jbpm 与 工作流模式 基本控制模式(一)

     工作流模式

     本文以jdpl/jar/src/test/java   jbpm3 关于workflow patterns 说明 jbpm 对 workflow patterns 的实现示例.

    基本控制模式 (Basic Control Flow Patterns)

    顺序 (sequence)
    Description :     An activity in a workow process is enabled after the completion of another
                            activity in the same process.
    描述:            :    同一个流程中, 一个活动在其他活动完成以后才能发生. 

   同义词        :       Sequential routing, serial routing.
    
   

java 代码

/*
 * JBoss, Home of Professional Open Source
 * Copyright 2005, JBoss Inc., and individual contributors as indicated
 * by the @authors tag. See the copyright.txt in the distribution for a
 * full listing of individual contributors.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */
package org.jbpm.jpdl.patterns;

import junit.framework.TestCase;

import org.jbpm.graph.def.ProcessDefinition;
import org.jbpm.graph.exe.ProcessInstance;
import org.jbpm.graph.exe.Token;

/**
 * http://is.tm.tue.nl/research/patterns/download/swf/pat_1.swf
 */
public class Wfp01SequenceTest extends TestCase {

  public void testSequence() {
    // create a simple definition with 3 states in sequence
    ProcessDefinition pd = ProcessDefinition.parseXmlString(
      "
    <process-definition>"</process-definition>
     +
      "   +
      "     +
      "  " +
      "   +
      "     +
      "  " +
      "   +
      "     +
      "  " +
      "   +
      "     +
      "  " +
      "   +
      ""
    );

    ProcessInstance pi = new ProcessInstance( pd );
    pi.signal();
    Token token = pi.getRootToken();
    assertSame( pd.getNode("a"), token.getNode() );

    token.signal();
    assertSame( pd.getNode("b"), token.getNode() );

    token.signal();
    assertSame( pd.getNode("c"), token.getNode() );

    token.signal();
    assertSame( pd.getNode("end"), token.getNode() );
  }
}

 
        <process-definition><start-state name="start"><state name="a"><state name="b"><state name="c">流程定义文件如下

     </state></state></state></start-state></process-definition>

xml 代码

<process-definition>
    <start-state name='start'>
        <transition to='a' />
    <!---->start-state>
    <state name='a'>
        <transition to='b' />
    <!---->state>
    <state name='b'>
        <transition to='c' />
    <!---->state>
    <state name='c'>
        <transition to='end' />
    <!---->state>
    <end-state name='end' />
<!---->process-definition>

   节点流程      start --> a --> b --> c --> end
    <process-definition><start-state name="start"><state name="a"><state name="b"><state name="c">
        本例中包括start , a , b ,c ,end 四个node.  token.signal() 可以理解为流程中当前节点(token对应节点) 活动结束. 代码一目了然. 不需要过多解释.
   
    


  并行分支（Parallet Split） 


Description :    A point in the workow process where a single thread of control splits into multiple threads of control which can be executed in parallel, thus allowing activities to be executed simultaneously or in any order.

描述            :     在分支点上,一个工作流程执行线程 分出多个执行线程同时并行执行, 多个分支线程可以同时以任意顺序执行.

同义词:            AND-split, parallel routing, fork.

</state></state></state></start-state></process-definition>

java 代码

/*
 * JBoss, Home of Professional Open Source
 * Copyright 2005, JBoss Inc., and individual contributors as indicated
 * by the @authors tag. See the copyright.txt in the distribution for a
 * full listing of individual contributors.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */
package org.jbpm.jpdl.patterns;

import junit.framework.TestCase;

import org.jbpm.graph.def.ProcessDefinition;
import org.jbpm.graph.exe.ProcessInstance;
import org.jbpm.graph.exe.Token;

/**
 * http://is.tm.tue.nl/research/patterns/download/swf/pat_2.swf
 */
public class Wfp02ParallelSplitTest extends TestCase {

  public void testParallelSplit() {
    ProcessDefinition pd = ProcessDefinition.parseXmlString(
      "
    <process-definition>"</process-definition>
     +
      "   +
      "     +
      "  " +
      "   +
      "     +
      "     +
      "  " +
      "   +
      "   +
      ""
    );

    ProcessInstance pi = new ProcessInstance( pd );
    pi.signal();
    Token root = pi.getRootToken();
    assertNotNull( root );

