问题来源
非常感谢@doctorwho的问题：
假如职业介绍所来了一批生产汽车的工作，假设生产一辆汽车任务是这样的：搭好底盘、拧4个轮胎、安装发动机、安装4个座椅、再装4个车门、最后安装顶棚。之间有的任务是可以并行计算的（比如拧4个轮胎，安装发动机和安装座椅），有的任务有前置任务（比如先装好座椅，才能装车门和顶棚）。让两组包工头组织两种类型的工作：将工人分成两种类型,即可并行计算的放在同一组内，由职业介绍所来控制A组包工头做完的任务交给B组包工头。中间环节的半成品保存到Warehouse中，是这样使用TINY框架来生产汽车么？
接下来，我就用Tiny并行计算框架来展示一下这个示例，在编写示例的时候，发现了一个BUG，这也充分体现了开源的精神与价值，再次感谢@doctorwho。
问题分析
doctorwho的问题还是比较复杂的，但是实际上道理是一样的，因此我把问题简化成下面的过程
第一步：构建底盘
第二步：并行进行安装引擎，座位和轮胎
第三步：并行进行安装门及车顶
由于我和doctorwho都不是造车行家，因此就不用纠结这么造是不是合理了，假设这么做就是合理的。
代码实现
按我前面说的过程，工人是必须要有的，因此我们首先构建工人：
第一步的底盘构建工人
1public class StepFirstWorker extends AbstractWorker { 2 public StepFirstWorker() throws RemoteException { 3 super("first"); 4 } 5 6 @Override 7 protected Warehouse doWork(Work work) throws RemoteException { 8 System.out.println(String.format("%s 构建底盘完成.", work.getInputWarehouse().get("carType"))); 9 Warehouse outputWarehouse = work.getInputWarehouse(); 10 outputWarehouse.put("baseInfo", "something about baseInfo"); 11 return outputWarehouse; 12 } 13}
由于第二步工人有好几个类型，因此再搞个第二步抽象工人：
1public abstract class StepThirdWorker extends AbstractWorker { 2 public StepThirdWorker() throws RemoteException { 3 super("third"); 4 } 5 6 7 protected boolean acceptMyWork(Work work) { 8 String workClass = work.getInputWarehouse().get("class"); 9 if (workClass != null) { 10 return true; 11 } 12 return false; 13 } 14 protected Warehouse doMyWork(Work work) throws RemoteException { 15 System.out.println(String.format("Base:%s ", work.getInputWarehouse().get("baseInfo"))); 16 System.out.println(String.format("%s is Ok", work.getInputWarehouse().get("class"))); 17 return work.getInputWarehouse(); 18 } 19}
接下来构建第二步的引擎工人：
1public class StepSecondEngineWorker extends StepSecondWorker { 2 3 4 public static final String ENGINE = "engine"; 5 6 7 public StepSecondEngineWorker() throws RemoteException { 8 super(); 9 } 10 11 12 public boolean acceptWork(Work work) { 13 return acceptMyWork(work); 14 } 15 16 17 protected Warehouse doWork(Work work) throws RemoteException { 18 return super.doMyWork(work); 19 } 20}
第二步的座位工人：
1public class StepSecondSeatWorker extends StepSecondWorker { 2 3 4 public static final String SEAT = "seat"; 5 6 7 public StepSecondSeatWorker() throws RemoteException { 8 super(); 9 } 10 public boolean acceptWork(Work work) { 11 return acceptMyWork(work); 12 } 13 protected Warehouse doWork(Work work) throws RemoteException { 14 return super.doMyWork(work); 15 } 16} 17 18 19 20 21 22 23 24 25 26 27
第二步的轮胎工人：
1public class StepSecondTyreWorker extends StepSecondWorker { 2 public static final String TYRE = "tyre"; 3 4 5 public StepSecondTyreWorker() throws RemoteException { 6 super(); 7 } 8 9 10 public boolean acceptWork(Work work) { 11 return acceptMyWork(work); 12 } 13 14 15 protected Warehouse doWork(Work work) throws RemoteException { 16 return super.doMyWork(work); 17 } 18}
同理，第三步也是大同小异的。
第三步的抽象工人类：
