com.blazebit.persistence.parser.expression.ExpressionOptimizer Maven / Gradle / Ivy
/*
* Copyright 2014 - 2020 Blazebit.
*
* Licensed 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 com.blazebit.persistence.parser.expression;
import com.blazebit.persistence.parser.predicate.BetweenPredicate;
import com.blazebit.persistence.parser.predicate.BinaryExpressionPredicate;
import com.blazebit.persistence.parser.predicate.BooleanLiteral;
import com.blazebit.persistence.parser.predicate.CompoundPredicate;
import com.blazebit.persistence.parser.predicate.EqPredicate;
import com.blazebit.persistence.parser.predicate.ExistsPredicate;
import com.blazebit.persistence.parser.predicate.GePredicate;
import com.blazebit.persistence.parser.predicate.GtPredicate;
import com.blazebit.persistence.parser.predicate.InPredicate;
import com.blazebit.persistence.parser.predicate.IsEmptyPredicate;
import com.blazebit.persistence.parser.predicate.IsNullPredicate;
import com.blazebit.persistence.parser.predicate.LePredicate;
import com.blazebit.persistence.parser.predicate.LikePredicate;
import com.blazebit.persistence.parser.predicate.LtPredicate;
import com.blazebit.persistence.parser.predicate.MemberOfPredicate;
import com.blazebit.persistence.parser.predicate.Predicate;
import com.blazebit.persistence.parser.predicate.UnaryExpressionPredicate;
import java.util.List;
/**
*
* @author Moritz Becker
* @since 1.2.0
*/
public class ExpressionOptimizer implements Expression.ResultVisitor {
@Override
public Expression visit(ArithmeticFactor expression) {
if (expression.getExpression() instanceof ArithmeticFactor) {
ArithmeticFactor subFactor = (ArithmeticFactor) expression.getExpression();
boolean invert = expression.isInvertSignum();
boolean subInvert = subFactor.isInvertSignum();
if (invert && subInvert) {
subFactor.setInvertSignum(false);
} else if (invert && !subInvert) {
subFactor.setInvertSignum(true);
}
return subFactor.accept(this);
} else if (expression.getExpression() instanceof NumericLiteral && !expression.isInvertSignum()) {
return expression.getExpression();
} else {
expression.setExpression(expression.getExpression().accept(this));
return expression;
}
}
@Override
public Expression visit(CompoundPredicate predicate) {
if (predicate.getChildren().size() == 1) {
Predicate subPredicate = predicate.getChildren().get(0);
if (predicate.isNegated()) {
subPredicate.negate();
}
return subPredicate.accept(this);
} else {
boolean negate = predicate.isNegated();
if (negate) {
predicate = new CompoundPredicate(predicate.getOperator().invert(), predicate.getChildren());
}
for (int i = 0; i < predicate.getChildren().size(); i++) {
Predicate child = predicate.getChildren().get(i);
if (negate) {
child.negate();
}
predicate.getChildren().set(i, (Predicate) child.accept(this));
}
return predicate;
}
}
// The rest is just inplace replacement
@Override
public Expression visit(PathExpression expression) {
for (int i = 0; i < expression.getExpressions().size(); i++) {
expression.getExpressions().set(i, (PathElementExpression) expression.getExpressions().get(i).accept(this));
}
return expression;
}
@Override
public Expression visit(TreatExpression expression) {
expression.getExpression().accept(this);
return expression;
}
@Override
public Expression visit(PropertyExpression expression) {
return expression;
}
@Override
public Expression visit(ParameterExpression expression) {
return expression;
}
@Override
public Expression visit(ListIndexExpression expression) {
expression.setPath((PathExpression) expression.getPath().accept(this));
return expression;
}
@Override
public Expression visit(MapEntryExpression expression) {
expression.setPath((PathExpression) expression.getPath().accept(this));
return expression;
}
@Override
public Expression visit(MapKeyExpression expression) {
expression.setPath((PathExpression) expression.getPath().accept(this));
return expression;
}
@Override
public Expression visit(MapValueExpression expression) {
expression.setPath((PathExpression) expression.getPath().accept(this));
return expression;
}
@Override
public Expression visit(ArrayExpression expression) {
return new ArrayExpression(expression.getBase(), expression.getIndex().accept(this));
}
@Override
public Expression visit(NullExpression expression) {
return expression;
}
@Override
public Expression visit(SubqueryExpression expression) {
return expression;
}
@Override
public Expression visit(FunctionExpression expression) {
List expressions = expression.getExpressions();
int size = expressions.size();
for (int i = 0; i < size; i++) {
expressions.set(i, expressions.get(i).accept(this));
}
WindowDefinition windowDefinition = expression.getWindowDefinition();
if (windowDefinition != null) {
Predicate filterPredicate = windowDefinition.getFilterPredicate();
if (filterPredicate != null) {
windowDefinition.setFilterPredicate((Predicate) filterPredicate.accept(this));
