org.codehaus.groovy.transform.ASTTransformation Maven / Gradle / Ivy

/*
 * Copyright 2008 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 org.codehaus.groovy.ast.ASTNode;
import org.codehaus.groovy.control.SourceUnit;

/**
 * This class is instantiated and invoked when an AST transformation is
 * activated. For Global AST Transformations, this interface is called once per SourceUnit, which is usually a
 * Groovy source file. For Local AST Transformations, this interface is invoked once every time the Local annotation
 * marker is encountered.
 * 
 * You must annotate this class with {@link GroovyASTTransformation} so that Groovy knows which
 * {@link org.codehaus.groovy.control.CompilePhase} to run in.
 *
 * @see GroovyASTTransformation
 * @author Danno Ferrin (shemnon)
 */
public interface ASTTransformation {

    /**
     * The method is invoked when an AST Transformation is active. For local transformations, it is invoked once
     * each time the local annotation is encountered. For global transformations, it is invoked once for every source
     * unit, which is typically a source file.
     *
     * @param nodes The ASTnodes when the call was triggered. Element 0 is the AnnotationNode that triggered this
     *      annotation to be activated. Element 1 is the AnnotatedNode decorated, such as a MethodNode or ClassNode. For
     *      global transformations it is usually safe to ignore this parameter.
     * @param source The source unit being compiled. The source unit may contain several classes. For global transformations,
     *      information about the AST can be retrieved from this object. 
     */
    void visit(ASTNode nodes[], SourceUnit source);
}