/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* Copyright (c) 2008-2011, Red Hat Inc. or third-party contributors as
* indicated by the @author tags or express copyright attribution
* statements applied by the authors. All third-party contributions are
* distributed under license by Red Hat Inc.
*
* This copyrighted material is made available to anyone wishing to use, modify,
* copy, or redistribute it subject to the terms and conditions of the GNU
* Lesser General Public License, as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
* for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this distribution; if not, write to:
* Free Software Foundation, Inc.
* 51 Franklin Street, Fifth Floor
* Boston, MA 02110-1301 USA
*/
package org.hibernate.hql.internal.ast.tree;
import antlr.SemanticException;
import antlr.collections.AST;
import org.hibernate.HibernateException;
import org.hibernate.TypeMismatchException;
import org.hibernate.engine.spi.SessionFactoryImplementor;
import org.hibernate.hql.internal.antlr.HqlSqlTokenTypes;
import org.hibernate.internal.util.StringHelper;
import org.hibernate.param.ParameterSpecification;
import org.hibernate.type.OneToOneType;
import org.hibernate.type.StandardBasicTypes;
import org.hibernate.type.Type;
/**
* Contract for nodes representing binary operators.
*
* @author Steve Ebersole
*/
public class BinaryLogicOperatorNode extends HqlSqlWalkerNode implements BinaryOperatorNode {
/**
* Performs the operator node initialization by seeking out any parameter
* nodes and setting their expected type, if possible.
*/
public void initialize() throws SemanticException {
Node lhs = getLeftHandOperand();
if ( lhs == null ) {
throw new SemanticException( "left-hand operand of a binary operator was null" );
}
Node rhs = getRightHandOperand();
if ( rhs == null ) {
throw new SemanticException( "right-hand operand of a binary operator was null" );
}
Type lhsType = extractDataType( lhs );
Type rhsType = extractDataType( rhs );
if ( lhsType == null ) {
lhsType = rhsType;
}
if ( rhsType == null ) {
rhsType = lhsType;
}
if ( ExpectedTypeAwareNode.class.isAssignableFrom( lhs.getClass() ) ) {
( ( ExpectedTypeAwareNode ) lhs ).setExpectedType( rhsType );
}
if ( ExpectedTypeAwareNode.class.isAssignableFrom( rhs.getClass() ) ) {
( ( ExpectedTypeAwareNode ) rhs ).setExpectedType( lhsType );
}
mutateRowValueConstructorSyntaxesIfNecessary( lhsType, rhsType );
}
protected final void mutateRowValueConstructorSyntaxesIfNecessary(Type lhsType, Type rhsType) {
// TODO : this really needs to be delayed until after we definitively know all node types
// where this is currently a problem is parameters for which where we cannot unequivocally
// resolve an expected type
SessionFactoryImplementor sessionFactory = getSessionFactoryHelper().getFactory();
if ( lhsType != null && rhsType != null ) {
int lhsColumnSpan = getColumnSpan( lhsType, sessionFactory );
if ( lhsColumnSpan != getColumnSpan( rhsType, sessionFactory ) ) {
throw new TypeMismatchException(
"left and right hand sides of a binary logic operator were incompatibile [" +
lhsType.getName() + " : "+ rhsType.getName() + "]"
);
}
if ( lhsColumnSpan > 1 ) {
// for dialects which are known to not support ANSI-SQL row-value-constructor syntax,
// we should mutate the tree.
if ( !sessionFactory.getDialect().supportsRowValueConstructorSyntax() ) {
mutateRowValueConstructorSyntax( lhsColumnSpan );
}
}
}
}
private int getColumnSpan(Type type, SessionFactoryImplementor sfi) {
int columnSpan = type.getColumnSpan( sfi );
if ( columnSpan == 0 && type instanceof OneToOneType ) {
columnSpan = ( ( OneToOneType ) type ).getIdentifierOrUniqueKeyType( sfi ).getColumnSpan( sfi );
}
return columnSpan;
}
/**
* Mutate the subtree relating to a row-value-constructor to instead use
* a series of ANDed predicates. This allows multi-column type comparisons
* and explicit row-value-constructor syntax even on databases which do
* not support row-value-constructor.
* <p/>
* For example, here we'd mutate "... where (col1, col2) = ('val1', 'val2) ..." to
* "... where col1 = 'val1' and col2 = 'val2' ..."
*
* @param valueElements The number of elements in the row value constructor list.
