<Sound Dev> [9] Review Request: 8146144 Incorrect behaviour of AudioSystem.getTargetFormats/getTargetEncodings/isConversionSupported

[Sergey Bylokhov]

Hello, Audio Guru.

Please review the fix for jdk9.

The change contains the fixes for two quite similar issues:

- A few methods in AudioSystem class should work uniformly. For example 
AudioSystem.getAudioInputStream() does not throw an exception if the 
source/target formats are unsupported by our converters. The reason is 
simple, this method has such code:
   if (sourceStream.getFormat().matches(targetFormat)) {
     return sourceStream;
   }
So it returns the source stream without check of our converters. But if 
an exception was not thrown, means that 
AudioSystem.isConversionSupported() should return true for such formats, 
AudioSystem.getTargetFormats() should contain format which the matchs to 
the source format, and AudioSystem.getTargetEncodings() should contain 
the source encoding.
All this were fixed in AudioSystem.java


- Some of the methods in our converters also should work uniformly. Like 
getTargetFormats(encoding, sourceFormat) and getTargetEncodings(format) 
should have the same source checks, otherwise some of these methods can 
return encoding/format which are not present in the second method.
For example PCMtoPCMCodec.java: getTargetEncodings() returns the list of 
PCM_SIGNED and PCM_UNSIGNED for any source formats of type 
PCM_SIG/UNSIG, but the getTargetFormats() returns some formats only for 
a specific sampleSize(8/16). As a fix an the checks are unified everywhere.
- Another problem in the converters is that getAudioInputStream() do not 
throw an exception if the source and target encoding are the same. As a 
fix the isConversionSupported is added at the beginning of each method. 
So each converter will be responsible only for formats it know.


Bug: https://bugs.openjdk.java.net/browse/JDK-8146144
Webrev can be found at: http://cr.openjdk.java.net/~serb/8146144/webrev.01

-- 
Best regards, Sergey.