/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.hadoop.hive.ql.parse;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.HashSet;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.Stack;
import org.apache.commons.lang.StringUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.hive.ql.exec.ColumnInfo;
import org.apache.hadoop.hive.ql.exec.FunctionInfo;
import org.apache.hadoop.hive.ql.exec.FunctionRegistry;
import org.apache.hadoop.hive.ql.exec.UDFArgumentException;
import org.apache.hadoop.hive.ql.exec.UDFArgumentLengthException;
import org.apache.hadoop.hive.ql.exec.UDFArgumentTypeException;
import org.apache.hadoop.hive.ql.lib.DefaultGraphWalker;
import org.apache.hadoop.hive.ql.lib.DefaultRuleDispatcher;
import org.apache.hadoop.hive.ql.lib.Dispatcher;
import org.apache.hadoop.hive.ql.lib.GraphWalker;
import org.apache.hadoop.hive.ql.lib.Node;
import org.apache.hadoop.hive.ql.lib.NodeProcessor;
import org.apache.hadoop.hive.ql.lib.NodeProcessorCtx;
import org.apache.hadoop.hive.ql.lib.Rule;
import org.apache.hadoop.hive.ql.lib.RuleRegExp;
import org.apache.hadoop.hive.ql.plan.ExprNodeColumnDesc;
import org.apache.hadoop.hive.ql.plan.ExprNodeConstantDesc;
import org.apache.hadoop.hive.ql.plan.ExprNodeDesc;
import org.apache.hadoop.hive.ql.plan.ExprNodeFieldDesc;
import org.apache.hadoop.hive.ql.plan.ExprNodeGenericFuncDesc;
import org.apache.hadoop.hive.ql.plan.ExprNodeNullDesc;
import org.apache.hadoop.hive.ql.udf.generic.GenericUDF;
import org.apache.hadoop.hive.ql.udf.generic.GenericUDFBaseCompare;
import org.apache.hadoop.hive.ql.udf.generic.GenericUDFOPEqual;
import org.apache.hadoop.hive.serde.Constants;
import org.apache.hadoop.hive.serde2.objectinspector.ObjectInspector;
import org.apache.hadoop.hive.serde2.objectinspector.ObjectInspector.Category;
import org.apache.hadoop.hive.serde2.typeinfo.ListTypeInfo;
import org.apache.hadoop.hive.serde2.typeinfo.MapTypeInfo;
import org.apache.hadoop.hive.serde2.typeinfo.PrimitiveTypeInfo;
import org.apache.hadoop.hive.serde2.typeinfo.StructTypeInfo;
import org.apache.hadoop.hive.serde2.typeinfo.TypeInfo;
import org.apache.hadoop.hive.serde2.typeinfo.TypeInfoFactory;
/**
* The Factory for creating typecheck processors. The typecheck processors are
* used to processes the syntax trees for expressions and convert them into
* expression Node Descriptor trees. They also introduce the correct conversion
* functions to do proper implicit conversion.
*/
public final class TypeCheckProcFactory {
protected static final Log LOG = LogFactory.getLog(TypeCheckProcFactory.class
.getName());
private TypeCheckProcFactory() {
// prevent instantiation
}
/**
* Function to do groupby subexpression elimination. This is called by all the
* processors initially. As an example, consider the query select a+b,
* count(1) from T group by a+b; Then a+b is already precomputed in the group
* by operators key, so we substitute a+b in the select list with the internal
* column name of the a+b expression that appears in the in input row
* resolver.
*
* @param nd
* The node that is being inspected.
* @param procCtx
* The processor context.
*
* @return exprNodeColumnDesc.
*/
public static ExprNodeDesc processGByExpr(Node nd, Object procCtx)
throws SemanticException {
// We recursively create the exprNodeDesc. Base cases: when we encounter
// a column ref, we convert that into an exprNodeColumnDesc; when we
// encounter
// a constant, we convert that into an exprNodeConstantDesc. For others we
// just
// build the exprNodeFuncDesc with recursively built children.
ASTNode expr = (ASTNode) nd;
TypeCheckCtx ctx = (TypeCheckCtx) procCtx;
RowResolver input = ctx.getInputRR();
ExprNodeDesc desc = null;
// If the current subExpression is pre-calculated, as in Group-By etc.
