package storm.trident.state.map;
import storm.trident.state.TransactionalValue;
import storm.trident.state.ValueUpdater;
import java.util.ArrayList;
import java.util.List;
public class TransactionalMap<T> implements MapState<T> {
public static <T> MapState<T> build(IBackingMap<TransactionalValue> backing) {
return new TransactionalMap<T>(backing);
}
CachedBatchReadsMap<TransactionalValue> _backing;
Long _currTx;
protected TransactionalMap(IBackingMap<TransactionalValue> backing) {
_backing = new CachedBatchReadsMap(backing);
}
@Override
public List<T> multiGet(List<List<Object>> keys) {
List<CachedBatchReadsMap.RetVal<TransactionalValue>> vals = _backing.multiGet(keys);
List<T> ret = new ArrayList<T>(vals.size());
for(CachedBatchReadsMap.RetVal<TransactionalValue> retval: vals) {
TransactionalValue v = retval.val;
if(v!=null) {
ret.add((T) v.getVal());
} else {
ret.add(null);
}
}
return ret;
}
@Override
public List<T> multiUpdate(List<List<Object>> keys, List<ValueUpdater> updaters) {
List<CachedBatchReadsMap.RetVal<TransactionalValue>> curr = _backing.multiGet(keys);
List<TransactionalValue> newVals = new ArrayList<TransactionalValue>(curr.size());
List<List<Object>> newKeys = new ArrayList();
List<T> ret = new ArrayList<T>();
for(int i=0; i<curr.size(); i++) {
CachedBatchReadsMap.RetVal<TransactionalValue> retval = curr.get(i);
TransactionalValue<T> val = retval.val;
ValueUpdater<T> updater = updaters.get(i);
TransactionalValue<T> newVal;
boolean changed = false;
if(val==null) {
newVal = new TransactionalValue<T>(_currTx, updater.update(null));
changed = true;
} else {
if(_currTx!=null && _currTx.equals(val.getTxid()) && !retval.cached) {
newVal = val;
} else {
newVal = new TransactionalValue<T>(_currTx, updater.update(val.getVal()));
changed = true;
}
}
ret.add(newVal.getVal());
if(changed) {
newVals.add(newVal);
newKeys.add(keys.get(i));
}
}
if(!newKeys.isEmpty()) {
_backing.multiPut(newKeys, newVals);
}
return ret;
}
@Override
public void multiPut(List<List<Object>> keys, List<T> vals) {
List<TransactionalValue> newVals = new ArrayList<TransactionalValue>(vals.size());
for(T val: vals) {
newVals.add(new TransactionalValue<T>(_currTx, val));
}
_backing.multiPut(keys, newVals);
}
@Override
public void beginCommit(Long txid) {
_currTx = txid;
_backing.reset();
}
@Override
public void commit(Long txid) {
_currTx = null;
_backing.reset();
}
}