/*
* Copyright 2013 NGDATA nv
*
* 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.lilyproject.tools.restresourcegenerator;
import javax.annotation.processing.AbstractProcessor;
import javax.annotation.processing.Filer;
import javax.annotation.processing.RoundEnvironment;
import javax.annotation.processing.SupportedAnnotationTypes;
import javax.lang.model.element.Element;
import javax.lang.model.element.TypeElement;
import javax.ws.rs.Path;
import java.io.PrintWriter;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
* An annotation processor to automatically generate alternatives of some JAX-RS resource
* classes. This will be done for classes annotated with annotations like {@link GenerateRepositoryAndTableResource}.
*/
@SupportedAnnotationTypes(
{"org.lilyproject.tools.restresourcegenerator.GenerateRepositoryAndTableResource",
"org.lilyproject.tools.restresourcegenerator.GenerateTableResource",
"org.lilyproject.tools.restresourcegenerator.GenerateRepositoryResource"})
public class GenerateRepositoryAndTableResourcesProcessor extends AbstractProcessor {
private static Map<String, ResourceClassGenerator> generators = new HashMap<String, ResourceClassGenerator>();
static {
generators.put(GenerateTableResource.class.getName(), new TableBasedResourceGenerator());
generators.put(GenerateRepositoryResource.class.getName(), new RepositoryBasedResourceGenerator());
generators.put(GenerateRepositoryAndTableResource.class.getName(), new RepositoryAndTableBasedResourceGenerator());
}
@Override
public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment roundEnv) {
for (TypeElement annotation : annotations) {
for (Element element : roundEnv.getElementsAnnotatedWith(annotation)) {
Path pathAnnotation = element.getAnnotation(Path.class);
if (pathAnnotation == null) {
throw new RuntimeException("A JAX-RS resource with the "
+ GenerateRepositoryAndTableResource.class.getSimpleName()
+ " annotation is missing a javax.ws.rs.Path annotation: " + element.toString());
}
String jaxRsPath = pathAnnotation.value();
Filer filer = processingEnv.getFiler();
String packageName = element.getEnclosingElement().toString();
String className = element.getSimpleName().toString();
generators.get(annotation.getQualifiedName().toString())
.generateResourceClass(packageName, className, jaxRsPath, filer);
}
}
return true;
}
private static interface ResourceClassGenerator {
void generateResourceClass(String packageName, String className, String jaxRsPath, Filer filer);
}
private static class TableBasedResourceGenerator implements ResourceClassGenerator {
@Override
public void generateResourceClass(String packageName, String className, String jaxRsPath, Filer filer) {
System.out.println("Generating /table/{tableName} variant of JAX-RS class " + packageName + "." + className);
try {
String generatedClassName = "TableBased" + className;
PrintWriter writer = new PrintWriter(filer.createSourceFile(packageName + "." + generatedClassName).openWriter());
writer.println("package " + packageName + ";");
writer.println();
writer.println("import javax.ws.rs.Path;");
writer.println();
writer.println("@TableEnabled");
writer.println("@Path(\"table/{tableName}/" + escapeJavaString(jaxRsPath) + "\")");
writer.println("public class " + generatedClassName + " extends " + className + " {");
writer.println("}");
writer.close();
} catch (Exception e) {
throw new RuntimeException(e);
}
}
}
private static class RepositoryBasedResourceGenerator implements ResourceClassGenerator {
@Override
public void generateResourceClass(String packageName, String className, String jaxRsPath, Filer filer) {
try {
// Note that the {repositoryName} wildcard conflicts with some other resources at the same level,
// such as schema. But its unlikely one will call his repository that way, and the alternatives seemed
// worse, except for starting with a new API under a different root.
System.out.println("Generating /{repositoryName} variant of JAX-RS class " + packageName + "." + className);
String generatedClassName = "RepositoryBased" + className;
PrintWriter writer = new PrintWriter(filer.createSourceFile(packageName + "." + generatedClassName).openWriter());
writer.println("package " + packageName + ";");
writer.println();
writer.println("import javax.ws.rs.Path;");
writer.println();
writer.println("@RepositoryEnabled");
writer.println("@Path(\"{repositoryName}/" + escapeJavaString(jaxRsPath) + "\")");
writer.println("public class " + generatedClassName + " extends " + className + " {");
writer.println("}");
writer.close();
} catch (Exception e) {
throw new RuntimeException(e);
}
}
}
private static class RepositoryAndTableBasedResourceGenerator implements ResourceClassGenerator {
@Override
public void generateResourceClass(String packageName, String className, String jaxRsPath, Filer filer) {
try {
System.out.println("Generating /{repositoryName}/table/{tableName} variant of JAX-RS class " + packageName + "." + className);
String generatedClassName = "RepositoryAndTableBased" + className;
PrintWriter writer = new PrintWriter(filer.createSourceFile(packageName + "." + generatedClassName).openWriter());
writer.println("package " + packageName + ";");
writer.println();
writer.println("import javax.ws.rs.Path;");
writer.println();
writer.println("@TableEnabled");
writer.println("@RepositoryEnabled");
writer.println("@Path(\"{repositoryName}/table/{tableName}/" + escapeJavaString(jaxRsPath) + "\")");
writer.println("public class " + generatedClassName + " extends " + className + " {");
writer.println("}");
writer.close();
} catch (Exception e) {
throw new RuntimeException(e);
}
}
}
private static String escapeJavaString(String input) {
return input.replaceAll(Pattern.quote("\\"), Matcher.quoteReplacement("\\\\"));
}
}