[HARMONY-150] java.nio.charset.Charset.decode(in) doesn't use the same cached decoder.

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Component/s: Classlib
• Assignee: Tim Ellison
• Reporter: Richard Liang
• Created: 02/Mar/06 11:51
• Updated: 30/Mar/06 17:56
• Resolved: 29/Mar/06 21:29

Description

java.nio.charset.Charset.decode(in) doesn't use the same cached decoder.
As spec says, "An invocation of this method upon a charset cs returns the same result as the expression cs.newDecoder() .onMalformedInput(CodingErrorAction.REPLACE) .onUnmappableCharacter(CodingErrorAction.REPLACE) .decode(bb); except that it is potentially more efficient because it can cache decoders between successive invocations. "
RI always uses the same cached decoder (the same reference) for the same name charset. For details, please refer to the test case below:
======== test case output =====
RI 5.0 passes the test case while Harmony fails.

======== test case===========
/*

• test cached decoder
  */
  public void testCachedDecoder() throws Exception
  Unknown macro: { MockCachedCharset cs1 = new MockCachedCharset("CachedCharset",null); MockCachedCharset cs2 = new MockCachedCharset("CachedCharset",null); ByteBuffer in = ByteBuffer.wrap(new byte[]{0x00}); cs1.decode(in); in.flip(); cs2.decode(in); in.flip(); }

  /*

• Mock Charset for cached decoder test
  */
  static class MockCachedCharset extends Charset{

public MockCachedCharset(String canonicalName, String[] aliases)

{ super(canonicalName, aliases); }

public boolean contains(Charset charset)

{ return false; }

public CharsetEncoder newEncoder()

{ return null; }

public CharsetDecoder newDecoder()

{ return new MockCachedDecoder(this); }

}
/*

• Mock decoder. Only one caller is permitted.
  */
  static class MockCachedDecoder extends CharsetDecoder {
  static MockCachedDecoder caller = null;

public MockCachedDecoder(Charset cs)

{ super(cs, 1, 10); }

/*

• Only one caller is permitted.
• If there's another caller, throw RuntimeException.
  */
  protected CoderResult decodeLoop(ByteBuffer in, CharBuffer out) {
  if(null == caller) { caller = this; }

  else

  Unknown macro: { if(caller != this){ // Another instance throw new RuntimeException(); } }

  return CoderResult.UNDERFLOW;
  }
  }