com.netflix.astyanax.serializers.PrefixedSerializer Maven / Gradle / Ivy
package com.netflix.astyanax.serializers;
import java.nio.ByteBuffer;
import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.netflix.astyanax.Serializer;
import com.netflix.astyanax.connectionpool.exceptions.SerializationException;
public class PrefixedSerializer extends AbstractSerializer {
private static Logger log = LoggerFactory.getLogger(PrefixedSerializer.class);
P prefix;
Serializer prefixSerializer;
ByteBuffer prefixBytes;
Serializer suffixSerializer;
public PrefixedSerializer(P prefix, Serializer
prefixSerializer, Serializer suffixSerializer) {
this.prefix = prefix;
this.prefixSerializer = prefixSerializer;
this.suffixSerializer = suffixSerializer;
prefixBytes = prefixSerializer.toByteBuffer(prefix);
prefixBytes.rewind();
}
@Override
public ByteBuffer toByteBuffer(S s) {
if (s == null) {
return null;
}
ByteBuffer sb = suffixSerializer.toByteBuffer(s);
sb.rewind();
ByteBuffer bb = ByteBuffer.allocate(prefixBytes.remaining() + sb.remaining());
bb.put(prefixBytes.slice());
bb.put(sb);
bb.rewind();
return bb;
}
@Override
public S fromByteBuffer(ByteBuffer bytes) throws SerializationException {
if ((bytes == null) || !bytes.hasArray()) {
return null;
}
ByteBuffer dup = bytes.duplicate();
if (compareByteArrays(prefixBytes.array(),
prefixBytes.arrayOffset() + prefixBytes.position(),
prefixBytes.remaining(), dup.array(), dup.arrayOffset()
+ dup.position(), prefixBytes.remaining()) != 0) {
log.error("Unprefixed value received, throwing exception...");
throw new SerializationException("Unexpected prefix value");
}
dup.position(prefixBytes.remaining());
S s = suffixSerializer.fromByteBuffer(dup);
return s;
}
@Override
public List fromBytesList(List list) {
List objList = new ArrayList(list.size());
for (ByteBuffer s : list) {
try {
ByteBuffer bb = s.slice();
objList.add(fromByteBuffer(bb));
}
catch (SerializationException e) {
// not a prefixed key, discard
log.warn("Unprefixed value received, discarding...");
}
}
return objList;
}
@Override
public Map fromBytesMap(Map map) {
Map objMap = new LinkedHashMap(computeInitialHashSize(map.size()));
for (Entry entry : map.entrySet()) {
try {
ByteBuffer bb = entry.getKey().slice();
objMap.put(fromByteBuffer(bb), entry.getValue());
}
catch (SerializationException e) {
// not a prefixed key, discard
log.warn("Unprefixed value received, discarding...");
}
}
return objMap;
}
private static int compareByteArrays(byte[] bytes1, int offset1, int len1, byte[] bytes2, int offset2, int len2) {
if (null == bytes1) {
if (null == bytes2) {
return 0;
}
else {
return -1;
}
}
if (null == bytes2) {
return 1;
}
if (len1 < 0) {
len1 = bytes1.length - offset1;
}
if (len2 < 0) {
len2 = bytes2.length - offset2;
}
int minLength = Math.min(len1, len2);
for (int i = 0; i < minLength; i++) {
int i1 = offset1 + i;
int i2 = offset2 + i;
if (bytes1[i1] == bytes2[i2]) {
continue;
}
// compare non-equal bytes as unsigned
return (bytes1[i1] & 0xFF) < (bytes2[i2] & 0xFF) ? -1 : 1;
}
if (len1 == len2) {
return 0;
}
else {
return (len1 < len2) ? -1 : 1;
}
}
}