com.heisenberg.api.WorkflowEngineConfiguration.java Source code

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Here is the source code for com.heisenberg.api.WorkflowEngineConfiguration.java

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/*
 * Copyright 2014 Heisenberg Enterprises Ltd.
 * 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.heisenberg.api;

import javax.script.ScriptEngineManager;

import com.fasterxml.jackson.core.JsonFactory;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.heisenberg.api.activitytypes.Call;
import com.heisenberg.api.activitytypes.CallMapping;
import com.heisenberg.api.activitytypes.DefaultTask;
import com.heisenberg.api.activitytypes.EmbeddedSubprocess;
import com.heisenberg.api.activitytypes.EndEvent;
import com.heisenberg.api.activitytypes.ExclusiveGateway;
import com.heisenberg.api.activitytypes.HttpServiceTask;
import com.heisenberg.api.activitytypes.JavaServiceTask;
import com.heisenberg.api.activitytypes.ParallelGateway;
import com.heisenberg.api.activitytypes.ScriptTask;
import com.heisenberg.api.activitytypes.StartEvent;
import com.heisenberg.api.activitytypes.UserTask;
import com.heisenberg.impl.ExecutorServiceImpl;
import com.heisenberg.impl.SimpleProcessDefinitionCache;
import com.heisenberg.impl.SimpleServiceRegistry;
import com.heisenberg.impl.job.JobType;
import com.heisenberg.impl.json.JacksonJsonService;
import com.heisenberg.impl.memory.MemoryWorkflowEngine;
import com.heisenberg.impl.plugin.ActivityType;
import com.heisenberg.impl.plugin.Descriptors;
import com.heisenberg.impl.plugin.ServiceRegistry;
import com.heisenberg.impl.script.ScriptServiceImpl;
import com.heisenberg.impl.type.DataType;
import com.heisenberg.impl.type.ListType;
import com.heisenberg.impl.type.NumberType;
import com.heisenberg.impl.type.TextType;

/** Configurations to build a workflow engine.
 * 
 * By default, this configuration implementation produces a {@link MemoryWorkflowEngine}.
 * 
 * Subclasses of this configuration defined in other modules can produce other workflow engines.
 * E.g. MongoWorkflowEngineConfiguration or ClientWorkflowEngineConfiguration. 
 * 
 * <pre>{@code
 * WorkflowEngine workflowEngine = new WorkflowEngineConfiguration()
 *   .registerDataType(new MyCustomDataType())
 *   .registerJavaBeanType(MyCustomJavaBean.class)
 *   .registerActivityType(new MyCustomActivityType())
 *   .registerService(new MyCustomServiceObject())
 *   .buildWorkflowEngine();
 * }</pre>
 * 
 * 
 * @author Walter White
 */
public class WorkflowEngineConfiguration {

    protected String id;
    protected ServiceRegistry serviceRegistry;

    public WorkflowEngineConfiguration() {
        this(new SimpleServiceRegistry());
    }

    public WorkflowEngineConfiguration(ServiceRegistry serviceRegistry) {
        this.serviceRegistry = serviceRegistry;
        initializeDefaultInternalServices();
        initializeDefaultDataTypes();
        initializeDefaultActivityTypes();
    }

    protected void initializeDefaultInternalServices() {
        initializeObjectMapper();
        initializeJsonFactory();
        initializeScriptEngineManager();
        registerService(new Descriptors(serviceRegistry));
        registerService(new JacksonJsonService(serviceRegistry));
        registerService(new ScriptServiceImpl(serviceRegistry));
        registerService(new ExecutorServiceImpl(serviceRegistry));
        registerService(new SimpleProcessDefinitionCache(serviceRegistry));
    }

    protected void initializeScriptEngineManager() {
        registerService(new ScriptEngineManager());
    }

    protected void initializeJsonFactory() {
        registerService(new JsonFactory());
    }

    protected void initializeObjectMapper() {
        registerService(new ObjectMapper());
    }

    protected void initializeDefaultDataTypes() {
        this.registerDataType(new TextType());
        this.registerDataType(new NumberType());
        this.registerDataType(new ListType());
        this.registerJavaBeanType(CallMapping.class);
    }

    protected void initializeDefaultActivityTypes() {
        this.registerActivityType(new StartEvent());
        this.registerActivityType(new EndEvent());
        this.registerActivityType(new EmbeddedSubprocess());
        this.registerActivityType(new ExclusiveGateway());
        this.registerActivityType(new ParallelGateway());
        this.registerActivityType(new Call());
        this.registerActivityType(new ScriptTask());
        this.registerActivityType(new UserTask());
        this.registerActivityType(new DefaultTask());
        this.registerActivityType(new JavaServiceTask());
        this.registerActivityType(new HttpServiceTask());
    }

    public WorkflowEngine buildWorkflowEngine() {
        return new MemoryWorkflowEngine(this);
    }

    public WorkflowEngineConfiguration registerService(Object service) {
        serviceRegistry.registerService(service);
        return this;
    }

    public WorkflowEngineConfiguration registerJavaBeanType(Class<?> javaBeanType) {
        getDescriptors().registerJavaBeanType(javaBeanType);
        return this;
    }

    public WorkflowEngineConfiguration registerActivityType(ActivityType activityType) {
        getDescriptors().registerActivityType(activityType);
        return this;
    }

    public WorkflowEngineConfiguration registerDataType(DataType dataType) {
        getDescriptors().registerDataType(dataType);
        return this;
    }

    public WorkflowEngineConfiguration registerJobType(Class<? extends JobType> jobTypeClass) {
        getDescriptors().registerJobType(jobTypeClass);
        return this;
    }

    protected Descriptors getDescriptors() {
        return serviceRegistry.getService(Descriptors.class);
    }

    public WorkflowEngineConfiguration id(String id) {
        this.id = id;
        return this;
    }

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public ServiceRegistry getServiceRegistry() {
        return serviceRegistry;
    }

    public void setServiceRegistry(ServiceRegistry serviceRegistry) {
        this.serviceRegistry = serviceRegistry;
    }
}