package org.apache.ibatis.cache.decorators;
import org.apache.ibatis.cache.Cache;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.locks.ReadWriteLock;
public class TransactionalCache implements Cache {
private Cache delegate;
private boolean clearOnCommit;
private Map<Object, AddEntry> entriesToAddOnCommit;
private Map<Object, RemoveEntry> entriesToRemoveOnCommit;
public TransactionalCache(Cache delegate) {
this.delegate = delegate;
this.clearOnCommit = false;
this.entriesToAddOnCommit = new HashMap<Object, AddEntry>();
this.entriesToRemoveOnCommit = new HashMap<Object, RemoveEntry>();
}
public String getId() {
return delegate.getId();
}
public int getSize() {
return delegate.getSize();
}
public Object getObject(Object key) {
return delegate.getObject(key);
}
public ReadWriteLock getReadWriteLock() {
return delegate.getReadWriteLock();
}
public void putObject(Object key, Object object) {
entriesToRemoveOnCommit.remove(key);
entriesToAddOnCommit.put(key, new AddEntry(delegate, key, object));
}
public Object removeObject(Object key) {
entriesToAddOnCommit.remove(key);
entriesToRemoveOnCommit.put(key, new RemoveEntry(delegate, key));
return delegate.getObject(key);
}
public void clear() {
reset();
clearOnCommit = true;
}
public void commit() {
delegate.getReadWriteLock().writeLock().lock();
try {
if (clearOnCommit) {
delegate.clear();
} else {
for (RemoveEntry entry : entriesToRemoveOnCommit.values()) {
entry.commit();
}
}
for (AddEntry entry : entriesToAddOnCommit.values()) {
entry.commit();
}
reset();
} finally {
delegate.getReadWriteLock().writeLock().unlock();
}
}
public void rollback() {
reset();
}
private void reset() {
clearOnCommit = false;
entriesToRemoveOnCommit.clear();
entriesToAddOnCommit.clear();
}
private static class AddEntry {
private Cache cache;
private Object key;
private Object value;
public AddEntry(Cache cache, Object key, Object value) {
this.cache = cache;
this.key = key;
this.value = value;
}
public void commit() {
cache.putObject(key, value);
}
}
private static class RemoveEntry {
private Cache cache;
private Object key;
public RemoveEntry(Cache cache, Object key) {
this.cache = cache;
this.key = key;
}
public void commit() {
cache.removeObject(key);
}
}
}
|