*/
private void mutateRowValueConstructorSyntax(int valueElements) {
// mutation depends on the types of nodes involved...
int comparisonType = getType();
String comparisonText = getText();
setType( HqlSqlTokenTypes.AND );
setText( "AND" );
String[] lhsElementTexts = extractMutationTexts( getLeftHandOperand(), valueElements );
String[] rhsElementTexts = extractMutationTexts( getRightHandOperand(), valueElements );
ParameterSpecification lhsEmbeddedCompositeParameterSpecification =
getLeftHandOperand() == null || ( !ParameterNode.class.isInstance( getLeftHandOperand() ) )
? null
: ( ( ParameterNode ) getLeftHandOperand() ).getHqlParameterSpecification();
ParameterSpecification rhsEmbeddedCompositeParameterSpecification =
getRightHandOperand() == null || ( !ParameterNode.class.isInstance( getRightHandOperand() ) )
? null
: ( ( ParameterNode ) getRightHandOperand() ).getHqlParameterSpecification();
translate( valueElements, comparisonType, comparisonText,
lhsElementTexts, rhsElementTexts,
lhsEmbeddedCompositeParameterSpecification,
rhsEmbeddedCompositeParameterSpecification, this );
}
protected void translate( int valueElements, int comparisonType,
String comparisonText, String[] lhsElementTexts,
String[] rhsElementTexts,
ParameterSpecification lhsEmbeddedCompositeParameterSpecification,
ParameterSpecification rhsEmbeddedCompositeParameterSpecification,
AST container ) {
for ( int i = valueElements - 1; i > 0; i-- ) {
if ( i == 1 ) {
AST op1 = getASTFactory().create( comparisonType, comparisonText );
AST lhs1 = getASTFactory().create( HqlSqlTokenTypes.SQL_TOKEN, lhsElementTexts[0] );
AST rhs1 = getASTFactory().create( HqlSqlTokenTypes.SQL_TOKEN, rhsElementTexts[0] );
op1.setFirstChild( lhs1 );
lhs1.setNextSibling( rhs1 );
container.setFirstChild( op1 );
AST op2 = getASTFactory().create( comparisonType, comparisonText );
AST lhs2 = getASTFactory().create( HqlSqlTokenTypes.SQL_TOKEN, lhsElementTexts[1] );
AST rhs2 = getASTFactory().create( HqlSqlTokenTypes.SQL_TOKEN, rhsElementTexts[1] );
op2.setFirstChild( lhs2 );
lhs2.setNextSibling( rhs2 );
op1.setNextSibling( op2 );
// "pass along" our initial embedded parameter node(s) to the first generated
// sql fragment so that it can be handled later for parameter binding...
SqlFragment fragment = ( SqlFragment ) lhs1;
if ( lhsEmbeddedCompositeParameterSpecification != null ) {
fragment.addEmbeddedParameter( lhsEmbeddedCompositeParameterSpecification );
}
if ( rhsEmbeddedCompositeParameterSpecification != null ) {
fragment.addEmbeddedParameter( rhsEmbeddedCompositeParameterSpecification );
}
}
else {
AST op = getASTFactory().create( comparisonType, comparisonText );
AST lhs = getASTFactory().create( HqlSqlTokenTypes.SQL_TOKEN, lhsElementTexts[i] );
AST rhs = getASTFactory().create( HqlSqlTokenTypes.SQL_TOKEN, rhsElementTexts[i] );
op.setFirstChild( lhs );
lhs.setNextSibling( rhs );
AST newContainer = getASTFactory().create( HqlSqlTokenTypes.AND, "AND" );
container.setFirstChild( newContainer );
newContainer.setNextSibling( op );
container = newContainer;
}
}
}
protected static String[] extractMutationTexts(Node operand, int count) {
if ( operand instanceof ParameterNode ) {
String[] rtn = new String[count];
for ( int i = 0; i < count; i++ ) {
rtn[i] = "?";
}
return rtn;
}
else if ( operand.getType() == HqlSqlTokenTypes.VECTOR_EXPR ) {
String[] rtn = new String[ operand.getNumberOfChildren() ];
int x = 0;
AST node = operand.getFirstChild();
while ( node != null ) {
rtn[ x++ ] = node.getText();
node = node.getNextSibling();
}
return rtn;
}
else if ( operand instanceof SqlNode ) {
String nodeText = operand.getText();
if ( nodeText.startsWith( "(" ) ) {
nodeText = nodeText.substring( 1 );
}
if ( nodeText.endsWith( ")" ) ) {
nodeText = nodeText.substring( 0, nodeText.length() - 1 );
}
String[] splits = StringHelper.split( ", ", nodeText );
if ( count != splits.length ) {
throw new HibernateException( "SqlNode's text did not reference expected number of columns" );
}
return splits;
}
else {
throw new HibernateException( "dont know how to extract row value elements from node : " + operand );
}
}
protected Type extractDataType(Node operand) {
Type type = null;
if ( operand instanceof SqlNode ) {
type = ( ( SqlNode ) operand ).getDataType();
}
if ( type == null && operand instanceof ExpectedTypeAwareNode ) {
type = ( ( ExpectedTypeAwareNode ) operand ).getExpectedType();
}
return type;
}
@Override
public Type getDataType() {
// logic operators by definition resolve to booleans
return StandardBasicTypes.BOOLEAN;
}
/**
* Retrieves the left-hand operand of the operator.
*
* @return The left-hand operand
*/
public Node getLeftHandOperand() {
return ( Node ) getFirstChild();
}
/**
* Retrieves the right-hand operand of the operator.
*
* @return The right-hand operand
*/
public Node getRightHandOperand() {
return ( Node ) getFirstChild().getNextSibling();
}
}