How to use

testAssignment

method

in

org.apache.cassandra.cql3.functions.ScalarFunction

public Term prepare(String keyspace, ColumnSpecification receiver) throws InvalidRequestException
{
  Function fun = FunctionResolver.get(keyspace, name, terms, receiver.ksName, receiver.cfName, receiver.type);
  if (fun == null)
    throw new InvalidRequestException(String.format("Unknown function %s called", name));
  if (fun.isAggregate())
    throw new InvalidRequestException("Aggregation function are not supported in the where clause");
  ScalarFunction scalarFun = (ScalarFunction) fun;
  // Functions.get() will complain if no function "name" type check with the provided arguments.
  // We still have to validate that the return type matches however
  if (!scalarFun.testAssignment(keyspace, receiver).isAssignable())
    throw new InvalidRequestException(String.format("Type error: cannot assign result of function %s (type %s) to %s (type %s)",
                            scalarFun.name(), scalarFun.returnType().asCQL3Type(),
                            receiver.name, receiver.type.asCQL3Type()));
  if (fun.argTypes().size() != terms.size())
    throw new InvalidRequestException(String.format("Incorrect number of arguments specified for function %s (expected %d, found %d)",
                            fun, fun.argTypes().size(), terms.size()));
  List<Term> parameters = new ArrayList<>(terms.size());
  for (int i = 0; i < terms.size(); i++)
  {
    Term t = terms.get(i).prepare(keyspace, FunctionResolver.makeArgSpec(receiver.ksName, receiver.cfName, scalarFun, i));
    parameters.add(t);
  }
  return new FunctionCall(scalarFun, parameters);
}

public Term prepare(String keyspace, ColumnSpecification receiver) throws InvalidRequestException
{
  Function fun = FunctionResolver.get(keyspace, name, terms, receiver.ksName, receiver.cfName, receiver.type);
  if (fun == null)
    throw new InvalidRequestException(String.format("Unknown function %s called", name));
  if (fun.isAggregate())
    throw new InvalidRequestException("Aggregation function are not supported in the where clause");
  ScalarFunction scalarFun = (ScalarFunction) fun;
  // Functions.get() will complain if no function "name" type check with the provided arguments.
  // We still have to validate that the return type matches however
  if (!scalarFun.testAssignment(keyspace, receiver).isAssignable())
    throw new InvalidRequestException(String.format("Type error: cannot assign result of function %s (type %s) to %s (type %s)",
                            scalarFun.name(), scalarFun.returnType().asCQL3Type(),
                            receiver.name, receiver.type.asCQL3Type()));
  if (fun.argTypes().size() != terms.size())
    throw new InvalidRequestException(String.format("Incorrect number of arguments specified for function %s (expected %d, found %d)",
                            fun, fun.argTypes().size(), terms.size()));
  List<Term> parameters = new ArrayList<>(terms.size());
  for (int i = 0; i < terms.size(); i++)
  {
    Term t = terms.get(i).prepare(keyspace, FunctionResolver.makeArgSpec(receiver.ksName, receiver.cfName, scalarFun, i));
    parameters.add(t);
  }
  return new FunctionCall(scalarFun, parameters);
}

public Term prepare(String keyspace, ColumnSpecification receiver) throws InvalidRequestException
{
  Function fun = FunctionResolver.get(keyspace, name, terms, receiver.ksName, receiver.cfName, receiver.type);
  if (fun == null)
    throw new InvalidRequestException(String.format("Unknown function %s called", name));
  if (fun.isAggregate())
    throw new InvalidRequestException("Aggregation function are not supported in the where clause");
  ScalarFunction scalarFun = (ScalarFunction) fun;
  // Functions.get() will complain if no function "name" type check with the provided arguments.
  // We still have to validate that the return type matches however
  if (!scalarFun.testAssignment(keyspace, receiver).isAssignable())
    throw new InvalidRequestException(String.format("Type error: cannot assign result of function %s (type %s) to %s (type %s)",
                            scalarFun.name(), scalarFun.returnType().asCQL3Type(),
                            receiver.name, receiver.type.asCQL3Type()));
  if (fun.argTypes().size() != terms.size())
    throw new InvalidRequestException(String.format("Incorrect number of arguments specified for function %s (expected %d, found %d)",
                            fun, fun.argTypes().size(), terms.size()));
  List<Term> parameters = new ArrayList<>(terms.size());
  for (int i = 0; i < terms.size(); i++)
  {
    Term t = terms.get(i).prepare(keyspace, FunctionResolver.makeArgSpec(receiver.ksName, receiver.cfName, scalarFun, i));
    parameters.add(t);
  }
  return new FunctionCall(scalarFun, parameters);
}