Examples with ArrayMapBytecodeExpression com.facebook.presto.sql.gen.ArrayMapBytecodeExpression used on opensource projects

Example 1 with ArrayMapBytecodeExpression

use of com.facebook.presto.sql.gen.ArrayMapBytecodeExpression in project presto by prestodb.

the class ArrayToArrayCast method generateArrayCast.

private static Class<?> generateArrayCast(TypeManager typeManager, Signature elementCastSignature, ScalarFunctionImplementation elementCast) {
    CallSiteBinder binder = new CallSiteBinder();
    ClassDefinition definition = new ClassDefinition(a(PUBLIC, FINAL), CompilerUtils.makeClassName(Joiner.on("$").join("ArrayCast", elementCastSignature.getArgumentTypes().get(0), elementCastSignature.getReturnType())), type(Object.class));
    Parameter session = arg("session", ConnectorSession.class);
    Parameter value = arg("value", Block.class);
    MethodDefinition method = definition.declareMethod(a(PUBLIC, STATIC), "castArray", type(Block.class), session, value);
    Scope scope = method.getScope();
    BytecodeBlock body = method.getBody();
    Variable wasNull = scope.declareVariable(boolean.class, "wasNull");
    body.append(wasNull.set(constantBoolean(false)));
    // cast map elements
    Type fromElementType = typeManager.getType(elementCastSignature.getArgumentTypes().get(0));
    Type toElementType = typeManager.getType(elementCastSignature.getReturnType());
    CachedInstanceBinder cachedInstanceBinder = new CachedInstanceBinder(definition, binder);
    ArrayMapBytecodeExpression newArray = ArrayGeneratorUtils.map(scope, cachedInstanceBinder, fromElementType, toElementType, value, elementCastSignature.getName(), elementCast);
    // return the block
    body.append(newArray.ret());
    MethodDefinition constructorDefinition = definition.declareConstructor(a(PUBLIC));
    BytecodeBlock constructorBody = constructorDefinition.getBody();
    Variable thisVariable = constructorDefinition.getThis();
    constructorBody.comment("super();").append(thisVariable).invokeConstructor(Object.class);
    cachedInstanceBinder.generateInitializations(thisVariable, constructorBody);
    constructorBody.ret();
    return defineClass(definition, Object.class, binder.getBindings(), ArrayToArrayCast.class.getClassLoader());
}