ColumnInfo colInfo = input.getExpression(expr);
if (colInfo != null) {
desc = new ExprNodeColumnDesc(colInfo.getType(), colInfo
.getInternalName(), colInfo.getTabAlias(), colInfo
.getIsVirtualCol());
ASTNode source = input.getExpressionSource(expr);
if (source != null) {
ctx.getUnparseTranslator().addCopyTranslation(expr, source);
}
return desc;
}
return desc;
}
public static HashMap<Node, Object> genExprNode(ASTNode expr,
TypeCheckCtx tcCtx) throws SemanticException {
// Create the walker, the rules dispatcher and the context.
// create a walker which walks the tree in a DFS manner while maintaining
// the operator stack. The dispatcher
// generates the plan from the operator tree
Map<Rule, NodeProcessor> opRules = new LinkedHashMap<Rule, NodeProcessor>();
opRules.put(new RuleRegExp("R1", HiveParser.TOK_NULL + "%"),
getNullExprProcessor());
opRules.put(new RuleRegExp("R2", HiveParser.Number + "%|" +
HiveParser.TinyintLiteral + "%|" +
HiveParser.SmallintLiteral + "%|" +
HiveParser.BigintLiteral + "%"),
getNumExprProcessor());
opRules
.put(new RuleRegExp("R3", HiveParser.Identifier + "%|"
+ HiveParser.StringLiteral + "%|" + HiveParser.TOK_CHARSETLITERAL + "%|"
+ HiveParser.TOK_STRINGLITERALSEQUENCE + "%|"
+ "%|" + HiveParser.KW_IF + "%|" + HiveParser.KW_CASE + "%|"
+ HiveParser.KW_WHEN + "%|" + HiveParser.KW_IN + "%|"
+ HiveParser.KW_ARRAY + "%|" + HiveParser.KW_MAP + "%|"
+ HiveParser.KW_STRUCT + "%"),
getStrExprProcessor());
opRules.put(new RuleRegExp("R4", HiveParser.KW_TRUE + "%|"
+ HiveParser.KW_FALSE + "%"), getBoolExprProcessor());
opRules.put(new RuleRegExp("R5", HiveParser.TOK_TABLE_OR_COL + "%"),
getColumnExprProcessor());
// The dispatcher fires the processor corresponding to the closest matching
// rule and passes the context along
Dispatcher disp = new DefaultRuleDispatcher(getDefaultExprProcessor(),
opRules, tcCtx);
GraphWalker ogw = new DefaultGraphWalker(disp);
// Create a list of topop nodes
ArrayList<Node> topNodes = new ArrayList<Node>();
topNodes.add(expr);
HashMap<Node, Object> nodeOutputs = new HashMap<Node, Object>();
ogw.startWalking(topNodes, nodeOutputs);
return nodeOutputs;
}
/**
* Processor for processing NULL expression.
*/
public static class NullExprProcessor implements NodeProcessor {
@Override
public Object process(Node nd, Stack<Node> stack, NodeProcessorCtx procCtx,
Object... nodeOutputs) throws SemanticException {
TypeCheckCtx ctx = (TypeCheckCtx) procCtx;
if (ctx.getError() != null) {
return null;
}
ExprNodeDesc desc = TypeCheckProcFactory.processGByExpr(nd, procCtx);
if (desc != null) {
return desc;
}
return new ExprNodeNullDesc();
}
}
/**
* Factory method to get NullExprProcessor.
*
* @return NullExprProcessor.
*/
public static NullExprProcessor getNullExprProcessor() {
return new NullExprProcessor();
}
/**
* Processor for processing numeric constants.
