/*
* Copyright 2011 JBoss, by Red Hat, Inc
*
* 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.jboss.errai.databinding.rebind;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.net.URL;
import java.util.Collection;
import java.util.Enumeration;
import java.util.HashSet;
import java.util.PropertyResourceBundle;
import java.util.ResourceBundle;
import java.util.Set;
import org.jboss.errai.codegen.Cast;
import org.jboss.errai.codegen.InnerClass;
import org.jboss.errai.codegen.Parameter;
import org.jboss.errai.codegen.Statement;
import org.jboss.errai.codegen.Variable;
import org.jboss.errai.codegen.builder.ClassStructureBuilder;
import org.jboss.errai.codegen.builder.MethodBlockBuilder;
import org.jboss.errai.codegen.builder.impl.ClassBuilder;
import org.jboss.errai.codegen.builder.impl.ObjectBuilder;
import org.jboss.errai.codegen.meta.MetaClass;
import org.jboss.errai.codegen.meta.MetaClassFactory;
import org.jboss.errai.codegen.meta.MetaParameterizedType;
import org.jboss.errai.codegen.meta.MetaType;
import org.jboss.errai.codegen.util.Stmt;
import org.jboss.errai.common.metadata.RebindUtils;
import org.jboss.errai.config.rebind.EnvUtil;
import org.jboss.errai.config.util.ClassScanner;
import org.jboss.errai.databinding.client.BindableProxyFactory;
import org.jboss.errai.databinding.client.BindableProxyLoader;
import org.jboss.errai.databinding.client.BindableProxyProvider;
import org.jboss.errai.databinding.client.api.Bindable;
import org.jboss.errai.databinding.client.api.Convert;
import org.jboss.errai.databinding.client.api.Converter;
import org.jboss.errai.databinding.client.api.DefaultConverter;
import org.jboss.errai.databinding.client.api.InitialState;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.google.gwt.core.ext.Generator;
import com.google.gwt.core.ext.GeneratorContext;
import com.google.gwt.core.ext.TreeLogger;
import com.google.gwt.core.ext.UnableToCompleteException;
import com.google.gwt.core.ext.typeinfo.JClassType;
/**
* Generates the proxy loader for {@link Bindable}s.
*
* @author Christian Sadilek <csadilek@redhat.com>
*/
public class BindableProxyLoaderGenerator extends Generator {
private final Logger log = LoggerFactory.getLogger(BindableProxyLoaderGenerator.class);
@Override
public String generate(TreeLogger logger, GeneratorContext context, String typeName)
throws UnableToCompleteException {
String packageName = null;
String className = null;
try {
JClassType classType = context.getTypeOracle().getType(typeName);
packageName = classType.getPackage().getName();
className = classType.getSimpleSourceName() + "Impl";
PrintWriter printWriter = context.tryCreate(logger, packageName, className);
// If code has not already been generated.
if (printWriter != null) {
printWriter.append(generate(context, className));
context.commit(logger, printWriter);
}
}
catch (Throwable e) {
logger.log(TreeLogger.ERROR, "Error generating data-binding extensions", e);
}
return packageName + "." + className;
}
private String generate(final GeneratorContext context, final String className) {
final File fileCacheDir = RebindUtils.getErraiCacheDir();
final File cacheFile = new File(fileCacheDir.getAbsolutePath() + "/" + className + ".java");
log.info("generating bindable proxy loader class.");
final String gen = generate(context);
RebindUtils.writeStringToFile(cacheFile, gen);
return gen;
}
private String generate(final GeneratorContext context) {
ClassStructureBuilder<?> classBuilder = ClassBuilder.implement(BindableProxyLoader.class);
MethodBlockBuilder<?> loadProxies = classBuilder.publicMethod(void.class, "loadBindableProxies");
Collection<MetaClass> annotatedBindableTypes =
ClassScanner.getTypesAnnotatedWith(Bindable.class, RebindUtils.findTranslatablePackages(context));
Set<MetaClass> bindableTypes = new HashSet<MetaClass>(annotatedBindableTypes);
