/*
* Copyright 2008-2014 the original author or authors.
*
* 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 org.codehaus.groovy.transform;
import groovy.transform.InheritConstructors;
import org.codehaus.groovy.ast.ASTNode;
import org.codehaus.groovy.ast.AnnotatedNode;
import org.codehaus.groovy.ast.AnnotationNode;
import org.codehaus.groovy.ast.ClassNode;
import org.codehaus.groovy.ast.ConstructorNode;
import org.codehaus.groovy.ast.Parameter;
import org.codehaus.groovy.ast.expr.Expression;
import org.codehaus.groovy.control.CompilePhase;
import org.codehaus.groovy.control.SourceUnit;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import static org.codehaus.groovy.ast.ClassHelper.make;
import static org.codehaus.groovy.ast.tools.GeneralUtils.args;
import static org.codehaus.groovy.ast.tools.GeneralUtils.block;
import static org.codehaus.groovy.ast.tools.GeneralUtils.ctorSuperS;
import static org.codehaus.groovy.ast.tools.GeneralUtils.param;
import static org.codehaus.groovy.ast.tools.GeneralUtils.varX;
import static org.codehaus.groovy.ast.tools.GenericsUtils.correctToGenericsSpecRecurse;
import static org.codehaus.groovy.ast.tools.GenericsUtils.createGenericsSpec;
import static org.codehaus.groovy.ast.tools.GenericsUtils.extractSuperClassGenerics;
/**
* Handles generation of code for the {@code @}InheritConstructors annotation.
*
* @author Paul King
*/
@GroovyASTTransformation(phase = CompilePhase.CANONICALIZATION)
public class InheritConstructorsASTTransformation extends AbstractASTTransformation {
private static final Class MY_CLASS = InheritConstructors.class;
private static final ClassNode MY_TYPE = make(MY_CLASS);
private static final String MY_TYPE_NAME = "@" + MY_TYPE.getNameWithoutPackage();
public void visit(ASTNode[] nodes, SourceUnit source) {
init(nodes, source);
AnnotatedNode parent = (AnnotatedNode) nodes[1];
AnnotationNode node = (AnnotationNode) nodes[0];
if (!MY_TYPE.equals(node.getClassNode())) return;
if (parent instanceof ClassNode) {
processClass((ClassNode) parent);
}
}
private void processClass(ClassNode cNode) {
if (cNode.isInterface()) {
addError("Error processing interface '" + cNode.getName() +
"'. " + MY_TYPE_NAME + " only allowed for classes.", cNode);
return;
}
ClassNode sNode = cNode.getSuperClass();
List<AnnotationNode> superAnnotations = sNode.getAnnotations(MY_TYPE);
if (superAnnotations.size() == 1) {
// We need @InheritConstructors from parent classes processed first
// so force that order here. The transformation is benign on an already
// processed node so processing twice in any order won't matter bar
// a very small time penalty.
processClass(sNode);
}
for (ConstructorNode cn : sNode.getDeclaredConstructors()) {
addConstructorUnlessAlreadyExisting(cNode, cn);
}
}
private void addConstructorUnlessAlreadyExisting(ClassNode classNode, ConstructorNode consNode) {
Parameter[] origParams = consNode.getParameters();
if (consNode.isPrivate()) return;
Parameter[] params = new Parameter[origParams.length];
List<Expression> theArgs = new ArrayList<Expression>();
Map<String, ClassNode> genericsSpec = createGenericsSpec(classNode);
extractSuperClassGenerics(classNode, classNode.getSuperClass(), genericsSpec);
for (int i = 0; i < origParams.length; i++) {
Parameter p = origParams[i];
ClassNode newType = correctToGenericsSpecRecurse(genericsSpec, p.getType());
params[i] = p.hasInitialExpression() ? param(newType, p.getName(), p.getInitialExpression()) : param(newType, p.getName());
theArgs.add(varX(p.getName(), newType));
}
if (isExisting(classNode, params)) return;
classNode.addConstructor(consNode.getModifiers(), params, consNode.getExceptions(), block(ctorSuperS(args(theArgs))));
}
private boolean isExisting(ClassNode classNode, Parameter[] params) {
for (ConstructorNode consNode : classNode.getDeclaredConstructors()) {
if (matchingTypes(params, consNode.getParameters())) {
return true;
}
}
return false;
}
private boolean matchingTypes(Parameter[] params, Parameter[] existingParams) {
if (params.length != existingParams.length) return false;
for (int i = 0; i < params.length; i++) {
if (!params[i].getType().equals(existingParams[i].getType())) {
return false;
}
}
return true;
}
}