@Override
public ScalarFunctionImplementation specialize(
BoundVariables boundVariables,
int arity,
TypeManager typeManager,
FunctionRegistry functionRegistry) {
Type fromType = boundVariables.getTypeVariable("F");
Type toType = boundVariables.getTypeVariable("T");
Class<?> returnType = Primitives.wrap(toType.getJavaType());
MethodHandle tryCastHandle;
if (fromType.equals(UNKNOWN)) {
tryCastHandle = dropArguments(constant(returnType, null), 0, Void.class);
} else {
// the resulting method needs to return a boxed type
Signature signature = functionRegistry.getCoercion(fromType, toType);
MethodHandle coercion =
functionRegistry.getScalarFunctionImplementation(signature).getMethodHandle();
coercion = coercion.asType(methodType(returnType, coercion.type()));
MethodHandle exceptionHandler =
dropArguments(constant(returnType, null), 0, RuntimeException.class);
tryCastHandle = catchException(coercion, RuntimeException.class, exceptionHandler);
}
return new ScalarFunctionImplementation(
true, ImmutableList.of(true), tryCastHandle, isDeterministic());
}
@Override
public ScalarFunctionImplementation specialize(
BoundVariables boundVariables,
int arity,
TypeManager typeManager,
FunctionRegistry functionRegistry) {
checkArgument(boundVariables.getTypeVariables().size() == 1, "Expected only one type");
Type type = boundVariables.getTypeVariable("T");
MethodHandle identity = MethodHandles.identity(type.getJavaType());
return new ScalarFunctionImplementation(
false, ImmutableList.of(false), identity, isDeterministic());
}
@Override
public ScalarFunctionImplementation specialize(
BoundVariables boundVariables,
int arity,
TypeManager typeManager,
FunctionRegistry functionRegistry) {
Type argumentType = boundVariables.getTypeVariable("T");
Type returnType = boundVariables.getTypeVariable("U");
return new ScalarFunctionImplementation(
true,
ImmutableList.of(true, false),
METHOD_HANDLE.asType(
METHOD_HANDLE
.type()
.changeReturnType(wrap(returnType.getJavaType()))
.changeParameterType(0, wrap(argumentType.getJavaType()))),
isDeterministic());
}
@Override
public ScalarFunctionImplementation specialize(
BoundVariables boundVariables,
int arity,
TypeManager typeManager,
FunctionRegistry functionRegistry) {
Type type = boundVariables.getTypeVariable("T");
return new ScalarFunctionImplementation(
false, ImmutableList.of(false, false), METHOD_HANDLE.bindTo(type), isDeterministic());
}
@Override
public ScalarFunctionImplementation specialize(
BoundVariables boundVariables,
int arity,
TypeManager typeManager,
FunctionRegistry functionRegistry) {
Type elementType = boundVariables.getTypeVariable("T");
MethodHandle greaterThanFunction =
functionRegistry
.getScalarFunctionImplementation(
internalOperator(GREATER_THAN, BOOLEAN, ImmutableList.of(elementType, elementType)))
.getMethodHandle();
MethodHandle method = METHOD_HANDLE.bindTo(greaterThanFunction).bindTo(elementType);
return new ScalarFunctionImplementation(
false, ImmutableList.of(false, false), method, isDeterministic());
}
