org.xbib.io.compress.lzf.ChunkDecoderFactory Maven / Gradle / Ivy
package org.xbib.io.compress.lzf;
/**
* Simple helper class used for loading {@link ChunkDecoder} implementations,
* based on criteria such as "fastest available". Yes, it looks butt-ugly,
* but does the job. Nonetheless, if anyone has lipstick for this pig, let me
* know.
*/
public class ChunkDecoderFactory {
private static final ChunkDecoderFactory INSTANCE;
static {
INSTANCE = new ChunkDecoderFactory( VanillaChunkDecoder.class);
}
private final Class implClass;
@SuppressWarnings("unchecked")
private ChunkDecoderFactory(Class imp) {
implClass = (Class) imp;
}
/**
* Method to use for getting decompressor instance that uses the most
* optimal available methods for underlying data access. It should be safe
* to call this method as implementations are dynamically loaded; however,
* on some non-standard platforms it may be necessary to either directly
* load instances, or use {@link #safeInstance()}.
*/
public static ChunkDecoder optimalInstance() {
try {
return INSTANCE.implClass.newInstance();
} catch (Exception e) {
throw new IllegalStateException("Failed to load a ChunkDecoder instance (" + e.getClass().getName() + "): "
+ e.getMessage(), e);
}
}
/**
* Method that can be used to ensure that a "safe" decompressor instance is
* loaded. Safe here means that it should work on any and all Java
* platforms.
*/
public static ChunkDecoder safeInstance() {
// this will always succeed loading; no need to use dynamic class loading or instantiation
return new VanillaChunkDecoder();
}
}