*/
public static class NumExprProcessor implements NodeProcessor {
@Override
public Object process(Node nd, Stack<Node> stack, NodeProcessorCtx procCtx,
Object... nodeOutputs) throws SemanticException {
TypeCheckCtx ctx = (TypeCheckCtx) procCtx;
if (ctx.getError() != null) {
return null;
}
ExprNodeDesc desc = TypeCheckProcFactory.processGByExpr(nd, procCtx);
if (desc != null) {
return desc;
}
Number v = null;
ASTNode expr = (ASTNode) nd;
// The expression can be any one of Double, Long and Integer. We
// try to parse the expression in that order to ensure that the
// most specific type is used for conversion.
try {
if (expr.getText().endsWith("L")) {
// Literal bigint.
v = Long.valueOf(expr.getText().substring(
0, expr.getText().length() - 1));
} else if (expr.getText().endsWith("S")) {
// Literal smallint.
v = Short.valueOf(expr.getText().substring(
0, expr.getText().length() - 1));
} else if (expr.getText().endsWith("Y")) {
// Literal tinyint.
v = Byte.valueOf(expr.getText().substring(
0, expr.getText().length() - 1));
} else {
v = Double.valueOf(expr.getText());
v = Long.valueOf(expr.getText());
v = Integer.valueOf(expr.getText());
}
} catch (NumberFormatException e) {
// do nothing here, we will throw an exception in the following block
}
if (v == null) {
throw new SemanticException(ErrorMsg.INVALID_NUMERICAL_CONSTANT
.getMsg(expr));
}
return new ExprNodeConstantDesc(v);
}
}
/**
* Factory method to get NumExprProcessor.
*
* @return NumExprProcessor.
*/
public static NumExprProcessor getNumExprProcessor() {
return new NumExprProcessor();
}
/**
* Processor for processing string constants.
*/
public static class StrExprProcessor implements NodeProcessor {
@Override
public Object process(Node nd, Stack<Node> stack, NodeProcessorCtx procCtx,
Object... nodeOutputs) throws SemanticException {
TypeCheckCtx ctx = (TypeCheckCtx) procCtx;
if (ctx.getError() != null) {
return null;
}
ExprNodeDesc desc = TypeCheckProcFactory.processGByExpr(nd, procCtx);
if (desc != null) {
return desc;
}
ASTNode expr = (ASTNode) nd;
String str = null;
switch (expr.getToken().getType()) {
case HiveParser.StringLiteral:
str = BaseSemanticAnalyzer.unescapeSQLString(expr.getText());
break;
case HiveParser.TOK_STRINGLITERALSEQUENCE:
StringBuilder sb = new StringBuilder();
for (Node n : expr.getChildren()) {
sb.append(
BaseSemanticAnalyzer.unescapeSQLString(((ASTNode)n).getText()));
}
str = sb.toString();
break;
case HiveParser.TOK_CHARSETLITERAL:
str = BaseSemanticAnalyzer.charSetString(expr.getChild(0).getText(),
expr.getChild(1).getText());
break;
default:
// HiveParser.identifier | HiveParse.KW_IF | HiveParse.KW_LEFT |
// HiveParse.KW_RIGHT
str = BaseSemanticAnalyzer.unescapeIdentifier(expr.getText());
break;
}
return new ExprNodeConstantDesc(TypeInfoFactory.stringTypeInfo, str);
}
}
/**
* Factory method to get StrExprProcessor.
*
* @return StrExprProcessor.
*/
public static StrExprProcessor getStrExprProcessor() {
return new StrExprProcessor();
}
/**
* Processor for boolean constants.
*/
public static class BoolExprProcessor implements NodeProcessor {
@Override
public Object process(Node nd, Stack<Node> stack, NodeProcessorCtx procCtx,
Object... nodeOutputs) throws SemanticException {
TypeCheckCtx ctx = (TypeCheckCtx) procCtx;
if (ctx.getError() != null) {
return null;
}
ExprNodeDesc desc = TypeCheckProcFactory.processGByExpr(nd, procCtx);
if (desc != null) {
return desc;
}
ASTNode expr = (ASTNode) nd;
Boolean bool = null;
switch (expr.getToken().getType()) {
case HiveParser.KW_TRUE:
bool = Boolean.TRUE;
break;
case HiveParser.KW_FALSE:
bool = Boolean.FALSE;
break;
default:
assert false;
}
return new ExprNodeConstantDesc(TypeInfoFactory.booleanTypeInfo, bool);
}
}
/**
* Factory method to get BoolExprProcessor.
*
* @return BoolExprProcessor.
*/
public static BoolExprProcessor getBoolExprProcessor() {
return new BoolExprProcessor();
}
/**
* Processor for table columns.
