Annotation Processing Tools - Droidcon Madrid 2015

Transcript

1. Annotation Processing Tools 101
2. Txus Ballesteros @txusballesteros Rubén Serrano @akelael
3. Agenda 1. Annotation Processing Tool 2. Discusión 3. Caso práctico
4. ¿Qué es eso de APT?
5. public @interface DummyAnnotiation {} Anotación
6. Retención • Constructor • Atributo • Variable • Método • Parámetro • Etc. • Source • Class • Runtime Objetivo
7. Anotación @Retention(CLASS) @Target(FIELD)
 public @interface InjectView {
 int value();
 }
8. Runtime Class tiene la magia: • getAnnotation(Class<T> annotationType) • getAnnotations() • getDeclaredAnnotations() • isAnnotationPresent(Class<T> annotationType)
9. Mirror API http://docs.oracle.com/javase/1.5.0/docs/guide/apt/mirror/overview-summary.html
10. Discusión
11. Caso Práctico
12. Android Transformer https://github.com/txusballesteros/android-transformer
13. Creando Anotaciones @Retention(RetentionPolicy.SOURCE) @Target(ElementType.TYPE) public @interface Mappable {
 
 Class<?> with();
 }
14. Creando Anotaciones @Retention(RetentionPolicy.SOURCE) @Target(ElementType.TYPE) public @interface Mappable {
 
 Class<?> with();
 }
15. Configurando las Anotaciones @Retention(RetentionPolicy.SOURCE) @Target(ElementType.TYPE) public @interface Mappable {
 
 Class<?> with();
 }
16. Configurando las Anotaciones @Retention(RetentionPolicy.SOURCE) @Target(ElementType.TYPE) public @interface Mappable {
 
 Class<?> with();
 }
17. @SupportedSourceVersion(SourceVersion.RELEASE_7)
 @SupportedAnnotationTypes({
 "com.mobandme.android.transformer.compiler.Mapping",
 "com.mobandme.android.transformer.compiler.Mappable",
 "com.mobandme.android.transformer.compiler.Parse"
 })
 public class AnnotationsProcessor extends AbstractProcessor {
 
 RoundEnvironment roundEnvironment;
 Map<String, MapperInfo> mappersList;
 
 @Override
 public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment roundEnv) {
 return true;
 } Creando el Procesador
18. @SupportedSourceVersion(SourceVersion.RELEASE_7)
 @SupportedAnnotationTypes({
 "com.mobandme.android.transformer.compiler.Mapping",
 "com.mobandme.android.transformer.compiler.Mappable",
 "com.mobandme.android.transformer.compiler.Parse"
 })
 public class AnnotationsProcessor extends AbstractProcessor {
 
 RoundEnvironment roundEnvironment;
 Map<String, MapperInfo> mappersList;
 
 @Override
 public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment roundEnv) {
 return true;
 } Creando el Procesador
19. @SupportedSourceVersion(SourceVersion.RELEASE_7)
 @SupportedAnnotationTypes({
 "com.mobandme.android.transformer.compiler.Mapping",
 "com.mobandme.android.transformer.compiler.Mappable",
 "com.mobandme.android.transformer.compiler.Parse"
 })
 public class AnnotationsProcessor extends AbstractProcessor {
 
 RoundEnvironment roundEnvironment;
 Map<String, MapperInfo> mappersList;
 
 @Override
 public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment roundEnv) {
 return true;
 } Configurando el Procesador
20. Implementando el Procesador @SupportedSourceVersion(SourceVersion.RELEASE_7)
 @SupportedAnnotationTypes({
 "com.mobandme.android.transformer.compiler.Mapping",
 "com.mobandme.android.transformer.compiler.Mappable",
 "com.mobandme.android.transformer.compiler.Parse"
 })
 public class AnnotationsProcessor extends AbstractProcessor {
 
 RoundEnvironment roundEnvironment;
 Map<String, MapperInfo> mappersList;
 
 @Override
 public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment roundEnv) {
 return true;
 }
21. Implementando el Procesador private void processMappedAnnotationElements() {
 Set<? extends Element> elements = roundEnvironment.getElementsAnnotatedWith(Mapped.class); 
 for (Element mappedElement : elements) {
 if (mappedElement.getKind() == ElementKind.FIELD) {
 Mapped mappedAnnotation = mappedElement.getAnnotation(Mapped.class);
 String toFieldName = mappedAnnotation.toField();
 }
 }
 }
22. Implementando el Procesador private void processMappedAnnotationElements() {
 Set<? extends Element> elements = roundEnvironment.getElementsAnnotatedWith(Mapped.class); 
 for (Element mappedElement : elements) {
 if (mappedElement.getKind() == ElementKind.FIELD) {
 Mapped mappedAnnotation = mappedElement.getAnnotation(Mapped.class);
 String toFieldName = mappedAnnotation.toField();
 }
 }
 }
23. Implementando el Procesador private void processMappedAnnotationElements() {
 Set<? extends Element> elements = roundEnvironment.getElementsAnnotatedWith(Mapped.class); 
 for (Element mappedElement : elements) {
 if (mappedElement.getKind() == ElementKind.FIELD) {
 Mapped mappedAnnotation = mappedElement.getAnnotation(Mapped.class);
 String toFieldName = mappedAnnotation.toField();
 }
 }
 }
24. Implementando el Procesador private void processMappedAnnotationElements() {
 Set<? extends Element> elements = roundEnvironment.getElementsAnnotatedWith(Mapped.class); 
 for (Element mappedElement : elements) {
 if (mappedElement.getKind() == ElementKind.FIELD) {
 Mapped mappedAnnotation = mappedElement.getAnnotation(Mapped.class);
 String toFieldName = mappedAnnotation.toField();
 }
 }
 }
25. Generando el Código JavaFileObject file = processingEnv.getFiler().createSourceFile(name);
 BufferedWriter buffer = new BufferedWriter(file.openWriter());
 //… buffer.close();
26. Configurando el Entorno com.mobandme.android.transformer.compiler.internal.AnnotationsProcessor
27. Configuración de Gradle para el Compilador buildscript {
 repositories {
 maven {
 url "https://oss.sonatype.org/content/repositories/snapshots/"
 }
 jcenter()
 }
 dependencies {
 classpath 'com.jimdo.gradle:gradle-apt-plugin:0.5-SNAPSHOT'
 }
 }
 
 apply plugin: 'java'
 apply plugin: 'apt'
28. El resultado final
29. ¿Preguntas?