/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.apache.streams.plugins;
import org.reflections.ReflectionUtils;
import org.reflections.Reflections;
import org.reflections.scanners.SubTypesScanner;
import org.reflections.scanners.TypeAnnotationsScanner;
import org.reflections.util.ConfigurationBuilder;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.File;
import java.io.Serializable;
import java.lang.reflect.Field;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.nio.file.StandardOpenOption;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.TreeMap;
import java.util.stream.Collectors;
import java.util.stream.Stream;
/**
* Embed within your own java code
*
* <p/>
* StreamsScalaGenerationConfig config = new StreamsScalaGenerationConfig();
* config.setTargetDirectory("target/generated-sources/scala");
* config.setTargetPackage("com.example");
* StreamsScalaSourceGenerator generator = new StreamsScalaSourceGenerator(config);
* generator.run();
*
*/
public class StreamsScalaSourceGenerator implements Runnable {
private static final Logger LOGGER = LoggerFactory.getLogger(StreamsScalaSourceGenerator.class);
private static final String LS = System.getProperty("line.separator");
private StreamsScalaGenerationConfig config;
private Reflections reflections;
private String outDir;
/**
* Run from CLI without Maven
*
* <p/>
* java -jar streams-plugin-scala-jar-with-dependencies.jar StreamsScalaSourceGenerator target/generated-sources
*
* @param args [targetDirectory, targetPackage]
* */
public static void main(String[] args) {
StreamsScalaGenerationConfig config = new StreamsScalaGenerationConfig();
List<String> sourcePackages = new ArrayList<>();
String targetDirectory = "target/generated-sources/pojo";
String targetPackage = "";
if ( args.length > 0 ) {
sourcePackages = Stream.of(args[0].split(",")).collect(Collectors.toList());
}
if ( args.length > 1 ) {
targetDirectory = args[1];
}
if ( args.length > 2 ) {
targetPackage = args[2];
}
config.setSourcePackages(sourcePackages);
config.setTargetPackage(targetPackage);
config.setTargetDirectory(targetDirectory);
StreamsScalaSourceGenerator streamsScalaSourceGenerator = new StreamsScalaSourceGenerator(config);
streamsScalaSourceGenerator.run();
}
/**
* StreamsScalaSourceGenerator constructor.
* @param config StreamsScalaGenerationConfig
*/
public StreamsScalaSourceGenerator(StreamsScalaGenerationConfig config) {
this.config = config;
this.outDir = config.getTargetDirectory().getAbsolutePath();
reflections = new Reflections(
new ConfigurationBuilder()
// TODO
.forPackages(
config.getSourcePackages()
.toArray(new String[config.getSourcePackages().size()])
)
.setScanners(
new SubTypesScanner(),
new TypeAnnotationsScanner()));
}
@Override
public void run() {
List<Class<?>> serializableClasses = detectSerializableClasses();
LOGGER.info("Detected {} serialiables:", serializableClasses.size());
for ( Class clazz : serializableClasses ) {
LOGGER.debug(clazz.toString());
}
List<Class<?>> pojoClasses = detectPojoClasses(serializableClasses);
LOGGER.info("Detected {} pojos:", pojoClasses.size());
for ( Class clazz : pojoClasses ) {
LOGGER.debug(clazz.toString());
}
List<Class<?>> traits = detectTraits(pojoClasses);
LOGGER.info("Detected {} traits:", traits.size());
for ( Class clazz : traits ) {
LOGGER.debug(clazz.toString());
}
List<Class<?>> cases = detectCases(pojoClasses);
LOGGER.info("Detected {} cases:", cases.size());
for ( Class clazz : cases ) {
LOGGER.debug(clazz.toString());
}
for ( Class clazz : traits ) {
String pojoPath = clazz.getPackage().getName().replace(".pojo.json", ".scala").replace(".","/") + "/traits/";
String pojoName = clazz.getSimpleName() + ".scala";
String pojoScala = renderTrait(clazz);
writeFile(outDir + "/" + pojoPath + pojoName, pojoScala);
}
for ( Class clazz : traits ) {
String pojoPath = clazz.getPackage().getName().replace(".pojo.json", ".scala").replace(".","/") + "/";
String pojoName = clazz.getSimpleName() + ".scala";
String pojoScala = renderClass(clazz);
writeFile(outDir + "/" + pojoPath + pojoName, pojoScala);
}
for ( Class clazz : cases ) {
String pojoPath = clazz.getPackage().getName().replace(".pojo.json", ".scala").replace(".","/") + "/";
String pojoName = clazz.getSimpleName() + ".scala";
String pojoScala = renderCase(clazz);
writeFile(outDir + "/" + pojoPath + pojoName, pojoScala);
}
}
private void writeFile(String pojoFile, String pojoScala) {
try {
File path = new File(pojoFile);
File dir = path.getParentFile();
if ( !dir.exists() ) {
dir.mkdirs();
}
Files.write(Paths.get(pojoFile), pojoScala.getBytes(), StandardOpenOption.CREATE_NEW);
} catch (Exception ex) {
LOGGER.error("Write Exception: {}", ex);
}
}
/**
* detectSerializableClasses.