*/
public static class ColumnExprProcessor implements NodeProcessor {
@Override
public Object process(Node nd, Stack<Node> stack, NodeProcessorCtx procCtx,
Object... nodeOutputs) throws SemanticException {
TypeCheckCtx ctx = (TypeCheckCtx) procCtx;
if (ctx.getError() != null) {
return null;
}
ExprNodeDesc desc = TypeCheckProcFactory.processGByExpr(nd, procCtx);
if (desc != null) {
return desc;
}
ASTNode expr = (ASTNode) nd;
ASTNode parent = stack.size() > 1 ? (ASTNode) stack.get(stack.size() - 2) : null;
RowResolver input = ctx.getInputRR();
if (expr.getType() != HiveParser.TOK_TABLE_OR_COL) {
ctx.setError(ErrorMsg.INVALID_COLUMN.getMsg(expr), expr);
return null;
}
assert (expr.getChildCount() == 1);
String tableOrCol = BaseSemanticAnalyzer.unescapeIdentifier(expr
.getChild(0).getText());
boolean isTableAlias = input.hasTableAlias(tableOrCol);
ColumnInfo colInfo = input.get(null, tableOrCol);
if (isTableAlias) {
if (colInfo != null) {
if (parent != null && parent.getType() == HiveParser.DOT) {
// It's a table alias.
return null;
}
// It's a column.
return new ExprNodeColumnDesc(colInfo.getType(), colInfo
.getInternalName(), colInfo.getTabAlias(), colInfo
.getIsVirtualCol());
} else {
// It's a table alias.
// We will process that later in DOT.
return null;
}
} else {
if (colInfo == null) {
// It's not a column or a table alias.
if (input.getIsExprResolver()) {
ASTNode exprNode = expr;
if (!stack.empty()) {
ASTNode tmp = (ASTNode) stack.pop();
if (!stack.empty()) {
exprNode = (ASTNode) stack.peek();
}
stack.push(tmp);
}
ctx.setError(ErrorMsg.NON_KEY_EXPR_IN_GROUPBY.getMsg(exprNode), expr);
return null;
} else {
List<String> possibleColumnNames = input.getNonHiddenColumnNames(-1);
String reason = String.format("(possible column names are: %s)",
StringUtils.join(possibleColumnNames, ", "));
ctx.setError(ErrorMsg.INVALID_TABLE_OR_COLUMN.getMsg(expr.getChild(0), reason),
expr);
LOG.debug(ErrorMsg.INVALID_TABLE_OR_COLUMN.toString() + ":"
+ input.toString());
return null;
}
} else {
// It's a column.
return new ExprNodeColumnDesc(colInfo.getType(), colInfo
.getInternalName(), colInfo.getTabAlias(), colInfo
.getIsVirtualCol());
}
}
}
}
/**
* Factory method to get ColumnExprProcessor.
*
* @return ColumnExprProcessor.
*/
public static ColumnExprProcessor getColumnExprProcessor() {
return new ColumnExprProcessor();
}
/**
* The default processor for typechecking.
