private FunctionDescProto findFunction(
String signature,
FunctionType type,
List<TajoDataTypes.DataType> params,
boolean strictTypeCheck) {
List<FunctionDescProto> candidates = Lists.newArrayList();
if (functions.containsKey(signature)) {
if (strictTypeCheck) {
for (FunctionDescProto func : functions.get(signature)) {
if (func.getSignature().getType() == type
&& func.getSignature().getParameterTypesList().equals(params)) {
candidates.add(func);
}
}
} else {
for (FunctionDescProto func : functions.get(signature)) {
if (func.getSignature().getParameterTypesList() != null
&& CatalogUtil.isMatchedFunction(
func.getSignature().getParameterTypesList(), params)) {
candidates.add(func);
}
}
}
}
// if there are more than one function candidates, we choose the nearest matched function.
if (candidates.size() > 0) {
return findNearestMatchedFunction(candidates);
} else {
return null;
}
}
private FunctionDescProto findFunctionStrictType(
FunctionDescProto target, boolean strictTypeCheck) {
return findFunction(
target.getSignature().getName(),
target.getSignature().getType(),
target.getSignature().getParameterTypesList(),
strictTypeCheck);
}
@Override
public int compare(FunctionDescProto o1, FunctionDescProto o2) {
List<DataType> types1 = o1.getSignature().getParameterTypesList();
List<DataType> types2 = o2.getSignature().getParameterTypesList();
int minLen = Math.min(types1.size(), types2.size());
for (int i = 0; i < minLen; i++) {
int cmpVal = types1.get(i).getType().getNumber() - types2.get(i).getType().getNumber();
if (cmpVal != 0) {
return cmpVal;
}
}
return types1.size() - types2.size();
}
private FunctionDescProto findFunction(String signature, List<TajoDataTypes.DataType> params) {
List<FunctionDescProto> candidates = Lists.newArrayList();
if (functions.containsKey(signature)) {
for (FunctionDescProto func : functions.get(signature)) {
if (func.getSignature().getParameterTypesList() != null
&& func.getSignature().getParameterTypesList().equals(params)) {
candidates.add(func);
}
}
}
/*
*
* FALL BACK to look for nearest match
* WORKING BUT BAD WAY TO IMPLEMENT.I WOULD RATHER implement compareTo in FunctionDesc to keep them
* in sorted order of param types LIKE INT1 SHOULD BE BEFORE INT2 should be before INT3 so on.
* Due to possibility of multiple parameters and types the permutation and combinations are endless
* to implement compareTo so decided to take the shortcut.
*
* */
if (functions.containsKey(signature)) {
for (FunctionDescProto func : functions.get(signature)) {
if (func.getSignature().getParameterTypesList() != null
&& CatalogUtil.isMatchedFunction(
func.getSignature().getParameterTypesList(), params)) {
candidates.add(func);
}
}
// if there are more than one function candidates, we choose the nearest matched function.
if (candidates.size() > 0) {
return findNearestMatchedFunction(candidates);
} else {
return null;
}
}
return null;
}
@Override
public ReturnState createFunction(RpcController controller, FunctionDescProto funcDesc) {
try {
FunctionSignature signature = FunctionSignature.create(funcDesc);
if (functions.containsKey(funcDesc.getSignature())) {
FunctionDescProto found = findFunctionStrictType(funcDesc, true);
if (found != null) {
return errDuplicateFunction(signature.toString());
}
}
TUtil.putToNestedList(functions, funcDesc.getSignature().getName(), funcDesc);
return OK;
} catch (Throwable t) {
printStackTraceIfError(LOG, t);
return returnError(t);
}
}
public static FunctionSignature create(FunctionDescProto proto) {
return new FunctionSignature(
proto.getSignature().getName(),
proto.getSignature().getType(),
proto.getSignature().getParameterTypesList());
}