Groovy example source code file (CanonicalASTTransformation.java)

This example Groovy source code file (CanonicalASTTransformation.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Groovy tags/keywords

annotatednode, annotatednode, annotationnode, annotationnode, canonicalasttransformation, classnode, classnode, error, list, my_type_name, my_type_name, only, sourceunit, string, util

The Groovy CanonicalASTTransformation.java source code

/*
 * Copyright 2008-2011 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.Canonical;
import org.codehaus.groovy.ast.*;
import org.codehaus.groovy.ast.expr.ConstantExpression;
import org.codehaus.groovy.control.CompilePhase;
import org.codehaus.groovy.control.SourceUnit;

import java.util.List;

import static org.codehaus.groovy.transform.EqualsAndHashCodeASTTransformation.createEquals;
import static org.codehaus.groovy.transform.EqualsAndHashCodeASTTransformation.createHashCode;
import static org.codehaus.groovy.transform.ToStringASTTransformation.createToString;
import static org.codehaus.groovy.transform.ToStringASTTransformation.toStringInit;
import static org.codehaus.groovy.transform.TupleConstructorASTTransformation.createConstructor;

/**
 * Handles generation of code for the @Canonical annotation.
 *
 * @author Paulo Poiati
 * @author Paul King
 */
@GroovyASTTransformation(phase = CompilePhase.CANONICALIZATION)
public class CanonicalASTTransformation extends AbstractASTTransformation {

    static final Class MY_CLASS = Canonical.class;
    static final ClassNode MY_TYPE = ClassHelper.make(MY_CLASS);
    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 anno = (AnnotationNode) nodes[0];
        if (!MY_TYPE.equals(anno.getClassNode())) return;

        if (parent instanceof ClassNode) {
            ClassNode cNode = (ClassNode) parent;
            // TODO remove - let other validation steps pick this up
            if (hasAnnotation(cNode, ImmutableASTTransformation.MY_TYPE)) {
                addError(MY_TYPE_NAME + " class '" + cNode.getName() + "' can't also be " + ImmutableASTTransformation.MY_TYPE_NAME, parent);
            }
            checkNotInterface(cNode, MY_TYPE_NAME);
            List<String> excludes = tokenize((String) getMemberValue(anno, "excludes"));
            List<String> includes = tokenize((String) getMemberValue(anno, "includes"));
            if (includes != null && !includes.isEmpty() && excludes != null && !excludes.isEmpty()) {
                addError("Error during " + MY_TYPE_NAME + " processing: Only one of 'includes' and 'excludes' should be supplied not both.", anno);
            }
            if (!hasAnnotation(cNode, TupleConstructorASTTransformation.MY_TYPE)) {
                createConstructor(cNode, false, true, false, false, false, false, excludes, includes);
            }
            if (!hasAnnotation(cNode, EqualsAndHashCodeASTTransformation.MY_TYPE)) {
                createHashCode(cNode, false, false, false, excludes, includes);
                createEquals(cNode, false, false, true, excludes, includes);
            }
            if (!hasAnnotation(cNode, ToStringASTTransformation.MY_TYPE)) {
                toStringInit(cNode, ConstantExpression.FALSE);
                createToString(cNode, false, false, excludes, includes);
            }
        }
    }

}