*/
public static class DefaultExprProcessor implements NodeProcessor {
static HashMap<Integer, String> specialUnaryOperatorTextHashMap;
static HashMap<Integer, String> specialFunctionTextHashMap;
static HashMap<Integer, String> conversionFunctionTextHashMap;
static {
specialUnaryOperatorTextHashMap = new HashMap<Integer, String>();
specialUnaryOperatorTextHashMap.put(HiveParser.PLUS, "positive");
specialUnaryOperatorTextHashMap.put(HiveParser.MINUS, "negative");
specialFunctionTextHashMap = new HashMap<Integer, String>();
specialFunctionTextHashMap.put(HiveParser.TOK_ISNULL, "isnull");
specialFunctionTextHashMap.put(HiveParser.TOK_ISNOTNULL, "isnotnull");
conversionFunctionTextHashMap = new HashMap<Integer, String>();
conversionFunctionTextHashMap.put(HiveParser.TOK_BOOLEAN,
Constants.BOOLEAN_TYPE_NAME);
conversionFunctionTextHashMap.put(HiveParser.TOK_TINYINT,
Constants.TINYINT_TYPE_NAME);
conversionFunctionTextHashMap.put(HiveParser.TOK_SMALLINT,
Constants.SMALLINT_TYPE_NAME);
conversionFunctionTextHashMap.put(HiveParser.TOK_INT,
Constants.INT_TYPE_NAME);
conversionFunctionTextHashMap.put(HiveParser.TOK_BIGINT,
Constants.BIGINT_TYPE_NAME);
conversionFunctionTextHashMap.put(HiveParser.TOK_FLOAT,
Constants.FLOAT_TYPE_NAME);
conversionFunctionTextHashMap.put(HiveParser.TOK_DOUBLE,
Constants.DOUBLE_TYPE_NAME);
conversionFunctionTextHashMap.put(HiveParser.TOK_STRING,
Constants.STRING_TYPE_NAME);
conversionFunctionTextHashMap.put(HiveParser.TOK_BINARY,
Constants.BINARY_TYPE_NAME);
conversionFunctionTextHashMap.put(HiveParser.TOK_TIMESTAMP,
Constants.TIMESTAMP_TYPE_NAME);
}
public static boolean isRedundantConversionFunction(ASTNode expr,
boolean isFunction, ArrayList<ExprNodeDesc> children) {
if (!isFunction) {
return false;
}
// children is always one less than the expr.getChildCount(), since the
// latter contains function name.
assert (children.size() == expr.getChildCount() - 1);
// conversion functions take a single parameter
if (children.size() != 1) {
return false;
}
String funcText = conversionFunctionTextHashMap.get(((ASTNode) expr
.getChild(0)).getType());
// not a conversion function
if (funcText == null) {
return false;
}
// return true when the child type and the conversion target type is the
// same
return ((PrimitiveTypeInfo) children.get(0).getTypeInfo()).getTypeName()
.equalsIgnoreCase(funcText);
}
public static String getFunctionText(ASTNode expr, boolean isFunction) {
String funcText = null;
if (!isFunction) {
// For operator, the function name is the operator text, unless it's in
// our special dictionary
if (expr.getChildCount() == 1) {
funcText = specialUnaryOperatorTextHashMap.get(expr.getType());
}
if (funcText == null) {
funcText = expr.getText();
}
} else {
// For TOK_FUNCTION, the function name is stored in the first child,
// unless it's in our
// special dictionary.
assert (expr.getChildCount() >= 1);
int funcType = ((ASTNode) expr.getChild(0)).getType();
funcText = specialFunctionTextHashMap.get(funcType);
if (funcText == null) {
funcText = conversionFunctionTextHashMap.get(funcType);
}
if (funcText == null) {
funcText = ((ASTNode) expr.getChild(0)).getText();
}
}
return BaseSemanticAnalyzer.unescapeIdentifier(funcText);
}
/**
* This function create an ExprNodeDesc for a UDF function given the
* children (arguments). It will insert implicit type conversion functions
* if necessary.
*
* @throws UDFArgumentException
*/
public static ExprNodeDesc getFuncExprNodeDesc(String udfName,
ExprNodeDesc... children) throws UDFArgumentException {
FunctionInfo fi = FunctionRegistry.getFunctionInfo(udfName);
if (fi == null) {
throw new UDFArgumentException(udfName + " not found.");
}
GenericUDF genericUDF = fi.getGenericUDF();
if (genericUDF == null) {
throw new UDFArgumentException(udfName
+ " is an aggregation function or a table function.");
}
List<ExprNodeDesc> childrenList = new ArrayList<ExprNodeDesc>(children.length);
childrenList.addAll(Arrays.asList(children));
return ExprNodeGenericFuncDesc.newInstance(genericUDF, childrenList);
}
static ExprNodeDesc getXpathOrFuncExprNodeDesc(ASTNode expr,
boolean isFunction, ArrayList<ExprNodeDesc> children, TypeCheckCtx ctx)
throws SemanticException, UDFArgumentException {
// return the child directly if the conversion is redundant.
