#14 Model Inferrer & Scripting Language

grammar org.xtext.example.mydsl.MyDsl with org.eclipse.xtext.xbase.Xbase
generate myDsl "http://www.xtext.org/example/mydsl/MyDsl"

Model:
    greetings+=Greeting*;
        
Greeting:
    'Hello' name=ID '!';

package org.xtext.example.mydsl.jvmmodel

import com.google.inject.Inject
import org.eclipse.xtext.xbase.jvmmodel.AbstractModelInferrer
import org.eclipse.xtext.xbase.jvmmodel.IJvmDeclaredTypeAcceptor
import org.eclipse.xtext.xbase.jvmmodel.JvmTypesBuilder
import org.xtext.example.mydsl.myDsl.Model

class MyDslJvmModelInferrer extends AbstractModelInferrer {
  @Inject extension JvmTypesBuilder

  // Here you explain how your model is mapped to Java elements, by writing the actual translation code.
  def dispatch void infer(Model element, IJvmDeclaredTypeAcceptor acceptor, boolean isPreIndexingPhase) {
    acceptor.accept(element.toClass("my.company.greeting.MyGreetings"))
      .initializeLater([
        for (greeting : element.greetings) {
          members += greeting.toMethod("hello" + greeting.name, greeting.newTypeRef(typeof(String))) [
            body = [
              append('''return "Hello «greeting.name»";''')
            ]
          ]
        }
      ]
    )
  }
}

Hello World!
Hello Xtext!

package my.company.greeting;

public class MyGreetings {
  public String helloWorld() {
    return "Hello World";
  }
  
  public String helloXtext() {
    return "Hello Xtext";
  }
}

/*******************************************************************************
 * Copyright (c) 2012 itemis AG (http://www.itemis.eu) and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 ******************************************************************************/
grammar org.xtext.scripting.Scripting with org.eclipse.xtext.xbase.Xbase

generate scripting "http://www.xtext.org/scripting/Scripting"
import "http://www.eclipse.org/xtext/xbase/Xbase"

Script returns XBlockExpression:
        {Script}
        ((expressions+=XExpressionInsideBlock | imports+=Import) ';'?)*;

Import:
        'import' importedNamespace=QualifiedNameWithWildcard;
        
QualifiedNameWithWildcard:
        QualifiedName '.*'?;

/*******************************************************************************
 * Copyright (c) 2012 itemis AG (http://www.itemis.eu) and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 ******************************************************************************/
package org.xtext.scripting.jvmmodel

import com.google.inject.Inject
import org.eclipse.xtext.xbase.jvmmodel.AbstractModelInferrer
import org.eclipse.xtext.xbase.jvmmodel.IJvmDeclaredTypeAcceptor
import org.eclipse.xtext.xbase.jvmmodel.JvmTypesBuilder
import org.xtext.scripting.scripting.Script
import static org.xtext.scripting.jvmmodel.ScriptingJvmModelInferrer.*

/**
 * Infers a Java class with a main method from a {@link Script}.
 */
class ScriptingJvmModelInferrer extends AbstractModelInferrer {
  @Inject extension JvmTypesBuilder

  def dispatch void infer(Script script, IJvmDeclaredTypeAcceptor acceptor, boolean isPreIndexingPhase) {
    val className = script.eResource.URI.trimFileExtension.lastSegment
    acceptor.accept(script.toClass(className)).initializeLater [
      members += script.toMethod('main', script.newTypeRef(Void::TYPE)) [
        parameters += script.toParameter("args", script.newTypeRef(typeof(String)).addArrayTypeDimension)
        setStatic(true)
        body = script
      ]
    ]
  }
}

val a = 1
val b = 1
println(a + b)

import org.eclipse.xtext.xbase.lib.InputOutput;

public class Print {
  public static void main(final String[] args) {
    final int a = 1;
    final int b = 1;
    int _plus = (a + b);
    InputOutput.<Integer>println(Integer.valueOf(_plus));
  }
}