = canonicalize (System.getProperty("file.encoding",
- "8859_1"));
- String className = "gnu.gcj.convert.Input_" + encoding;
- try
- {
- Class defaultDecodingClass = Class.forName(className);
- defaultEncoding = encoding;
- }
- catch (ClassNotFoundException ex)
- {
- throw new NoClassDefFoundError("missing default encoding "
- + encoding + " (class "
- + className
- + " not found)");
- }
- }
- }
- return getDecoder (defaultEncoding);
- }
- catch (Throwable ex)
- {
- return new Input_8859_1();
- }
- }
-
- /** Get a byte-stream->char-stream converter given an encoding name. */
- public static BytesToUnicode getDecoder (String encoding)
- throws java.io.UnsupportedEncodingException
- {
- /* First hunt in our cache to see if we have a decoder that is
- already allocated. */
- synchronized (BytesToUnicode.class)
- {
- int i;
- for (i = 0; i < decoderCache.length; ++i)
- {
- if (decoderCache[i] != null
- && encoding.equals(decoderCache[i].getName ()))
- {
- BytesToUnicode rv = decoderCache[i];
- decoderCache[i] = null;
- return rv;
- }
- }
- }
-
- // It's not in the cache, so now we have to do real work.
- String className = "gnu.gcj.convert.Input_" + canonicalize (encoding);
- Class decodingClass;
- try
- {
- decodingClass = Class.forName(className);
- return (BytesToUnicode) decodingClass.newInstance();
- }
- catch (Throwable ex)
- {
- try
- {
- // We pass the original name to iconv and let it handle
- // its own aliasing.
- return new Input_iconv (encoding);
- }
- catch (Throwable _)
- {
- throw new java.io.UnsupportedEncodingException(encoding
- + " (" + ex + ')');
- }
- }
- }
-
- /** Make input bytes available to the conversion.
- * @param buffer source of input bytes
- * @param pos index of first available byte
- * @param length one more than index of last available byte
- */
- public final void setInput(byte[] buffer, int pos, int length)
- {
- inbuffer = buffer;
- inpos = pos;
- inlength = length;
- }
-
- /** Convert bytes to chars.
- * Input bytes are taken from this.inbuffer. The available input
- * bytes start at inbuffer[inpos], and end at inbuffer[inlength-1].
- * @param outbuffer buffer for the converted character
- * @param outpos position in buffer to start putting converted characters
- * @param count the maximum number of characters to convert
- * @return number of chars placed in outbuffer.
- * Also, this.inpos is incremented by the number of bytes consumed.
- *
- * (Note the asymmetry in that the input upper bound is inbuffer[inlength-1],
- * while the output upper bound is outbuffer[outpos+count-1]. The
- * justification is that inlength is like the count field of a
- * BufferedInputStream, while the count parameter is like the
- * length parameter of a read request.) The count parameter is
- * also defined to be <= outbuffer.length - outpos (per the specification
- * of the length parameter for a read request).
- */
- public abstract int read (char[] outbuffer, int outpos, int count);
-
- /** Indicate that the converter is resuable.
- * This class keeps track of converters on a per-encoding basis.
- * When done with an encoder you may call this method to indicate
- * that it can be reused later.
- */
- public void done ()
- {
- synchronized (BytesToUnicode.class)
- {
- this.inbuffer = null;
- this.inpos = 0;
- this.inlength = 0;
-
- decoderCache[currCachePos] = this;
- currCachePos = (currCachePos + 1) % CACHE_SIZE;
- }
- }
-}
projects / msp430-gcc.git / blobdiff