1public abstract class StepThirdWorker extends AbstractWorker { 2 public StepThirdWorker() throws RemoteException { 3 super("third"); 4 } 5 6 7 protected boolean acceptMyWork(Work work) { 8 String workClass = work.getInputWarehouse().get("class"); 9 if (workClass != null) { 10 return true; 11 } 12 return false; 13 } 14 protected Warehouse doMyWork(Work work) throws RemoteException { 15 System.out.println(String.format("Base:%s ", work.getInputWarehouse().get("baseInfo"))); 16 System.out.println(String.format("%s is Ok", work.getInputWarehouse().get("class"))); 17 return work.getInputWarehouse(); 18 } 19}
第三步的车门工人：
1public class StepThirdDoorWorker extends StepThirdWorker { 2 3 4 public static final String DOOR = "door"; 5 6 7 public StepThirdDoorWorker() throws RemoteException { 8 super(); 9 } 10 public boolean acceptWork(Work work) { 11 return acceptMyWork(work); 12 } 13 @Override 14 protected Warehouse doWork(Work work) throws RemoteException { 15 return super.doMyWork(work); 16 } 17}
第三步的车顶工人：
1public class StepThirdRoofWorker extends StepThirdWorker { 2 3 4 public static final String ROOF = "roof"; 5 6 7 public StepThirdRoofWorker() throws RemoteException { 8 super(); 9 } 10 public boolean acceptWork(Work work) { 11 return acceptMyWork(work); 12 } 13 protected Warehouse doWork(Work work) throws RemoteException { 14 return super.doMyWork(work); 15 } 16}
以上就把工人都构建好了，我们前面也说过，如果要进行任务分解，是必须要构建任务分解合并器的，这里简单起见，只实现任务分解了。
第二部的任务分解：
1public class SecondWorkSplitter implements WorkSplitter { 2 public List<Warehouse> split(Work work, List<Worker> workers) throws RemoteException { 3 List<Warehouse> list = new ArrayList<Warehouse>(); 4 list.add(getWareHouse(work.getInputWarehouse(), "engine")); 5 list.add(getWareHouse(work.getInputWarehouse(), "seat")); 6 list.add(getWareHouse(work.getInputWarehouse(), "seat")); 7 list.add(getWareHouse(work.getInputWarehouse(), "seat")); 8 list.add(getWareHouse(work.getInputWarehouse(), "seat")); 9 list.add(getWareHouse(work.getInputWarehouse(), "tyre")); 10 list.add(getWareHouse(work.getInputWarehouse(), "tyre")); 11 list.add(getWareHouse(work.getInputWarehouse(), "tyre")); 12 list.add(getWareHouse(work.getInputWarehouse(), "tyre")); 13 return list; 14 } 15 16 private Warehouse getWareHouse(Warehouse inputWarehouse, String stepClass) { 17 Warehouse warehouse = new WarehouseDefault(); 18 warehouse.put("class", stepClass); 19 warehouse.putSubWarehouse(inputWarehouse); 20 return warehouse; 21 } 22}
从上面可以看到，构建了一个引擎的仓库，4个座位仓库，4个轮胎仓库。呵呵，既然能并行，为啥不让他做得更快些？
接下来是第三步的任务分解器：
1public class ThirdWorkSplitter implements WorkSplitter { 2 public List<Warehouse> split(Work work, List<Worker> workers) throws RemoteException { 3 List<Warehouse> list = new ArrayList<Warehouse>(); 4 list.add(getWareHouse(work.getInputWarehouse(), "door")); 5 list.add(getWareHouse(work.getInputWarehouse(), "door")); 6 list.add(getWareHouse(work.getInputWarehouse(), "door")); 7 list.add(getWareHouse(work.getInputWarehouse(), "door")); 8 list.add(getWareHouse(work.getInputWarehouse(), "roof")); 9 return list; 10 } 11 12 private Warehouse getWareHouse(Warehouse inputWarehouse, String stepClass) { 13 Warehouse warehouse = new WarehouseDefault(); 14 warehouse.put("class", stepClass); 15 warehouse.putSubWarehouse(inputWarehouse); 16 return warehouse; 17 } 18}
