private BlockRead cacheBlock(
String _lookup, BlockCache cache, BlockReader _currBlock, String block) throws IOException {
if ((cache == null) || (_currBlock.getRawSize() > cache.getMaxSize())) {
return new BlockRead(_currBlock, _currBlock.getRawSize());
} else {
/** Try to fully read block for meta data if error try to close file */
byte b[] = null;
try {
b = new byte[(int) _currBlock.getRawSize()];
_currBlock.readFully(b);
} catch (IOException e) {
log.debug("Error full blockRead for file " + fileName + " for block " + block, e);
throw e;
} finally {
_currBlock.close();
}
CacheEntry ce = null;
try {
ce = cache.cacheBlock(_lookup, b);
} catch (Exception e) {
log.warn("Already cached block: " + _lookup, e);
}
if (ce == null)
return new BlockRead(new DataInputStream(new ByteArrayInputStream(b)), b.length);
else return new CachedBlockRead(ce, ce.getBuffer());
}
}
public BlockRead getCachedMetaBlock(String blockName) throws IOException {
String _lookup = fileName + "M" + blockName;
if (_iCache != null) {
CacheEntry cacheEntry = _iCache.getBlock(_lookup);
if (cacheEntry != null) {
return new CachedBlockRead(cacheEntry, cacheEntry.getBuffer());
}
}
return null;
}
private BlockRead getBlock(String _lookup, BlockCache cache, BlockLoader loader)
throws IOException {
BlockReader _currBlock;
if (cache != null) {
CacheEntry cb = null;
cb = cache.getBlock(_lookup);
if (cb != null) {
return new CachedBlockRead(cb, cb.getBuffer());
}
}
/** grab the currBlock at this point the block is still in the data stream */
_currBlock = loader.get();
/** If the block is bigger than the cache just return the stream */
return cacheBlock(_lookup, cache, _currBlock, loader.getInfo());
}