Java tutorial
package ch.unifr.pai.twice.comm.serverPush.rebind; /* * Copyright 2013 Oliver Schmid * 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. */ import java.io.PrintWriter; import ch.unifr.pai.twice.authentication.client.security.MessagingException; import ch.unifr.pai.twice.authentication.client.security.TWICESecurityManager; import ch.unifr.pai.twice.comm.serverPush.client.RemoteEvent; import ch.unifr.pai.twice.comm.serverPush.client.RemoteEventWrapper; import ch.unifr.pai.twice.comm.serverPush.client.UndoableRemoteEvent; import ch.unifr.pai.twice.comm.serverPush.client.UndoableRemoteEventWrapper; 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; import com.google.gwt.core.ext.typeinfo.JField; import com.google.gwt.core.ext.typeinfo.JMethod; import com.google.gwt.core.ext.typeinfo.NotFoundException; import com.google.gwt.event.shared.GwtEvent; import com.google.gwt.event.shared.GwtEvent.Type; import com.google.gwt.json.client.JSONValue; import com.google.gwt.user.rebind.ClassSourceFileComposerFactory; import com.google.gwt.user.rebind.SourceWriter; /** * Generator logic for remote event serialization. Generation takes place at compile time * * @author Oliver Schmid * */ public class RemoteEventSerializerGenerator extends Generator { @Override public String generate(TreeLogger logger, GeneratorContext context, String typeName) throws UnableToCompleteException { // Build a new class, that implements a "paintScreen" method JClassType classType; try { classType = context.getTypeOracle().getType(typeName); JClassType superClass = classType.getSuperclass(); JClassType[] generics = superClass.isParameterized().getTypeArgs(); JClassType eventHandlerClass = generics[0]; // Here you would retrieve the metadata based on typeName for this // Screen SourceWriter src = getSourceWriter(classType, context, logger); if (src != null) { src.println("@Override"); src.println("public " + String.class.getName() + " getEventType(){"); src.println("return " + classType.getQualifiedSourceName() + ".class.getName();"); src.println("}"); if (superClass.getQualifiedSourceName().equals(RemoteEventWrapper.class.getName()) || superClass.getQualifiedSourceName().equals(UndoableRemoteEventWrapper.class.getName())) { JClassType eventClass = generics[1]; src.println("@Override"); src.println("public void wrap(" + eventClass.getQualifiedSourceName() + " event){"); for (JMethod method : classType.getMethods()) { String realMethodName = method.getName().replaceAll("_", "()."); src.println("setProperty(\"" + method.getName() + "\", " + String.class.getName() + ".valueOf(event." + realMethodName + "()));"); } src.println("}"); for (JMethod method : classType.getMethods()) { if (method.isAbstract()) { src.println(); src.println("@Override"); src.println("public " + String.class.getName() + " " + method.getName() + "(){"); src.println( JSONValue.class.getName() + " value = json.get(\"" + method.getName() + "\");"); src.println( "return value!=null && value.isString()!=null ? value.isString().stringValue() : null;"); src.println("}"); } } src.println(); } src.println("@Override"); src.println("public " + GwtEvent.class.getName() + "." + Type.class.getSimpleName() + "<" + eventHandlerClass.getQualifiedSourceName() + "> getAssociatedType() {"); src.println("\treturn " + classType.getQualifiedSourceName() + ".TYPE;"); src.println("}"); src.println(); src.println("@Override"); src.println( "protected void dispatch(" + eventHandlerClass.getQualifiedSourceName() + " handler) {"); // for (JMethod m : eventHandlerClass.getMethods()) { // if(!m.getName().equals("undo")){ boolean undoable = classType .isAssignableTo(context.getTypeOracle().getType(UndoableRemoteEvent.class.getName())); if (undoable) { src.println("if(isUndo())"); src.println("handler.undo(this);"); src.println("else {"); src.println("handler.saveState(this);"); } src.println("\t handler.onEvent(this);"); if (undoable) { src.println("}"); } // } // } src.println("}"); src.println(); src.println("@Override"); src.println("public String serialize(" + TWICESecurityManager.class.getName() + " security) throws " + MessagingException.class.getName() + "{"); for (JField field : classType.getFields()) { if (!field.isStatic() && !field.isTransient()) { src.println("if(" + field.getName() + "!=null){"); src.println("setProperty(\"" + field.getName() + "\", String.valueOf(" + field.getName() + "));}"); } } src.println("return super.serialize(security);"); src.println("}"); src.println(); src.println("@Override"); src.println( "public " + RemoteEvent.class.getName() + "<" + eventHandlerClass.getQualifiedSourceName() + "> deserialize(String string, " + TWICESecurityManager.class.getName() + " security) throws " + MessagingException.class.getName() + "{"); src.println(RemoteEvent.class.getName() + " result = super.deserialize(string, security);"); for (JField field : classType.getFields()) { if (!field.isStatic()) { if (String.class.getName().equals(field.getType().getQualifiedSourceName())) src.println(field.getName() + " = getProperty(\"" + field.getName() + "\");"); else { src.println("String " + field.getName() + "Tmp = getProperty(\"" + field.getName() + "\");"); src.println(field.getName() + " = " + field.getName() + "Tmp!=null ? " + field.getType().getQualifiedSourceName() + ".valueOf(" + field.getName() + "Tmp) : null;"); } } } src.println("return result;"); src.println("}"); src.commit(logger); } return typeName + "Impl"; } catch (NotFoundException e) { e.printStackTrace(); } return null; } public SourceWriter getSourceWriter(JClassType classType, GeneratorContext context, TreeLogger logger) { String packageName = classType.getPackage().getName(); String simpleName = classType.getSimpleSourceName() + "Impl"; ClassSourceFileComposerFactory composer = new ClassSourceFileComposerFactory(packageName, simpleName); composer.setSuperclass(classType.getName()); composer.addImport(classType.getQualifiedSourceName()); // Need to add whatever imports your generated class needs. // composer.addImport("com.google.gwt.user.client.Window"); // composer.addImport("com.google.gwt.user.client.rpc.AsyncCallback"); // composer.addImport("com.google.gwt.user.client.ui.Button"); // composer.addImport("com.google.gwt.user.client.ui.RootPanel"); PrintWriter printWriter = context.tryCreate(logger, packageName, simpleName); if (printWriter == null) { return null; } else { SourceWriter sw = composer.createSourceWriter(context, printWriter); return sw; } } }