从上面可以看到，第三部构建了4个门仓库一个车顶仓库，同样的，可以让4个工人同时装门。
上面就把所有的准备工作都做好了，接下来就是测试方法了：
1public class Test { 2 public static void main(String[] args) throws IOException, ClassNotFoundException, InterruptedException { 3 JobCenter jobCenter = new JobCenterLocal(); 4 5 6 for (int i = 0; i < 5; i++) { 7 jobCenter.registerWorker(new StepFirstWorker()); 8 } 9 for (int i = 0; i < 5; i++) { 10 jobCenter.registerWorker(new StepSecondTyreWorker()); 11 } 12 for (int i = 0; i < 5; i++) { 13 jobCenter.registerWorker(new StepSecondSeatWorker()); 14 } 15 for (int i = 0; i < 5; i++) { 16 jobCenter.registerWorker(new StepSecondEngineWorker()); 17 } 18 for (int i = 0; i < 5; i++) { 19 jobCenter.registerWorker(new StepThirdDoorWorker()); 20 } 21 for (int i = 0; i < 5; i++) { 22 jobCenter.registerWorker(new StepThirdRoofWorker()); 23 } 24 25 jobCenter.registerForeman(new ForemanSelectOneWorker("first")); 26 jobCenter.registerForeman(new ForemanSelectAllWorker("second", 27 new SecondWorkSplitter())); 28 jobCenter.registerForeman(new ForemanSelectAllWorker("third",new ThirdWorkSplitter())); 29 30 31 Warehouse inputWarehouse = new WarehouseDefault(); 32 inputWarehouse.put("class", "car"); 33 inputWarehouse.put("carType", "普桑"); 34 WorkDefault work = new WorkDefault("first", inputWarehouse); 35 work.setForemanType("first"); 36 WorkDefault work2 = new WorkDefault("second"); 37 work2.setForemanType("second"); 38 WorkDefault work3 = new WorkDefault("third"); 39 work3.setForemanType("third"); 40 work.setNextWork(work2).setNextWork(work3); 41 42 43 Warehouse warehouse = jobCenter.doWork(work); 44 45 46 jobCenter.stop(); 47 48 } 49}
呵呵，工人各加了5个，然后注册了三个工头，第一步的工头是随便挑一个工人类型的，第二步和第三步是挑所有工人的，同时还指定了任务分解器。
接下来就构建了一个工作，造一个高端大气上档次的普桑汽车，然后告诉职业介绍所说给我造就可以了。
下面是造车的过程，我把日志也贴上来了：
1普桑 构建底盘完成. 2-234 [RMI TCP Connection(1)-192.168.84.73] INFO - 线程组<id:4af96b81d14a4954a6b649308d444e4c,type:second>运行开始,线程数9... 3-234 [id:4af96b81d14a4954a6b649308d444e4c,type:second-a763f156ffd74b5db285198d2498edcf] INFO - 线程<id:4af96b81d14a4954a6b649308d444e4c,type:second-a763f156ffd74b5db285198d2498edcf>运行开始... 4-234 [id:4af96b81d14a4954a6b649308d444e4c,type:second-c2d2fb38ef6c4509b3a39b3e7d5c1d61] INFO - 线程<id:4af96b81d14a4954a6b649308d444e4c,type:second-c2d2fb38ef6c4509b3a39b3e7d5c1d61>运行开始... 5-234 [id:4af96b81d14a4954a6b649308d444e4c,type:second-d624ea0a6df3409c80df6b97ab3c813b] INFO - 线程<id:4af96b81d14a4954a6b649308d444e4c,type:second-d624ea0a6df3409c80df6b97ab3c813b>运行开始... 6-235 [id:4af96b81d14a4954a6b649308d444e4c,type:second-abdb57f0641a4727a9efa744d07cf2d1] INFO - 线程<id:4af96b81d14a4954a6b649308d444e4c,type:second-abdb57f0641a4727a9efa744d07cf2d1>运行开始... 7-236 [id:4af96b81d14a4954a6b649308d444e4c,type:second-d6f7074f6c4a4b12bd37ec5f5c11aff8] INFO - 