How to use

getInputParameterSignatures

method

in

com.linkedin.transport.api.udf.StdUDF

@VisibleForTesting
static List<TypeVariableConstraint> getTypeVariableConstraintsForStdUdf(StdUDF stdUdf) {
 Set<GenericTypeSignatureElement> genericTypes = new HashSet<>();
 for (String s : stdUdf.getInputParameterSignatures()) {
  genericTypes.addAll(com.linkedin.transport.typesystem.TypeSignature.parse(s).getGenericTypeSignatureElements());
 }
 genericTypes.addAll(com.linkedin.transport.typesystem.TypeSignature.parse(stdUdf.getOutputParameterSignature())
   .getGenericTypeSignatureElements());
 return genericTypes.stream().map(t -> typeVariable(t.toString())).collect(Collectors.toList());
}

@VisibleForTesting
static List<TypeVariableConstraint> getTypeVariableConstraintsForStdUdf(StdUDF stdUdf) {
 Set<GenericTypeSignatureElement> genericTypes = new HashSet<>();
 for (String s : stdUdf.getInputParameterSignatures()) {
  genericTypes.addAll(com.linkedin.transport.typesystem.TypeSignature.parse(s).getGenericTypeSignatureElements());
 }
 genericTypes.addAll(com.linkedin.transport.typesystem.TypeSignature.parse(stdUdf.getOutputParameterSignature())
   .getGenericTypeSignatureElements());
 return genericTypes.stream().map(t -> typeVariable(t.toString())).collect(Collectors.toList());
}

protected StdUdfWrapper(StdUDF stdUDF) {
 super(new Signature(((TopLevelStdUDF) stdUDF).getFunctionName(), FunctionKind.SCALAR,
   getTypeVariableConstraintsForStdUdf(stdUDF), ImmutableList.of(),
   parseTypeSignature(stdUDF.getOutputParameterSignature()), stdUDF.getInputParameterSignatures()
   .stream()
   .map(TypeSignature::parseTypeSignature)
   .collect(Collectors.toList()), false));
 _functionDescription = ((TopLevelStdUDF) stdUDF).getFunctionDescription();
}

protected StdUdfWrapper(StdUDF stdUDF) {
 super(new Signature(((TopLevelStdUDF) stdUDF).getFunctionName(), FunctionKind.SCALAR,
   getTypeVariableConstraintsForStdUdf(stdUDF), ImmutableList.of(),
   parseTypeSignature(stdUDF.getOutputParameterSignature()), stdUDF.getInputParameterSignatures()
   .stream()
   .map(TypeSignature::parseTypeSignature)
   .collect(Collectors.toList()), false));
 _functionDescription = ((TopLevelStdUDF) stdUDF).getFunctionDescription();
}

boolean atLeastOneInputParametersSignaturesBindingSuccess = false;
for (StdUDF stdUdf: stdUdfImplementations) {
 List<String> inputParameterSignatures = stdUdf.getInputParameterSignatures();
 if (inputParameterSignatures.size() != dataTypes.length) {
  continue;

boolean atLeastOneInputParametersSignaturesBindingSuccess = false;
for (StdUDF stdUdf: stdUdfImplementations) {
 List<String> inputParameterSignatures = stdUdf.getInputParameterSignatures();
 if (inputParameterSignatures.size() != dataTypes.length) {
  continue;

private MethodHandle getMethodHandle(StdUDF stdUDF, TypeManager typeManager, BoundVariables boundVariables,
  boolean[] nullableArguments) {
 Type[] inputTypes = getPrestoTypes(stdUDF.getInputParameterSignatures(), typeManager, boundVariables);
 Type outputType = getPrestoType(stdUDF.getOutputParameterSignature(), typeManager, boundVariables);
 // Generic MethodHandle for eval where all arguments are of type Object
 Class<?>[] genericMethodHandleArgumentTypes = getMethodHandleArgumentTypes(inputTypes, nullableArguments, true);
 MethodHandle genericMethodHandle =
   methodHandle(StdUdfWrapper.class, "evalInternal", genericMethodHandleArgumentTypes).bindTo(this);
 Class<?>[] specificMethodHandleArgumentTypes = getMethodHandleArgumentTypes(inputTypes, nullableArguments, false);
 Class<?> specificMethodHandleReturnType = getMethodHandleJavaType(outputType, true, 0);
 MethodType specificMethodType =
   MethodType.methodType(specificMethodHandleReturnType, specificMethodHandleArgumentTypes);
 // Specific MethodHandle required by presto where argument types map to the type signature
 MethodHandle specificMethodHandle = MethodHandles.explicitCastArguments(genericMethodHandle, specificMethodType);
 return MethodHandles.insertArguments(specificMethodHandle, 0, stdUDF, inputTypes,
   outputType instanceof IntegerType);
}

private MethodHandle getMethodHandle(StdUDF stdUDF, TypeManager typeManager, BoundVariables boundVariables,
  boolean[] nullableArguments) {
 Type[] inputTypes = getPrestoTypes(stdUDF.getInputParameterSignatures(), typeManager, boundVariables);
 Type outputType = getPrestoType(stdUDF.getOutputParameterSignature(), typeManager, boundVariables);
 // Generic MethodHandle for eval where all arguments are of type Object
 Class<?>[] genericMethodHandleArgumentTypes = getMethodHandleArgumentTypes(inputTypes, nullableArguments, true);
 MethodHandle genericMethodHandle =
   methodHandle(StdUdfWrapper.class, "evalInternal", genericMethodHandleArgumentTypes).bindTo(this);
 Class<?>[] specificMethodHandleArgumentTypes = getMethodHandleArgumentTypes(inputTypes, nullableArguments, false);
 Class<?> specificMethodHandleReturnType = getMethodHandleJavaType(outputType, true, 0);
 MethodType specificMethodType =
   MethodType.methodType(specificMethodHandleReturnType, specificMethodHandleArgumentTypes);
 // Specific MethodHandle required by presto where argument types map to the type signature
 MethodHandle specificMethodHandle = MethodHandles.explicitCastArguments(genericMethodHandle, specificMethodType);
 return MethodHandles.insertArguments(specificMethodHandle, 0, stdUDF, inputTypes,
   outputType instanceof IntegerType);
}