Examples with GenericUDFStruct org.apache.hadoop.hive.ql.udf.generic.GenericUDFStruct used on opensource projects

Example 1 with GenericUDFStruct

use of org.apache.hadoop.hive.ql.udf.generic.GenericUDFStruct in project hive by apache.

the class ConstantPropagateProcFactory method evaluateFunction.

/**
   * Evaluate UDF
   *
   * @param udf UDF object
   * @param exprs
   * @param oldExprs
   * @return null if expression cannot be evaluated (not all parameters are constants). Or evaluated
   *         ExprNodeConstantDesc if possible.
   * @throws HiveException
   */
private static ExprNodeDesc evaluateFunction(GenericUDF udf, List<ExprNodeDesc> exprs, List<ExprNodeDesc> oldExprs) {
    DeferredJavaObject[] arguments = new DeferredJavaObject[exprs.size()];
    ObjectInspector[] argois = new ObjectInspector[exprs.size()];
    for (int i = 0; i < exprs.size(); i++) {
        ExprNodeDesc desc = exprs.get(i);
        if (desc instanceof ExprNodeConstantDesc) {
            ExprNodeConstantDesc constant = (ExprNodeConstantDesc) exprs.get(i);
            if (!constant.getTypeInfo().equals(oldExprs.get(i).getTypeInfo())) {
                constant = typeCast(constant, oldExprs.get(i).getTypeInfo());
                if (constant == null) {
                    return null;
                }
            }
            if (constant.getTypeInfo().getCategory() != Category.PRIMITIVE) {
                // nested complex types cannot be folded cleanly
                return null;
            }
            Object value = constant.getValue();
            PrimitiveTypeInfo pti = (PrimitiveTypeInfo) constant.getTypeInfo();
            Object writableValue = null == value ? value : PrimitiveObjectInspectorFactory.getPrimitiveJavaObjectInspector(pti).getPrimitiveWritableObject(value);
            arguments[i] = new DeferredJavaObject(writableValue);
            argois[i] = ObjectInspectorUtils.getConstantObjectInspector(constant.getWritableObjectInspector(), writableValue);
        } else if (desc instanceof ExprNodeGenericFuncDesc) {
            ExprNodeDesc evaluatedFn = foldExpr((ExprNodeGenericFuncDesc) desc);
            if (null == evaluatedFn || !(evaluatedFn instanceof ExprNodeConstantDesc)) {
                return null;
            }
            ExprNodeConstantDesc constant = (ExprNodeConstantDesc) evaluatedFn;
            if (constant.getTypeInfo().getCategory() != Category.PRIMITIVE) {
                // nested complex types cannot be folded cleanly
                return null;
            }
            Object writableValue = PrimitiveObjectInspectorFactory.getPrimitiveJavaObjectInspector((PrimitiveTypeInfo) constant.getTypeInfo()).getPrimitiveWritableObject(constant.getValue());
            arguments[i] = new DeferredJavaObject(writableValue);
            argois[i] = ObjectInspectorUtils.getConstantObjectInspector(constant.getWritableObjectInspector(), writableValue);
        } else {
            return null;
        }
    }
    try {
        ObjectInspector oi = udf.initialize(argois);
        Object o = udf.evaluate(arguments);
        if (LOG.isDebugEnabled()) {
            LOG.debug(udf.getClass().getName() + "(" + exprs + ")=" + o);
        }
        if (o == null) {
            return new ExprNodeConstantDesc(TypeInfoUtils.getTypeInfoFromObjectInspector(oi), o);
        }
        Class<?> clz = o.getClass();
        if (PrimitiveObjectInspectorUtils.isPrimitiveWritableClass(clz)) {
            PrimitiveObjectInspector poi = (PrimitiveObjectInspector) oi;
            TypeInfo typeInfo = poi.getTypeInfo();
            o = poi.getPrimitiveJavaObject(o);
            if (typeInfo.getTypeName().contains(serdeConstants.DECIMAL_TYPE_NAME) || typeInfo.getTypeName().contains(serdeConstants.VARCHAR_TYPE_NAME) || typeInfo.getTypeName().contains(serdeConstants.CHAR_TYPE_NAME)) {
                return new ExprNodeConstantDesc(typeInfo, o);
            }
        } else if (udf instanceof GenericUDFStruct && oi instanceof StandardConstantStructObjectInspector) {
            // do not fold named_struct, only struct()
            ConstantObjectInspector coi = (ConstantObjectInspector) oi;
            TypeInfo structType = TypeInfoUtils.getTypeInfoFromObjectInspector(coi);
            return new ExprNodeConstantDesc(structType, ObjectInspectorUtils.copyToStandardJavaObject(o, coi));
        } else if (!PrimitiveObjectInspectorUtils.isPrimitiveJavaClass(clz)) {
            if (LOG.isErrorEnabled()) {
                LOG.error("Unable to evaluate " + udf + ". Return value unrecoginizable.");
            }
            return null;
        } else {
        // fall through
        }
        String constStr = null;
        if (arguments.length == 1 && FunctionRegistry.isOpCast(udf)) {
            // remember original string representation of constant.
            constStr = arguments[0].get().toString();
        }
        return new ExprNodeConstantDesc(o).setFoldedFromVal(constStr);
    } catch (HiveException e) {
        LOG.error("Evaluation function " + udf.getClass() + " failed in Constant Propagation Optimizer.");
        throw new RuntimeException(e);
    }
}