001package ball.annotation.processing;
002/*-
003 * ##########################################################################
004 * Utilities
005 * $Id: AntTaskProcessor.java 6112 2020-06-04 02:35:31Z ball $
006 * $HeadURL: svn+ssh://svn.hcf.dev/var/spool/scm/repository.svn/ball-util/trunk/src/main/java/ball/annotation/processing/AntTaskProcessor.java $
007 * %%
008 * Copyright (C) 2008 - 2020 Allen D. Ball
009 * %%
010 * Licensed under the Apache License, Version 2.0 (the "License");
011 * you may not use this file except in compliance with the License.
012 * You may obtain a copy of the License at
013 *
014 *      http://www.apache.org/licenses/LICENSE-2.0
015 *
016 * Unless required by applicable law or agreed to in writing, software
017 * distributed under the License is distributed on an "AS IS" BASIS,
018 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
019 * See the License for the specific language governing permissions and
020 * limitations under the License.
021 * ##########################################################################
022 */
023import ball.annotation.ServiceProviderFor;
024import ball.util.ant.taskdefs.AntTask;
025import javax.annotation.processing.Processor;
026import javax.annotation.processing.RoundEnvironment;
027import javax.lang.model.element.AnnotationMirror;
028import javax.lang.model.element.AnnotationValue;
029import javax.lang.model.element.Element;
030import javax.lang.model.element.TypeElement;
031import lombok.NoArgsConstructor;
032import lombok.ToString;
033
034import static javax.tools.Diagnostic.Kind.ERROR;
035import static org.apache.commons.lang3.StringUtils.isEmpty;
036
037/**
038 * {@link Processor} implementation to check {@link Class}es annotated with
039 * {@link AntTask}:
040 * <ol>
041 *   <li value="1">Are an instance of {@link org.apache.tools.ant.Task},</li>
042 *   <li value="2">Concrete, and</li>
043 *   <li value="3">Have a public no-argument constructor</li>
044 * </ol>
045 *
046 * @author {@link.uri mailto:ball@hcf.dev Allen D. Ball}
047 * @version $Revision: 6112 $
048 */
049@ServiceProviderFor({ Processor.class })
050@For({ AntTask.class })
051@NoArgsConstructor @ToString
052public class AntTaskProcessor extends AnnotatedProcessor {
053    @Override
054    protected void process(RoundEnvironment roundEnv,
055                           TypeElement annotation, Element element) {
056        super.process(roundEnv, annotation, element);
057
058        AnnotationMirror mirror = getAnnotationMirror(element, annotation);
059        AnnotationValue value = getAnnotationValue(mirror, "value");
060
061        if (isEmpty((String) value.getValue())) {
062            print(ERROR, element, mirror, value,
063                  "value() must be non-empty");
064        }
065    }
066}