/*
* Copyright 2014 Daniel Kurka
*
* 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 com.googlecode.mgwt.ui.generator;
import com.google.gwt.core.ext.BadPropertyValueException;
import com.google.gwt.core.ext.Generator;
import com.google.gwt.core.ext.GeneratorContext;
import com.google.gwt.core.ext.PropertyOracle;
import com.google.gwt.core.ext.SelectionProperty;
import com.google.gwt.core.ext.TreeLogger;
import com.google.gwt.core.ext.UnableToCompleteException;
import com.google.gwt.core.ext.typeinfo.JClassType;
import com.google.gwt.core.ext.typeinfo.NotFoundException;
import com.google.gwt.user.rebind.ClassSourceFileComposerFactory;
import com.google.gwt.user.rebind.SourceWriter;
import java.io.PrintWriter;
/**
* <h1>Considered internal</h1>
*
* @author Daniel Kurka
*/
public abstract class RebindingGenerator extends Generator {
protected static class WriteHolder {
String packageName;
String simpleName;
String fullName;
ClassSourceFileComposerFactory composer;
PrintWriter printWriter;
public WriteHolder(String packageName, String simpleName, ClassSourceFileComposerFactory composer, PrintWriter printWriter) {
this.packageName = packageName;
this.simpleName = simpleName;
this.composer = composer;
this.printWriter = printWriter;
this.fullName = packageName + "." + simpleName;
}
}
@Override
public String generate(TreeLogger logger, GeneratorContext context, String typeName) throws UnableToCompleteException {
SelectionProperty property = getSelectionProperty(logger, context, getSelectionPropertyName());
JClassType classType = getClassType(logger, context, typeName);
WriteHolder writeHolder = createWriteHolder(logger, context, classType, property, typeName);
if (writeHolder.printWriter == null) {
return writeHolder.fullName;
}
// start writing the implementation
SourceWriter writer = writeHolder.composer.createSourceWriter(context, writeHolder.printWriter);
writeImplementatioon(logger, property, writer);
return writeHolder.fullName;
}
protected abstract String getSelectionPropertyName();
protected abstract void writeImplementatioon(TreeLogger logger, SelectionProperty property, SourceWriter writer);
private JClassType getClassType(TreeLogger logger, GeneratorContext context, String typeName)
throws UnableToCompleteException {
try {
// get the type we are looking for
return context.getTypeOracle().getType(typeName);
} catch (NotFoundException e) {
// if we can`t get it die
logger.log(TreeLogger.ERROR, "can not find type: '" + typeName + "'", e);
throw new UnableToCompleteException();
}
}
private WriteHolder createWriteHolder(TreeLogger logger, GeneratorContext context, JClassType classType,
SelectionProperty property, String typeName) {
// get the package name
String packageName = classType.getPackage().getName();
// build name for implementation class
String simpleName = classType.getSimpleSourceName() + "_" + property.getCurrentValue();
PrintWriter printWriter = context.tryCreate(logger, packageName, simpleName);
ClassSourceFileComposerFactory composer = new ClassSourceFileComposerFactory(packageName, simpleName);
composer.addImplementedInterface(typeName);
return new WriteHolder(packageName, simpleName, composer, printWriter);
}
private SelectionProperty getSelectionProperty(TreeLogger logger, GeneratorContext context, String propertyName)
throws UnableToCompleteException {
// get the property oracle
PropertyOracle propertyOracle = context.getPropertyOracle();
SelectionProperty property = null;
try {
// get mgwt.os variable
property = propertyOracle.getSelectionProperty(logger, propertyName);
} catch (BadPropertyValueException e) {
// if we can`t find it die
logger.log(TreeLogger.ERROR, "can not resolve " + propertyName + " variable", e);
throw new UnableToCompleteException();
}
return property;
}
}