    Token firstToken = root.getChild( "first" );
    assertNotNull( firstToken );
    assertSame( pd.getNode("a"), firstToken.getNode() );

    Token secondToken = root.getChild( "second" );
    assertNotNull( secondToken );
    assertSame( pd.getNode("b"), secondToken.getNode() );
  }
}

流程定义文件:

xml 代码

<process-definition>
    <start-state name='start'>
        <transition to='and' />
    <!---->start-state>
    <fork name='and'>
        <transition name='first' to='a' />
        <transition name='second' to='b' />
    <!---->fork>
    <state name='a' />
    <state name='b' />
<!---->process-definition>"

         节点流程      start --> and -->  a
                                                     -- >  b

        本例中and --a   , and --> b  一定回被执行. 所以判断如下
         Token firstToken = root.getChild( "first" );
          assertNotNull( firstToken );

        并行分支 (AND-Split ) 多以 同步聚合((Synchronization)  结束.

同步聚合（Synchronization）

Description  : A point in the workow process where multiple parallel subprocesses/activities converge into one single thread of control, thus synchronizing multiple threads. It is an assumption of this pattern that each incoming branch of a synchronizer is executed only once

描述:            一个汇聚点, 多路工作流成执行线程汇聚成单个工作流执行线程. 只有汇聚线程都执行完毕,改汇聚点聚合后的单一线程才会执行.       

同义词:      AND-join, rendezvous, synchronizer.

java 代码

/*
 * JBoss, Home of Professional Open Source
 * Copyright 2005, JBoss Inc., and individual contributors as indicated
 * by the @authors tag. See the copyright.txt in the distribution for a
 * full listing of individual contributors.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */
package org.jbpm.jpdl.patterns;

import junit.framework.*;

import org.jbpm.graph.def.*;
import org.jbpm.graph.exe.*;

/**
 * http://is.tm.tue.nl/research/patterns/download/swf/pat_3.swf
 */
public class Wfp03SynchronizationTest extends TestCase {

  public ProcessDefinition createSynchronizationProcessDefinition() {
    ProcessDefinition pd = ProcessDefinition.parseXmlString(
      "
    <process-definition>"</process-definition>
     +
      "   +
      "     +
      "  " +
      "   +
      "     +
      "     +
      "  " +
      "   +
      "     +
      "  " +
      "   +
      "     +
      "  " +
      "   +
      "     +
      "  " +
      "   +
      ""
    );
    return pd;
  }

  public void testSynchronizationFirstTokenFirst() {
    ProcessDefinition pd = createSynchronizationProcessDefinition();

    ProcessInstance pi = new ProcessInstance( pd );
    pi.signal();
    Token root = pi.getRootToken();
    Token firstToken = root.getChild( "first" );
    Token secondToken = root.getChild( "second" );

    // check that the two tokens are in the states one and two respectively
    assertSame( pd.getNode("fork"), root.getNode() );
    assertSame( pd.getNode("one"), firstToken.getNode() );
    assertSame( pd.getNode("two"), secondToken.getNode() );

    firstToken.signal();
    assertSame( pd.getNode("fork"), root.getNode() );
    assertSame( pd.getNode("join"), firstToken.getNode() );
    assertSame( pd.getNode("two"), secondToken.getNode() );

    secondToken.signal();
    assertSame( pd.getNode("end"), root.getNode() );
    assertSame( pd.getNode("join"), firstToken.getNode() );
    assertSame( pd.getNode("join"), secondToken.getNode() );
  }

  /**
   * variation of the pattern where the second token fires first.
   */
  public void testSynchronizationSecondTokenFirst() {
    ProcessDefinition pd = createSynchronizationProcessDefinition();

    ProcessInstance pi = new ProcessInstance( pd );
    pi.signal();
    Token root = pi.getRootToken();
    Token firstToken = root.getChild( "first" );
    Token secondToken = root.getChild( "second" );

    // check that the two tokens are in the states one and two respectively
    assertSame( pd.getNode("fork"), root.getNode() );
    assertSame( pd.getNode("one"), firstToken.getNode() );
    assertSame( pd.getNode("two"), secondToken.getNode() );

    secondToken.signal();
    assertSame( pd.getNode("fork"), root.getNode() );
    assertSame( pd.getNode("one"), firstToken.getNode() );
    assertSame( pd.getNode("join"), secondToken.getNode() );

    firstToken.signal();
    assertSame( pd.getNode("end"), root.getNode() );
    assertSame( pd.getNode("join"), firstToken.getNode() );
    assertSame( pd.getNode("join"), secondToken.getNode() );
  }

