package org.infinispan.marshall.exts;
import java.io.IOException;
import java.io.ObjectInput;
import java.io.ObjectOutput;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;
import java.util.TreeMap;
import java.util.concurrent.ConcurrentHashMap;
import org.infinispan.commons.equivalence.Equivalence;
import org.infinispan.commons.equivalence.EquivalentHashMap;
import org.infinispan.commons.marshall.AbstractExternalizer;
import org.infinispan.commons.marshall.MarshallUtil;
import org.infinispan.commons.util.FastCopyHashMap;
import org.infinispan.commons.util.Util;
import org.infinispan.container.versioning.EntryVersionsMap;
import org.infinispan.distribution.util.ReadOnlySegmentAwareMap;
import org.infinispan.marshall.core.Ids;
import org.jboss.marshalling.util.IdentityIntMap;
/**
* Map externalizer for all map implementations except immutable maps and singleton maps, i.e. FastCopyHashMap, HashMap,
* TreeMap.
*
* @author Galder ZamarreƱo
* @since 4.0
*/
public class MapExternalizer extends AbstractExternalizer<Map> {
private static final int HASHMAP = 0;
private static final int TREEMAP = 1;
private static final int FASTCOPYHASHMAP = 2;
private static final int EQUIVALENTHASHMAP = 3;
private static final int CONCURRENTHASHMAP = 4;
private static final int ENTRYVERSIONMAP = 5;
private static final int SINGLETONMAP = 6;
private static final int EMPTYMAP = 7;
private final IdentityIntMap<Class<?>> numbers = new IdentityIntMap<Class<?>>(9);
public MapExternalizer() {
numbers.put(HashMap.class, HASHMAP);
numbers.put(ReadOnlySegmentAwareMap.class, HASHMAP);
numbers.put(TreeMap.class, TREEMAP);
numbers.put(FastCopyHashMap.class, FASTCOPYHASHMAP);
numbers.put(EquivalentHashMap.class, EQUIVALENTHASHMAP);
numbers.put(ConcurrentHashMap.class, CONCURRENTHASHMAP);
numbers.put(EntryVersionsMap.class, ENTRYVERSIONMAP);
numbers.put(getPrivateSingletonMapClass(), SINGLETONMAP);
numbers.put(getPrivateEmptyMapClass(), EMPTYMAP);
}
@Override
public void writeObject(ObjectOutput output, Map map) throws IOException {
int number = numbers.get(map.getClass(), -1);
output.write(number);
switch (number) {
case HASHMAP:
case TREEMAP:
case CONCURRENTHASHMAP:
case ENTRYVERSIONMAP:
MarshallUtil.marshallMap(map, output);
break;
case EQUIVALENTHASHMAP:
EquivalentHashMap equivalentMap = (EquivalentHashMap) map;
output.writeObject(equivalentMap.getKeyEquivalence());
output.writeObject(equivalentMap.getValueEquivalence());
MarshallUtil.marshallMap(map, output);
break;
case FASTCOPYHASHMAP:
//copy the map to avoid ConcurrentModificationException
MarshallUtil.marshallMap(((FastCopyHashMap<?, ?>) map).clone(), output);
break;
case SINGLETONMAP:
Map.Entry singleton = (Map.Entry) map.entrySet().iterator().next();
output.writeObject(singleton.getKey());
output.writeObject(singleton.getValue());
break;
default:
break;
}
}
@Override
public Map readObject(ObjectInput input) throws IOException, ClassNotFoundException {
int magicNumber = input.readUnsignedByte();
switch (magicNumber) {
case HASHMAP:
return MarshallUtil.unmarshallMap(input, HashMap::new);
case TREEMAP:
return MarshallUtil.unmarshallMap(input, size -> new TreeMap<>());
case FASTCOPYHASHMAP:
return MarshallUtil.unmarshallMap(input, FastCopyHashMap::new);
case EQUIVALENTHASHMAP:
Equivalence<Object> keyEq = (Equivalence<Object>) input.readObject();
Equivalence<Object> valueEq = (Equivalence<Object>) input.readObject();
return MarshallUtil.unmarshallMap(input, size -> new EquivalentHashMap<>(keyEq, valueEq));
case CONCURRENTHASHMAP:
return MarshallUtil.unmarshallMap(input, ConcurrentHashMap::new);
case ENTRYVERSIONMAP:
return MarshallUtil.unmarshallMap(input, EntryVersionsMap::new);
case SINGLETONMAP:
return Collections.singletonMap(input.readObject(), input.readObject());
case EMPTYMAP:
return Collections.emptyMap();
default:
throw new IllegalStateException("Unknown Map type: " + magicNumber);
}
}
@Override
public Integer getId() {
return Ids.MAPS;
}
@Override
public Set<Class<? extends Map>> getTypeClasses() {
return Util.<Class<? extends Map>>asSet(
HashMap.class, TreeMap.class, FastCopyHashMap.class, EquivalentHashMap.class,
ReadOnlySegmentAwareMap.class, ConcurrentHashMap.class,
EntryVersionsMap.class, getPrivateSingletonMapClass(), getPrivateEmptyMapClass());
}
private static Class<? extends Map> getPrivateSingletonMapClass() {
return getMapClass("java.util.Collections$SingletonMap");
}
private static Class<? extends Map> getPrivateEmptyMapClass() {
return getMapClass("java.util.Collections$EmptyMap");
}
private static Class<? extends Map> getMapClass(String className) {
return Util.<Map>loadClass(className, Map.class.getClassLoader());
}
}