if (isRedundantConversionFunction(expr, isFunction, children)) {
assert (children.size() == 1);
assert (children.get(0) != null);
return children.get(0);
}
String funcText = getFunctionText(expr, isFunction);
ExprNodeDesc desc;
if (funcText.equals(".")) {
// "." : FIELD Expression
assert (children.size() == 2);
// Only allow constant field name for now
assert (children.get(1) instanceof ExprNodeConstantDesc);
ExprNodeDesc object = children.get(0);
ExprNodeConstantDesc fieldName = (ExprNodeConstantDesc) children.get(1);
assert (fieldName.getValue() instanceof String);
// Calculate result TypeInfo
String fieldNameString = (String) fieldName.getValue();
TypeInfo objectTypeInfo = object.getTypeInfo();
// Allow accessing a field of list element structs directly from a list
boolean isList = (object.getTypeInfo().getCategory() == ObjectInspector.Category.LIST);
if (isList) {
objectTypeInfo = ((ListTypeInfo) objectTypeInfo)
.getListElementTypeInfo();
}
if (objectTypeInfo.getCategory() != Category.STRUCT) {
throw new SemanticException(ErrorMsg.INVALID_DOT.getMsg(expr));
}
TypeInfo t = ((StructTypeInfo) objectTypeInfo)
.getStructFieldTypeInfo(fieldNameString);
if (isList) {
t = TypeInfoFactory.getListTypeInfo(t);
}
desc = new ExprNodeFieldDesc(t, children.get(0), fieldNameString,
isList);
} else if (funcText.equals("[")) {
// "[]" : LSQUARE/INDEX Expression
assert (children.size() == 2);
// Check whether this is a list or a map
TypeInfo myt = children.get(0).getTypeInfo();
if (myt.getCategory() == Category.LIST) {
// Only allow integer index for now
if (!(children.get(1) instanceof ExprNodeConstantDesc)
|| !(((ExprNodeConstantDesc) children.get(1)).getTypeInfo()
.equals(TypeInfoFactory.intTypeInfo))) {
throw new SemanticException(SemanticAnalyzer.generateErrorMessage(
expr,
ErrorMsg.INVALID_ARRAYINDEX_CONSTANT.getMsg()));
}
// Calculate TypeInfo
TypeInfo t = ((ListTypeInfo) myt).getListElementTypeInfo();
desc = new ExprNodeGenericFuncDesc(t, FunctionRegistry
.getGenericUDFForIndex(), children);
} else if (myt.getCategory() == Category.MAP) {
// Only allow constant map key for now
if (!(children.get(1) instanceof ExprNodeConstantDesc)) {
throw new SemanticException(SemanticAnalyzer.generateErrorMessage(
expr,
ErrorMsg.INVALID_MAPINDEX_CONSTANT.getMsg()));
}
if (!(((ExprNodeConstantDesc) children.get(1)).getTypeInfo()
.equals(((MapTypeInfo) myt).getMapKeyTypeInfo()))) {
throw new SemanticException(ErrorMsg.INVALID_MAPINDEX_TYPE
.getMsg(expr));
}
// Calculate TypeInfo
TypeInfo t = ((MapTypeInfo) myt).getMapValueTypeInfo();
desc = new ExprNodeGenericFuncDesc(t, FunctionRegistry
.getGenericUDFForIndex(), children);
} else {
throw new SemanticException(ErrorMsg.NON_COLLECTION_TYPE.getMsg(expr,
myt.getTypeName()));
}
} else {
// other operators or functions
FunctionInfo fi = FunctionRegistry.getFunctionInfo(funcText);
if (fi == null) {
if (isFunction) {
throw new SemanticException(ErrorMsg.INVALID_FUNCTION
.getMsg((ASTNode) expr.getChild(0)));
} else {
throw new SemanticException(ErrorMsg.INVALID_FUNCTION.getMsg(expr));
}
}
if (!fi.isNative()) {
ctx.getUnparseTranslator().addIdentifierTranslation(
(ASTNode) expr.getChild(0));
}
// Detect UDTF's in nested SELECT, GROUP BY, etc as they aren't
// supported
if (fi.getGenericUDTF() != null) {
throw new SemanticException(ErrorMsg.UDTF_INVALID_LOCATION.getMsg());
}
if (!ctx.getAllowStatefulFunctions() && (fi.getGenericUDF() != null)) {
if (FunctionRegistry.isStateful(fi.getGenericUDF())) {
throw new SemanticException(
ErrorMsg.UDF_STATEFUL_INVALID_LOCATION.getMsg());
}
}
// Try to infer the type of the constant only if there are two