线程<id:4af96b81d14a4954a6b649308d444e4c,type:second-d6f7074f6c4a4b12bd37ec5f5c11aff8>运行开始... 8-237 [id:4af96b81d14a4954a6b649308d444e4c,type:second-04db3f945b804500a2bbe2b9aabdce3b] INFO - 线程<id:4af96b81d14a4954a6b649308d444e4c,type:second-04db3f945b804500a2bbe2b9aabdce3b>运行开始... 9Base:something about baseInfo 10engine is Ok 11Base:something about baseInfo 12seat is Ok 13-245 [id:4af96b81d14a4954a6b649308d444e4c,type:second-a763f156ffd74b5db285198d2498edcf] INFO - 线程<id:4af96b81d14a4954a6b649308d444e4c,type:second-a763f156ffd74b5db285198d2498edcf>运行结束 14-246 [id:4af96b81d14a4954a6b649308d444e4c,type:second-f3efba2dc7804c6cbcd5a25f42fdc177] INFO - 线程<id:4af96b81d14a4954a6b649308d444e4c,type:second-f3efba2dc7804c6cbcd5a25f42fdc177>运行开始... 15-246 [id:4af96b81d14a4954a6b649308d444e4c,type:second-abdb57f0641a4727a9efa744d07cf2d1] INFO - 线程<id:4af96b81d14a4954a6b649308d444e4c,type:second-abdb57f0641a4727a9efa744d07cf2d1>运行结束 16Base:something about baseInfo 17seat is Ok 18-248 [id:4af96b81d14a4954a6b649308d444e4c,type:second-8c3b9359bcfa4de7b6e0492daab0d73a] INFO - 线程<id:4af96b81d14a4954a6b649308d444e4c,type:second-8c3b9359bcfa4de7b6e0492daab0d73a>运行开始... 19Base:something about baseInfo 20tyre is Ok 21-250 [id:4af96b81d14a4954a6b649308d444e4c,type:second-f3efba2dc7804c6cbcd5a25f42fdc177] INFO - 线程<id:4af96b81d14a4954a6b649308d444e4c,type:second-f3efba2dc7804c6cbcd5a25f42fdc177>运行结束 22-250 [id:4af96b81d14a4954a6b649308d444e4c,type:second-c2d2fb38ef6c4509b3a39b3e7d5c1d61] INFO - 线程<id:4af96b81d14a4954a6b649308d444e4c,type:second-c2d2fb38ef6c4509b3a39b3e7d5c1d61>运行结束 23Base:something about baseInfo 24seat is Ok 25-252 [id:4af96b81d14a4954a6b649308d444e4c,type:second-869b573e226046aca8ad30765f1f300c] INFO - 线程<id:4af96b81d14a4954a6b649308d444e4c,type:second-869b573e226046aca8ad30765f1f300c>运行开始... 26-253 [id:4af96b81d14a4954a6b649308d444e4c,type:second-8c3b9359bcfa4de7b6e0492daab0d73a] INFO - 线程<id:4af96b81d14a4954a6b649308d444e4c,type:second-8c3b9359bcfa4de7b6e0492daab0d73a>运行结束 27Base:something about baseInfo 28seat is Ok 29Base:something about baseInfo 30tyre is Ok 31-257 [id:4af96b81d14a4954a6b649308d444e4c,type:second-d624ea0a6df3409c80df6b97ab3c813b] INFO - 线程<id:4af96b81d14a4954a6b649308d444e4c,type:second-d624ea0a6df3409c80df6b97ab3c813b>运行结束 32-258 [id:4af96b81d14a4954a6b649308d444e4c,type:second-04db3f945b804500a2bbe2b9aabdce3b] INFO - 线程<id:4af96b81d14a4954a6b649308d444e4c,type:second-04db3f945b804500a2bbe2b9aabdce3b>运行结束 33Base:something about baseInfo 34tyre is Ok 35Base:something about baseInfo 36tyre is Ok 37-262 [id:4af96b81d14a4954a6b649308d444e4c,type:second-869b573e226046aca8ad30765f1f300c] INFO - 线程<id:4af96b81d14a4954a6b649308d444e4c,type:second-869b573e226046aca8ad30765f1f300c>运行结束 38-264 [id:4af96b81d14a4954a6b649308d444e4c,type:second-d6f7074f6c4a4b12bd37ec5f5c11aff8] INFO - 线程<id:4af96b81d14a4954a6b649308d444e4c,type:second-d6f7074f6c4a4b12bd37ec5f5c11aff8>运行结束 39-264 [RMI TCP Connection(1)-192.168.84.73] INFO - 线程组<id:4af96b81d14a4954a6b649308d444e4c,type:second>运行结束, 用时:30ms 40-333 [RMI TCP Connection(1)-192.168.84.73] INFO - 线程组<id:9b0de678632d4fb8b87ae9db4b6436f8,type:third>运行开始,线程数5... 