/**
* 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.codehaus.groovy.transform.sc.transformers;
import org.codehaus.groovy.ast.ClassHelper;
import org.codehaus.groovy.ast.ClassNode;
import org.codehaus.groovy.ast.expr.ArrayExpression;
import org.codehaus.groovy.ast.expr.CastExpression;
import org.codehaus.groovy.ast.expr.ConstantExpression;
import org.codehaus.groovy.ast.expr.Expression;
import org.codehaus.groovy.ast.expr.ListExpression;
import org.codehaus.groovy.transform.stc.StaticTypeCheckingSupport;
public class CastExpressionOptimizer {
private final StaticCompilationTransformer transformer;
public CastExpressionOptimizer(StaticCompilationTransformer staticCompilationTransformer) {
transformer = staticCompilationTransformer;
}
public Expression transformCastExpression(final CastExpression cast) {
if (cast.isCoerce()) {
Expression expression = cast.getExpression();
ClassNode exprInferredType = transformer.getTypeChooser().resolveType(expression, transformer.getClassNode());
ClassNode castType = cast.getType();
if (castType.isArray() && expression instanceof ListExpression) {
ArrayExpression arrayExpression = new ArrayExpression(castType.getComponentType(), ((ListExpression) expression).getExpressions());
arrayExpression.setSourcePosition(cast);
return transformer.transform(arrayExpression);
}
if (isOptimizable(exprInferredType, castType)) {
// coerce is not needed
CastExpression trn = new CastExpression(castType, transformer.transform(expression));
trn.setSourcePosition(cast);
trn.copyNodeMetaData(cast);
return trn;
}
} else if (ClassHelper.char_TYPE.equals(cast.getType())) {
Expression expression = cast.getExpression();
if (expression instanceof ConstantExpression) {
ConstantExpression ce = (ConstantExpression) expression;
if (ClassHelper.STRING_TYPE.equals(ce.getType())) {
String val = (String) ce.getValue();
if (val!=null && val.length()==1) {
ConstantExpression result = new ConstantExpression(val.charAt(0),true);
result.setSourcePosition(cast);
return result;
}
}
}
}
return transformer.superTransform(cast);
}
private boolean isOptimizable(final ClassNode exprInferredType, final ClassNode castType) {
if (StaticTypeCheckingSupport.implementsInterfaceOrIsSubclassOf(exprInferredType, castType)) {
return true;
}
if (ClassHelper.isPrimitiveType(exprInferredType) && ClassHelper.isPrimitiveType(castType)) {
return true;
}
return false;
}
}