* @return List of Serializable Classes
*/
public List<Class<?>> detectSerializableClasses() {
Set<Class<? extends Serializable>> classes =
reflections.getSubTypesOf(java.io.Serializable.class);
List<Class<?>> result = new ArrayList<>();
for ( Class clazz : classes ) {
result.add(clazz);
}
return result;
}
/**
* detect which Classes are Pojo Classes.
* @param classes List of candidate Pojo Classes
* @return List of actual Pojo Classes
*/
public List<Class<?>> detectPojoClasses(List<Class<?>> classes) {
List<Class<?>> result = new ArrayList<>();
for ( Class clazz : classes ) {
try {
clazz.newInstance().toString();
} catch ( Exception ex) {
//
}
// super-halfass way to know if this is a jsonschema2pojo
if ( clazz.getAnnotations().length >= 1 ) {
result.add(clazz);
}
}
return result;
}
private List<Class<?>> detectTraits(List<Class<?>> classes) {
List<Class<?>> traits = new ArrayList<>();
for ( Class clazz : classes ) {
if (reflections.getSubTypesOf(clazz).size() > 0) {
traits.add(clazz);
}
}
return traits;
}
private List<Class<?>> detectCases(List<Class<?>> classes) {
List<Class<?>> cases = new ArrayList<>();
for ( Class clazz : classes ) {
if (reflections.getSubTypesOf(clazz).size() == 0) {
cases.add(clazz);
}
}
return cases;
}
private String renderTrait(Class<?> pojoClass) {
StringBuffer stringBuffer = new StringBuffer();
stringBuffer.append("package ");
stringBuffer.append(pojoClass.getPackage().getName().replace(".pojo.json", ".scala"));
stringBuffer.append(".traits");
stringBuffer.append(LS);
stringBuffer.append("trait ").append(pojoClass.getSimpleName());
stringBuffer.append(" extends Serializable");
stringBuffer.append(" {");
Set<Field> fields = ReflectionUtils.getAllFields(pojoClass);
appendFields(stringBuffer, fields, "def", ";");
stringBuffer.append("}");
return stringBuffer.toString();
}
private String renderClass(Class<?> pojoClass) {
StringBuffer stringBuffer = new StringBuffer();
stringBuffer.append("package ");
stringBuffer.append(pojoClass.getPackage().getName().replace(".pojo.json", ".scala"));
stringBuffer.append(LS);
stringBuffer.append("import org.apache.commons.lang.builder.{HashCodeBuilder, EqualsBuilder, ToStringBuilder}");
stringBuffer.append(LS);
stringBuffer.append("class ").append(pojoClass.getSimpleName());
stringBuffer.append(" (");
Set<Field> fields = ReflectionUtils.getAllFields(pojoClass);
appendFields(stringBuffer, fields, "var", ",");
stringBuffer.append(")");
stringBuffer.append(" extends ").append(pojoClass.getPackage().getName().replace(".pojo.json", ".scala")).append(".traits.").append(pojoClass.getSimpleName());
stringBuffer.append(" with Serializable ");
stringBuffer.append("{ ");
stringBuffer.append(LS);
stringBuffer.append("override def equals(obj: Any) = obj match { ");
stringBuffer.append(LS);
stringBuffer.append(" case other: ");
stringBuffer.append(pojoClass.getSimpleName());
stringBuffer.append(" => other.getClass == getClass && EqualsBuilder.reflectionEquals(this,obj)");
stringBuffer.append(LS);
stringBuffer.append(" case _ => false");
stringBuffer.append(LS);
stringBuffer.append("}");
stringBuffer.append(LS);
stringBuffer.append("override def hashCode = new HashCodeBuilder().hashCode");
stringBuffer.append(LS);
stringBuffer.append("}");
return stringBuffer.toString();