  /**
   * nested form of the synchronization pattern.
   */
  public ProcessDefinition createNestedSynchronizationProcessDefinition() {
    // tip : draw this visually if you want to understand it.
    ProcessDefinition pd = new ProcessDefinition(
      new String[]{"start-state start",
                   "fork fork",
                   "fork fork1",
                   "fork fork2",
                   "state state1.1",
                   "state state1.2",
                   "state state2.1",
                   "state state2.2",
                   "join join2",
                   "join join1",
                   "join join",
                   "end-state end"},
      new String[]{"start --> fork",
                   "fork --first--> fork1",
                   "fork --second--> fork2",
                   "fork1 --first--> state1.1",
                   "fork1 --second--> state1.2",
                   "fork2 --first--> state2.1",
                   "fork2 --second--> state2.2",
                   "state1.1 --> join1",
                   "state1.2 --> join1",
                   "state2.1 --> join2",
                   "state2.2 --> join2",
                   "join1 --> join",
                   "join2 --> join",
                   "join --> end"});
    return pd;
  }

  public void testSynchronizationNested() {
    ProcessDefinition pd = createNestedSynchronizationProcessDefinition();
    ProcessInstance pi = new ProcessInstance( pd );
    pi.signal();
    Token rootToken = pi.getRootToken();
    Token token1 = rootToken.getChild( "first" );
    Token token2 = rootToken.getChild( "second" );
    Token token11 = token1.getChild( "first" );
    Token token12 = token1.getChild( "second" );
    Token token21 = token2.getChild( "first" );
    Token token22 = token2.getChild( "second" );

    assertSame( pd.getNode("fork"), rootToken.getNode() );
    assertSame( pd.getNode("fork1"), token1.getNode() );
    assertSame( pd.getNode("fork2"), token2.getNode() );
    assertSame( pd.getNode("state1.1"), token11.getNode() );
    assertSame( pd.getNode("state1.2"), token12.getNode() );
    assertSame( pd.getNode("state2.1"), token21.getNode() );
    assertSame( pd.getNode("state2.2"), token22.getNode() );

    token11.signal();

    assertSame( pd.getNode("fork"), rootToken.getNode() );
    assertSame( pd.getNode("fork1"), token1.getNode() );
    assertSame( pd.getNode("fork2"), token2.getNode() );
    assertSame( pd.getNode("join1"), token11.getNode() );
    assertSame( pd.getNode("state1.2"), token12.getNode() );
    assertSame( pd.getNode("state2.1"), token21.getNode() );
    assertSame( pd.getNode("state2.2"), token22.getNode() );

    token12.signal();

    assertSame( pd.getNode("fork"), rootToken.getNode() );
    assertSame( pd.getNode("join"), token1.getNode() );
    assertSame( pd.getNode("fork2"), token2.getNode() );
    assertSame( pd.getNode("join1"), token11.getNode() );
    assertSame( pd.getNode("join1"), token12.getNode() );
    assertSame( pd.getNode("state2.1"), token21.getNode() );
    assertSame( pd.getNode("state2.2"), token22.getNode() );

    token21.signal();

    assertSame( pd.getNode("fork"), rootToken.getNode() );
    assertSame( pd.getNode("join"), token1.getNode() );
    assertSame( pd.getNode("fork2"), token2.getNode() );
    assertSame( pd.getNode("join1"), token11.getNode() );
    assertSame( pd.getNode("join1"), token12.getNode() );
    assertSame( pd.getNode("join2"), token21.getNode() );
    assertSame( pd.getNode("state2.2"), token22.getNode() );

    token22.signal();

    assertSame( pd.getNode("end"), rootToken.getNode() );
    assertSame( pd.getNode("join"), token1.getNode() );
    assertSame( pd.getNode("join"), token2.getNode() );
    assertSame( pd.getNode("join1"), token11.getNode() );
    assertSame( pd.getNode("join1"), token12.getNode() );
    assertSame( pd.getNode("join2"), token21.getNode() );
    assertSame( pd.getNode("join2"), token22.getNode() );
  }
}