// nodes, one of them is column and the other is numeric const
if (fi.getGenericUDF() instanceof GenericUDFBaseCompare
&& children.size() == 2
&& ((children.get(0) instanceof ExprNodeConstantDesc
&& children.get(1) instanceof ExprNodeColumnDesc)
|| (children.get(0) instanceof ExprNodeColumnDesc
&& children.get(1) instanceof ExprNodeConstantDesc))) {
int constIdx =
children.get(0) instanceof ExprNodeConstantDesc ? 0 : 1;
Set<String> inferTypes = new HashSet<String>(Arrays.asList(
Constants.TINYINT_TYPE_NAME.toLowerCase(),
Constants.SMALLINT_TYPE_NAME.toLowerCase(),
Constants.INT_TYPE_NAME.toLowerCase(),
Constants.BIGINT_TYPE_NAME.toLowerCase(),
Constants.FLOAT_TYPE_NAME.toLowerCase(),
Constants.DOUBLE_TYPE_NAME.toLowerCase(),
Constants.STRING_TYPE_NAME.toLowerCase()
));
String constType = children.get(constIdx).getTypeString().toLowerCase();
String columnType = children.get(1 - constIdx).getTypeString().toLowerCase();
if (inferTypes.contains(constType) && inferTypes.contains(columnType)
&& !columnType.equalsIgnoreCase(constType)) {
String constValue =
((ExprNodeConstantDesc) children.get(constIdx)).getValue().toString();
boolean triedDouble = false;
Number value = null;
try {
if (columnType.equalsIgnoreCase(Constants.TINYINT_TYPE_NAME)) {
value = new Byte(constValue);
} else if (columnType.equalsIgnoreCase(Constants.SMALLINT_TYPE_NAME)) {
value = new Short(constValue);
} else if (columnType.equalsIgnoreCase(Constants.INT_TYPE_NAME)) {
value = new Integer(constValue);
} else if (columnType.equalsIgnoreCase(Constants.BIGINT_TYPE_NAME)) {
value = new Long(constValue);
} else if (columnType.equalsIgnoreCase(Constants.FLOAT_TYPE_NAME)) {
value = new Float(constValue);
} else if (columnType.equalsIgnoreCase(Constants.DOUBLE_TYPE_NAME)
|| (columnType.equalsIgnoreCase(Constants.STRING_TYPE_NAME)
&& !constType.equalsIgnoreCase(Constants.BIGINT_TYPE_NAME))) {
// no smart inference for queries like "str_col = bigint_const"
triedDouble = true;
value = new Double(constValue);
}
} catch (NumberFormatException nfe) {
// this exception suggests the precise type inference did not succeed
// we'll try again to convert it to double
// however, if we already tried this, or the column is NUMBER type and
// the operator is EQUAL, return false due to the type mismatch
if (triedDouble ||
(fi.getGenericUDF() instanceof GenericUDFOPEqual
&& !columnType.equals(Constants.STRING_TYPE_NAME))) {
return new ExprNodeConstantDesc(false);
}
try {
value = new Double(constValue);
} catch (NumberFormatException ex) {
return new ExprNodeConstantDesc(false);
}
}
if (value != null) {
children.set(constIdx, new ExprNodeConstantDesc(value));
}
}
}
desc = ExprNodeGenericFuncDesc.newInstance(fi.getGenericUDF(), children);
}
// UDFOPPositive is a no-op.
// However, we still create it, and then remove it here, to make sure we
// only allow
// "+" for numeric types.
if (FunctionRegistry.isOpPositive(desc)) {
assert (desc.getChildren().size() == 1);
desc = desc.getChildren().get(0);
}
assert (desc != null);
return desc;
}
/**
* Returns true if des is a descendant of ans (ancestor)
*/
private boolean isDescendant(Node ans, Node des) {
if (ans.getChildren() == null) {
return false;
}
for (Node c : ans.getChildren()) {
if (c == des) {
return true;
}
if (isDescendant(c, des)) {
return true;
}
}
return false;
}
@Override
public Object process(Node nd, Stack<Node> stack, NodeProcessorCtx procCtx,
Object... nodeOutputs) throws SemanticException {
TypeCheckCtx ctx = (TypeCheckCtx) procCtx;
ExprNodeDesc desc = TypeCheckProcFactory.processGByExpr(nd, procCtx);
if (desc != null) {
// Here we know nd represents a group by expression.
