NestedProcessorStringGenerator.java

/**
 * Mule Development Kit
 * Copyright 2010-2011 (c) MuleSoft, Inc.  All rights reserved.  http://www.mulesoft.com
 *
 * 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.mule.devkit.generation.mule;

import org.mule.api.NestedProcessor;
import org.mule.devkit.generation.AbstractModuleGenerator;
import org.mule.devkit.generation.DevKitTypeElement;
import org.mule.devkit.generation.GenerationException;
import org.mule.devkit.generation.NamingContants;
import org.mule.devkit.model.code.DefinedClass;
import org.mule.devkit.model.code.ExpressionFactory;
import org.mule.devkit.model.code.FieldVariable;
import org.mule.devkit.model.code.Method;
import org.mule.devkit.model.code.Modifier;
import org.mule.devkit.model.code.Variable;

import javax.lang.model.element.TypeElement;
import java.util.Map;

public class NestedProcessorStringGenerator extends AbstractModuleGenerator {

    public static final String ROLE = "NestedProcessorString";

    @Override
    protected boolean shouldGenerate(DevKitTypeElement typeElement) {
        return typeElement.hasProcessorMethodWithParameter(NestedProcessor.class) ||
               typeElement.hasProcessorMethodWithParameterListOf(NestedProcessor.class);
    }

    @Override
    protected void doGenerate(DevKitTypeElement typeElement) throws GenerationException {
        DefinedClass callbackClass = getNestedProcessorStringClass(typeElement);
        callbackClass._implements(ref(NestedProcessor.class));

        FieldVariable output = callbackClass.field(Modifier.PRIVATE, ref(String.class), "output");
        output.javadoc().add("Output string to be returned on process");

        generateSetter(callbackClass, output);

        generateCallbackConstructor(callbackClass, output);

        generateCallbackProcess(callbackClass, output);

        generateCallbackProcessWithPayload(callbackClass, output);

        generateCallbackProcessWithProperties(callbackClass, output);

        generateCallbackProcessWithPayloadAndProperties(callbackClass, output);

        context.setClassRole(ROLE, callbackClass);
    }

    private void generateCallbackProcessWithPayload(DefinedClass callbackClass, FieldVariable output) {
        Method process = callbackClass.method(Modifier.PUBLIC, ref(Object.class), "process");
        process._throws(ref(Exception.class));
        process.param(ref(Object.class), "payload");
        process.body()._return(output);
    }

    private void generateCallbackProcessWithPayloadAndProperties(DefinedClass callbackClass, FieldVariable output) {
        Method process = callbackClass.method(Modifier.PUBLIC, ref(Object.class), "process");
        process._throws(ref(Exception.class));
        process.param(ref(Object.class), "payload");
        process.param(ref(Map.class).narrow(ref(String.class)).narrow(ref(Object.class)), "properties");
        process.body()._return(output);
    }

    private void generateCallbackProcessWithProperties(DefinedClass callbackClass, FieldVariable output) {
        Method process = callbackClass.method(Modifier.PUBLIC, ref(Object.class), "processWithExtraProperties");
        process._throws(ref(Exception.class));
        process.param(ref(Map.class).narrow(ref(String.class)).narrow(ref(Object.class)), "properties");
        process.body()._return(output);
    }

    private void generateCallbackProcess(DefinedClass callbackClass, FieldVariable output) {
        Method process = callbackClass.method(Modifier.PUBLIC, ref(Object.class), "process");
        process._throws(ref(Exception.class));

        process.body()._return(output);
    }

    private void generateCallbackConstructor(DefinedClass callbackClass, FieldVariable output) {
        Method constructor = callbackClass.constructor(Modifier.PUBLIC);
        Variable output2 = constructor.param(ref(String.class), "output");
        constructor.body().assign(ExpressionFactory._this().ref(output), output2);
    }

    private DefinedClass getNestedProcessorStringClass(TypeElement type) {
        String processorCallbackClassName = context.getNameUtils().generateClassNameInPackage(type, NamingContants.CONFIG_NAMESPACE, NamingContants.NESTED_PROCESSOR_STRING_CLASS_NAME);
        org.mule.devkit.model.code.Package pkg = context.getCodeModel()._package(context.getNameUtils().getPackageName(processorCallbackClassName));
        DefinedClass clazz = pkg._class(context.getNameUtils().getClassName(processorCallbackClassName));

        context.setClassRole(ROLE, clazz);

        return clazz;
    }
}