bindableTypes.addAll(getBindableTypesFromErraiAppProperties());
for (MetaClass bindable : bindableTypes) {
if (bindable.isFinal()) {
throw new RuntimeException("@Bindable type cannot be final: " + bindable.getFullyQualifiedName());
}
if (bindable.getDeclaredConstructor() == null || !bindable.getDeclaredConstructor().isPublic()) {
throw new RuntimeException("@Bindable type needs a public default no-arg constructor: "
+ bindable.getFullyQualifiedName());
}
ClassStructureBuilder<?> bindableProxy = new BindableProxyGenerator(bindable).generate();
loadProxies.append(new InnerClass(bindableProxy.getClassDefinition()));
Statement proxyProvider =
ObjectBuilder.newInstanceOf(BindableProxyProvider.class)
.extend()
.publicOverridesMethod("getBindableProxy", Parameter.of(bindable, "model"),
Parameter.of(InitialState.class, "state"))
.append(Stmt.nestedCall(Stmt.newObject(bindableProxy.getClassDefinition())
.withParameters(Cast.to(bindable, Stmt.loadVariable("model")), Variable.get("state"))).returnValue())
.finish()
.publicOverridesMethod("getBindableProxy", Parameter.of(InitialState.class, "state"))
.append(
Stmt.nestedCall(
Stmt.newObject(bindableProxy.getClassDefinition()).withParameters(Variable.get("state")))
.returnValue())
.finish()
.finish();
loadProxies.append(Stmt.invokeStatic(BindableProxyFactory.class, "addBindableProxy", bindable, proxyProvider));
}
generateDefaultConverterRegistrations(loadProxies, context);
classBuilder = (ClassStructureBuilder<?>) loadProxies.finish();
return classBuilder.toJavaString();
}
/**
* Reads all bindable types from all ErraiApp.properties files on the classpath.
*
* @return a set of meta classes representing the configured bindable types.
*/
private Set<MetaClass> getBindableTypesFromErraiAppProperties() {
final Set<MetaClass> bindableTypes = new HashSet<MetaClass>();
final Enumeration<URL> erraiAppProperties = EnvUtil.getErraiAppProperties();
while (erraiAppProperties.hasMoreElements()) {
InputStream inputStream = null;
try {
final URL url = erraiAppProperties.nextElement();
log.debug("Checking " + url.getFile() + " for bindable types...");
inputStream = url.openStream();
final ResourceBundle props = new PropertyResourceBundle(inputStream);
for (final String key : props.keySet()) {
if (key.equals("errai.ui.bindableTypes")) {
for (final String s : props.getString(key).split(" ")) {
try {
bindableTypes.add(MetaClassFactory.get(s.trim()));
}
catch (Exception e) {
throw new RuntimeException("Could not find class defined in ErraiApp.properties as bindable type: " + s);
}
}
break;
}
}
}
catch (IOException e) {
throw new RuntimeException("Error reading ErraiApp.properties", e);
}
finally {
if (inputStream != null) {
try {
inputStream.close();
}
catch (IOException e) {
log.warn("Failed to close input stream", e);
}
}
}
}
return bindableTypes;
}
private void generateDefaultConverterRegistrations(final MethodBlockBuilder<?> loadProxies,
final GeneratorContext context) {
for (MetaClass converter : ClassScanner.getTypesAnnotatedWith(DefaultConverter.class,
RebindUtils.findTranslatablePackages(context))) {
Statement registerConverterStatement = null;
for (MetaClass iface : converter.getInterfaces()) {
if (iface.getErased().equals(MetaClassFactory.get(Converter.class))) {
MetaParameterizedType parameterizedInterface = iface.getParameterizedType();
if (parameterizedInterface != null) {
MetaType[] typeArgs = parameterizedInterface.getTypeParameters();
if (typeArgs != null && typeArgs.length == 2) {
registerConverterStatement = Stmt.invokeStatic(Convert.class, "registerDefaultConverter",
typeArgs[0], typeArgs[1], Stmt.newObject(converter));
}
}
}
}
if (registerConverterStatement != null) {
loadProxies.append(registerConverterStatement);
}
else {
log.warn("Ignoring @DefaultConverter: " + converter
+ "! Make sure it implements Converter and specifies type arguments for the model and widget type");
}
}
}
}