/*
* Copyright 2014 Alexey Andreev.
*
* 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.teavm.classlib.impl;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URL;
import java.util.*;
import org.teavm.codegen.SourceWriter;
import org.teavm.dependency.*;
import org.teavm.javascript.ni.Generator;
import org.teavm.javascript.ni.GeneratorContext;
import org.teavm.model.MethodDescriptor;
import org.teavm.model.MethodReference;
import org.teavm.model.ValueType;
/**
*
* @author Alexey Andreev <konsoletyper@gmail.com>
*/
public class ServiceLoaderSupport implements Generator, DependencyListener {
private Map<String, List<String>> serviceMap = new HashMap<>();
private DependencyNode allClassesNode;
private ClassLoader classLoader;
private DependencyStack stack;
public ServiceLoaderSupport(ClassLoader classLoader) {
this.classLoader = classLoader;
}
@Override
public void generate(GeneratorContext context, SourceWriter writer, MethodReference methodRef) throws IOException {
writer.append("if (!").appendClass("java.util.ServiceLoader").append(".$$services$$) {").indent()
.softNewLine();
writer.appendClass("java.util.ServiceLoader").append(".$$services$$ = true;").softNewLine();
for (Map.Entry<String, List<String>> entry : serviceMap.entrySet()) {
writer.appendClass(entry.getKey()).append(".$$serviceList$$ = [");
List<String> implementations = entry.getValue();
for (int i = 0; i < implementations.size(); ++i) {
if (i > 0) {
writer.append(", ");
}
String implName = implementations.get(i);
writer.append("[").appendClass(implName).append(", ").appendMethodBody(
new MethodReference(implName, new MethodDescriptor("<init>", ValueType.VOID)))
.append("]");
}
writer.append("];").softNewLine();
}
writer.outdent().append("}").softNewLine();
String param = context.getParameterName(1);
writer.append("var cls = " + param + ".$data;").softNewLine();
writer.append("if (!cls.$$serviceList$$) {").indent().softNewLine();
writer.append("return $rt_createArray($rt_objcls(), 0);").softNewLine();
writer.outdent().append("}").softNewLine();
writer.append("var result = $rt_createArray($rt_objcls(), cls.$$serviceList$$.length);").softNewLine();
writer.append("for (var i = 0; i < result.data.length; ++i) {").indent().softNewLine();
writer.append("var serviceDesc = cls.$$serviceList$$[i];").softNewLine();
writer.append("result.data[i] = new serviceDesc[0]();").softNewLine();
writer.append("serviceDesc[1](result.data[i]);").softNewLine();
writer.outdent().append("}").softNewLine();
writer.append("return result;").softNewLine();
}
@Override
public void started(DependencyAgent agent) {
allClassesNode = agent.createNode();
}
@Override
public void classAchieved(DependencyAgent agent, String className) {
try {
Enumeration<URL> resources = classLoader.getResources("META-INF/services/" + className);
while (resources.hasMoreElements()) {
URL resource = resources.nextElement();
try (InputStream stream = resource.openStream()) {
parseServiceFile(agent, className, stream);
}
}
} catch (IOException e) {
throw new RuntimeException(e);
}
}
private void parseServiceFile(DependencyAgent agent, String service, InputStream input) throws IOException {
BufferedReader reader = new BufferedReader(new InputStreamReader(input, "UTF-8"));
while (true) {
String line = reader.readLine();
if (line == null) {
break;
}
line = line.trim();
if (line.startsWith("#") || line.isEmpty()) {
continue;
}
List<String> implementors = serviceMap.get(service);
if (implementors == null) {
implementors = new ArrayList<>();
serviceMap.put(service, implementors);
}
implementors.add(line);
allClassesNode.propagate(agent.getType(line));
}
}
@Override
public void methodAchieved(final DependencyAgent agent, MethodDependency method) {
MethodReference ref = method.getReference();
if (ref.getClassName().equals("java.util.ServiceLoader") && ref.getName().equals("loadServices")) {
method.getResult().propagate(agent.getType("[java.lang.Object"));
stack = method.getStack();
allClassesNode.connect(method.getResult().getArrayItem());
method.getResult().getArrayItem().addConsumer(new DependencyConsumer() {
@Override public void consume(DependencyAgentType type) {
initConstructor(agent, type.getName());
}
});
}
}
private void initConstructor(DependencyAgent agent, String type) {
MethodReference ctor = new MethodReference(type, new MethodDescriptor("<init>", ValueType.VOID));
agent.linkMethod(ctor, stack).use();
}
@Override
public void fieldAchieved(DependencyAgent agent, FieldDependency field) {
}
}