41-334 [id:9b0de678632d4fb8b87ae9db4b6436f8,type:third-ca58e9b733514c668a224875417c9d26] INFO - 线程<id:9b0de678632d4fb8b87ae9db4b6436f8,type:third-ca58e9b733514c668a224875417c9d26>运行开始... 42-334 [id:9b0de678632d4fb8b87ae9db4b6436f8,type:third-17debef817e34c49996a2c38840f3de2] INFO - 线程<id:9b0de678632d4fb8b87ae9db4b6436f8,type:third-17debef817e34c49996a2c38840f3de2>运行开始... 43-334 [id:9b0de678632d4fb8b87ae9db4b6436f8,type:third-af0e914cce89480987c6184a885770d5] INFO - 线程<id:9b0de678632d4fb8b87ae9db4b6436f8,type:third-af0e914cce89480987c6184a885770d5>运行开始... 44-334 [id:9b0de678632d4fb8b87ae9db4b6436f8,type:third-3f7707cb2a224d3d8844a09271b24a07] INFO - 线程<id:9b0de678632d4fb8b87ae9db4b6436f8,type:third-3f7707cb2a224d3d8844a09271b24a07>运行开始... 45Base:something about baseInfo 46door is Ok 47Base:something about baseInfo 48door is Ok 49Base:something about baseInfo 50-338 [id:9b0de678632d4fb8b87ae9db4b6436f8,type:third-ca58e9b733514c668a224875417c9d26] INFO - 线程<id:9b0de678632d4fb8b87ae9db4b6436f8,type:third-ca58e9b733514c668a224875417c9d26>运行结束 51door is Ok 52-339 [id:9b0de678632d4fb8b87ae9db4b6436f8,type:third-cfccfb37ebda4279b7552f7e060b2ddb] INFO - 线程<id:9b0de678632d4fb8b87ae9db4b6436f8,type:third-cfccfb37ebda4279b7552f7e060b2ddb>运行开始... 53-338 [id:9b0de678632d4fb8b87ae9db4b6436f8,type:third-17debef817e34c49996a2c38840f3de2] INFO - 线程<id:9b0de678632d4fb8b87ae9db4b6436f8,type:third-17debef817e34c49996a2c38840f3de2>运行结束 54Base:something about baseInfo 55door is Ok 56Base:something about baseInfo 57-340 [id:9b0de678632d4fb8b87ae9db4b6436f8,type:third-3f7707cb2a224d3d8844a09271b24a07] INFO - 线程<id:9b0de678632d4fb8b87ae9db4b6436f8,type:third-3f7707cb2a224d3d8844a09271b24a07>运行结束 58roof is Ok 59-340 [id:9b0de678632d4fb8b87ae9db4b6436f8,type:third-af0e914cce89480987c6184a885770d5] INFO - 线程<id:9b0de678632d4fb8b87ae9db4b6436f8,type:third-af0e914cce89480987c6184a885770d5>运行结束 60-342 [id:9b0de678632d4fb8b87ae9db4b6436f8,type:third-cfccfb37ebda4279b7552f7e060b2ddb] INFO - 线程<id:9b0de678632d4fb8b87ae9db4b6436f8,type:third-cfccfb37ebda4279b7552f7e060b2ddb>运行结束 61-343 [RMI TCP Connection(1)-192.168.84.73] INFO - 线程组<id:9b0de678632d4fb8b87ae9db4b6436f8,type:third>运行结束, 用时:10ms
从上面的日志可以看出：
由于第一步工作是挑一个单干的，因此是没有启用线程组的
第二步同时有9个线程干活：
1-234 [RMI TCP Connection(1)-192.168.84.73] INFO - 线程组<id:4af96b81d14a4954a6b649308d444e4c,type:second>运行开始,线程数9... 2... 3-264 [RMI TCP Connection(1)-192.168.84.73] INFO - 线程组<id:4af96b81d14a4954a6b649308d444e4c,type:second>运行结束, 用时:30ms
第三步同时有5个线程干活：
1-333 [RMI TCP Connection(1)-192.168.84.73] INFO - 线程组<id:9b0de678632d4fb8b87ae9db4b6436f8,type:third>运行开始,线程数5... 2... 3-343 [RMI TCP Connection(1)-192.168.84.73] INFO - 线程组<id:9b0de678632d4fb8b87ae9db4b6436f8,type:third>运行结束, 用时:10ms
总结：
Tiny并行计算框架确实是可以方便的解决各种复杂并行计算的问题。