}
private String renderCase(Class<?> pojoClass) {
StringBuffer stringBuffer = new StringBuffer();
stringBuffer.append("package ");
stringBuffer.append(pojoClass.getPackage().getName().replace(".pojo.json", ".scala"));
stringBuffer.append(LS);
stringBuffer.append("case class " + pojoClass.getSimpleName());
stringBuffer.append("(");
Set<Field> fields = ReflectionUtils.getAllFields(pojoClass);
appendFields(stringBuffer, fields, "var", ",");
stringBuffer.append(")");
if ( pojoClass.getSuperclass() != null && !pojoClass.getSuperclass().equals(java.lang.Object.class)) {
stringBuffer.append(" extends " + pojoClass.getSuperclass().getPackage().getName().replace(".pojo.json", ".scala") + ".traits." + pojoClass.getSuperclass().getSimpleName());
}
stringBuffer.append(LS);
return stringBuffer.toString();
}
private void appendFields(StringBuffer stringBuffer, Set<Field> fields, String varDef, String fieldDelimiter) {
if ( fields.size() > 0 ) {
stringBuffer.append(LS);
Map<String,Field> fieldsToAppend = uniqueFields(fields);
for ( Iterator<Field> iter = fieldsToAppend.values().iterator(); iter.hasNext(); ) {
Field field = iter.next();
if ( override( field ) ) {
stringBuffer.append("override ");
}
stringBuffer.append(varDef);
stringBuffer.append(" ");
stringBuffer.append(name(field));
stringBuffer.append(": ");
if ( option(field) ) {
stringBuffer.append("scala.Option[");
stringBuffer.append(type(field));
stringBuffer.append("]");
} else {
stringBuffer.append(type(field));
}
if ( !fieldDelimiter.equals(";") && value(field) != null) {
stringBuffer.append(" = ");
if ( option(field) ) {
stringBuffer.append("scala.Some(");
stringBuffer.append(value(field));
stringBuffer.append(")");
} else {
stringBuffer.append(value(field));
}
}
if ( iter.hasNext()) {
stringBuffer.append(fieldDelimiter);
}
stringBuffer.append(LS);
}
} else {
stringBuffer.append(LS);
}
}
private boolean option(Field field) {
return !field.getName().equals("verb") &&
!field.getType().equals(Map.class) &&
!field.getType().equals(List.class);
}
private String value(Field field) {
switch (field.getName()) {
case "verb":
return "\"post\"";
case "objectType":
return "\"application\"";
default:
return null;
}
}
private String type(Field field) {
if ( field.getType().equals(java.lang.String.class)) {
return "String";
} else if ( field.getType().equals(java.util.Map.class)) {
return "scala.collection.mutable.Map[String,Any]";
} else if ( field.getType().equals(java.util.List.class)) {
return "scala.collection.mutable.MutableList[Any]";
}
return field.getType().getCanonicalName().replace(".pojo.json", ".scala");
}
private Map<String,Field> uniqueFields(Set<Field> fieldset) {
Map<String,Field> fields = new TreeMap<>();
Field item = null;
for ( Iterator<Field> it = fieldset.iterator(); it.hasNext(); item = it.next() ) {
if ( item != null && item.getName() != null ) {
Field added = fields.put(item.getName(), item);
}
// ensure right class will get used
}
return fields;
}
private String name(Field field) {
if ( field.getName().equals("object")) {
return "obj";
} else {
return field.getName();
}
}
private boolean override(Field field) {
try {
return field.getDeclaringClass().getSuperclass().getField(field.getName()) != null;
} catch ( Exception ex ) {
return false;
}
}
}