}
List partitionExpressions = windowDefinition.getPartitionExpressions();
size = partitionExpressions.size();
for (int i = 0; i < size; i++) {
partitionExpressions.set(i, partitionExpressions.get(i).accept(this));
}
List orderByExpressions = windowDefinition.getOrderByExpressions();
size = orderByExpressions.size();
for (int i = 0; i < size; i++) {
orderByExpressions.get(i).setExpression(orderByExpressions.get(i).getExpression().accept(this));
}
Expression frameStartExpression = windowDefinition.getFrameStartExpression();
if (frameStartExpression != null) {
windowDefinition.setFrameStartExpression(frameStartExpression.accept(this));
}
Expression frameEndExpression = windowDefinition.getFrameEndExpression();
if (frameEndExpression != null) {
windowDefinition.setFrameEndExpression(frameEndExpression.accept(this));
}
}
return expression;
}
@Override
public Expression visit(TypeFunctionExpression expression) {
return visit((FunctionExpression) expression);
}
@Override
public Expression visit(TrimExpression expression) {
expression.getTrimSource().accept(this);
return expression;
}
@Override
public Expression visit(WhenClauseExpression expression) {
return new WhenClauseExpression(expression.getCondition().accept(this), expression.getResult().accept(this));
}
@Override
public Expression visit(GeneralCaseExpression expression) {
for (int i = 0; i < expression.getWhenClauses().size(); i++) {
expression.getWhenClauses().set(i, (WhenClauseExpression) expression.getWhenClauses().get(i).accept(this));
}
if (expression.getDefaultExpr() != null) {
expression.setDefaultExpr(expression.getDefaultExpr().accept(this));
}
return expression;
}
@Override
public Expression visit(SimpleCaseExpression expression) {
expression = (SimpleCaseExpression) visit((GeneralCaseExpression) expression);
return new SimpleCaseExpression(expression.getCaseOperand().accept(this), expression.getWhenClauses(), expression.getDefaultExpr());
}
@Override
public Expression visit(ArithmeticExpression expression) {
expression.setLeft(expression.getLeft().accept(this));
expression.setRight(expression.getRight().accept(this));
return expression;
}
@Override
public Expression visit(NumericLiteral expression) {
return expression;
}
@Override
public Expression visit(StringLiteral expression) {
return expression;
}
@Override
public Expression visit(DateLiteral expression) {
return expression;
}
@Override
public Expression visit(TimeLiteral expression) {
return expression;
}
@Override
public Expression visit(TimestampLiteral expression) {
return expression;
}
@Override
public Expression visit(EnumLiteral expression) {
return expression;
}
@Override
public Expression visit(EntityLiteral expression) {
return expression;
}
@Override
public Expression visit(EqPredicate predicate) {
visitBinaryExpressionPredicate(predicate);
return predicate;
}
@Override
public Expression visit(IsNullPredicate predicate) {
visitUnaryExpressionPredicate(predicate);
return predicate;
}
@Override
public Expression visit(IsEmptyPredicate predicate) {
visitUnaryExpressionPredicate(predicate);
return predicate;
}
@Override
public Expression visit(MemberOfPredicate predicate) {
visitBinaryExpressionPredicate(predicate);
return predicate;
}
@Override
public Expression visit(LikePredicate predicate) {
visitBinaryExpressionPredicate(predicate);
return predicate;
}
@Override
public Expression visit(BetweenPredicate predicate) {
predicate.setLeft(predicate.getLeft().accept(this));
predicate.setStart(predicate.getStart().accept(this));
predicate.setEnd(predicate.getEnd().accept(this));
return predicate;
}
@Override
public Expression visit(InPredicate predicate) {
predicate.setLeft(predicate.getLeft().accept(this));
List right = predicate.getRight();
for (int i = 0; i < right.size(); i++) {
right.set(i, right.get(i).accept(this));
}
return predicate;
}
@Override
public Expression visit(GtPredicate predicate) {
visitBinaryExpressionPredicate(predicate);
return predicate;
}
@Override
public Expression visit(GePredicate predicate) {
visitBinaryExpressionPredicate(predicate);
return predicate;
}
@Override
public Expression visit(LtPredicate predicate) {
visitBinaryExpressionPredicate(predicate);
return predicate;
}
@Override
public Expression visit(LePredicate predicate) {
visitBinaryExpressionPredicate(predicate);
return predicate;
}
@Override
public Expression visit(ExistsPredicate predicate) {
visitUnaryExpressionPredicate(predicate);
return predicate;
}
@Override
public Expression visit(BooleanLiteral predicate) {
return predicate;
}
private void visitBinaryExpressionPredicate(BinaryExpressionPredicate predicate) {
predicate.setLeft(predicate.getLeft().accept(this));
predicate.setRight(predicate.getRight().accept(this));
}
private void visitUnaryExpressionPredicate(UnaryExpressionPredicate predicate) {
predicate.setExpression(predicate.getExpression().accept(this));
}
}