// During the DFS traversal of the AST, a descendant of nd likely set an
// error because a sub-tree of nd is unlikely to also be a group by
// expression. For example, in a query such as
// SELECT *concat(key)* FROM src GROUP BY concat(key), 'key' will be
// processed before 'concat(key)' and since 'key' is not a group by
// expression, an error will be set in ctx by ColumnExprProcessor.
// We can clear the global error when we see that it was set in a
// descendant node of a group by expression because
// processGByExpr() returns a ExprNodeDesc that effectively ignores
// its children. Although the error can be set multiple times by
// descendant nodes, DFS traversal ensures that the error only needs to
// be cleared once. Also, for a case like
// SELECT concat(value, concat(value))... the logic still works as the
// error is only set with the first 'value'; all node pocessors quit
// early if the global error is set.
if (isDescendant(nd, ctx.getErrorSrcNode())) {
ctx.setError(null, null);
}
return desc;
}
if (ctx.getError() != null) {
return null;
}
ASTNode expr = (ASTNode) nd;
// If the first child is a TOK_TABLE_OR_COL, and nodeOutput[0] is NULL,
// and the operator is a DOT, then it's a table column reference.
if (expr.getType() == HiveParser.DOT
&& expr.getChild(0).getType() == HiveParser.TOK_TABLE_OR_COL
&& nodeOutputs[0] == null) {
RowResolver input = ctx.getInputRR();
String tableAlias = BaseSemanticAnalyzer.unescapeIdentifier(expr
.getChild(0).getChild(0).getText());
// NOTE: tableAlias must be a valid non-ambiguous table alias,
// because we've checked that in TOK_TABLE_OR_COL's process method.
ColumnInfo colInfo = input.get(tableAlias,
((ExprNodeConstantDesc) nodeOutputs[1]).getValue().toString());
if (colInfo == null) {
ctx.setError(ErrorMsg.INVALID_COLUMN.getMsg(expr.getChild(1)), expr);
return null;
}
return new ExprNodeColumnDesc(colInfo.getType(), colInfo
.getInternalName(), colInfo.getTabAlias(), colInfo
.getIsVirtualCol());
}
// Return nulls for conversion operators
if (conversionFunctionTextHashMap.keySet().contains(expr.getType())
|| specialFunctionTextHashMap.keySet().contains(expr.getType())
|| expr.getToken().getType() == HiveParser.CharSetName
|| expr.getToken().getType() == HiveParser.CharSetLiteral) {
return null;
}
boolean isFunction = (expr.getType() == HiveParser.TOK_FUNCTION);
// Create all children
int childrenBegin = (isFunction ? 1 : 0);
ArrayList<ExprNodeDesc> children = new ArrayList<ExprNodeDesc>(expr
.getChildCount()
- childrenBegin);
for (int ci = childrenBegin; ci < expr.getChildCount(); ci++) {
children.add((ExprNodeDesc) nodeOutputs[ci]);
}
// If any of the children contains null, then return a null
// this is a hack for now to handle the group by case
if (children.contains(null)) {
return null;
}
// Create function desc
try {
return getXpathOrFuncExprNodeDesc(expr, isFunction, children, ctx);
} catch (UDFArgumentTypeException e) {
throw new SemanticException(ErrorMsg.INVALID_ARGUMENT_TYPE.getMsg(expr
.getChild(childrenBegin + e.getArgumentId()), e.getMessage()));
} catch (UDFArgumentLengthException e) {
throw new SemanticException(ErrorMsg.INVALID_ARGUMENT_LENGTH.getMsg(
expr, e.getMessage()));
} catch (UDFArgumentException e) {
throw new SemanticException(ErrorMsg.INVALID_ARGUMENT.getMsg(expr, e
.getMessage()));
}
}
}
/**
* Factory method to get DefaultExprProcessor.
*
* @return DefaultExprProcessor.
*/
public static DefaultExprProcessor getDefaultExprProcessor() {
return new DefaultExprProcessor();
}
}