Activiti源码跟踪之模型Model操作

模型model设计到的表ACT_RE_MODEL、ACT_GE_BYTEARRAY

ACT_RE_MODEL表结构：

java 复制代码

CREATE TABLE `ACT_RE_MODEL` (
  `ID_` varchar(64) COLLATE utf8_bin NOT NULL,
  `REV_` int(11) DEFAULT NULL,
  `NAME_` varchar(255) COLLATE utf8_bin DEFAULT NULL,
  `KEY_` varchar(255) COLLATE utf8_bin DEFAULT NULL,
  `CATEGORY_` varchar(255) COLLATE utf8_bin DEFAULT NULL,
  `CREATE_TIME_` timestamp NULL DEFAULT NULL,
  `LAST_UPDATE_TIME_` timestamp NULL DEFAULT NULL,
  `VERSION_` int(11) DEFAULT NULL,
  `META_INFO_` varchar(4000) COLLATE utf8_bin DEFAULT NULL,
  `DEPLOYMENT_ID_` varchar(64) COLLATE utf8_bin DEFAULT NULL,
  `EDITOR_SOURCE_VALUE_ID_` varchar(64) COLLATE utf8_bin DEFAULT NULL,
  `EDITOR_SOURCE_EXTRA_VALUE_ID_` varchar(64) COLLATE utf8_bin DEFAULT NULL,
  `TENANT_ID_` varchar(255) COLLATE utf8_bin DEFAULT '',
  PRIMARY KEY (`ID_`),
  KEY `ACT_FK_MODEL_SOURCE` (`EDITOR_SOURCE_VALUE_ID_`),
  KEY `ACT_FK_MODEL_SOURCE_EXTRA` (`EDITOR_SOURCE_EXTRA_VALUE_ID_`),
  KEY `ACT_FK_MODEL_DEPLOYMENT` (`DEPLOYMENT_ID_`),
  CONSTRAINT `ACT_FK_MODEL_DEPLOYMENT` FOREIGN KEY (`DEPLOYMENT_ID_`) REFERENCES `ACT_RE_DEPLOYMENT` (`ID_`),
  CONSTRAINT `ACT_FK_MODEL_SOURCE` FOREIGN KEY (`EDITOR_SOURCE_VALUE_ID_`) REFERENCES `ACT_GE_BYTEARRAY` (`ID_`),
  CONSTRAINT `ACT_FK_MODEL_SOURCE_EXTRA` FOREIGN KEY (`EDITOR_SOURCE_EXTRA_VALUE_ID_`) REFERENCES `ACT_GE_BYTEARRAY` (`ID_`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_bin;

其中ACT_RE_MODEL有三个外键，对应ACT_GE_BYTEARRAY的有两个。

java 复制代码

CREATE TABLE `ACT_GE_BYTEARRAY`  (
  `ID_` varchar(64) CHARACTER SET utf8 COLLATE utf8_bin NOT NULL,
  `REV_` int NULL DEFAULT NULL,
  `NAME_` varchar(255) CHARACTER SET utf8 COLLATE utf8_bin NULL DEFAULT NULL,
  `DEPLOYMENT_ID_` varchar(64) CHARACTER SET utf8 COLLATE utf8_bin NULL DEFAULT NULL,
  `BYTES_` longblob NULL,
  `GENERATED_` tinyint NULL DEFAULT NULL,
  PRIMARY KEY (`ID_`) USING BTREE,
  INDEX `ACT_FK_BYTEARR_DEPL`(`DEPLOYMENT_ID_`) USING BTREE,
  CONSTRAINT `ACT_FK_BYTEARR_DEPL` FOREIGN KEY (`DEPLOYMENT_ID_`) REFERENCES `ACT_RE_DEPLOYMENT` (`ID_`) ON DELETE RESTRICT ON UPDATE RESTRICT
) ENGINE = InnoDB CHARACTER SET = utf8 COLLATE = utf8_bin ROW_FORMAT = Dynamic;

EDITOR_SOURCE_VALUE_ID_对应ACT_GE_BYTEARRAY的ID_，表示该模型对应的模型文件（json格式数据）。repositoryService.addModelEditorSource方法实现。

EDITOR_SOURCE_EXTRA_VALUE_ID_对应ACT_GE_BYTEARRAY的ID_，表示该模型生成的图片文件。repositoryService.addModelEditorSourceExtra方法实现。

1、保存模型：

Model modelData = repositoryService.newModel();

repositoryService.saveModel(modelData);

执行对应的SaveModelCmd。会插入或更新ACT_RE_MODEL的数据。

SaveModelCmd对应的execute方法：

java 复制代码

public Void execute(CommandContext commandContext) {
    if(model == null) {
      throw new ActivitiIllegalArgumentException("model is null");
    }
    if (model.getId() == null) {
      commandContext.getModelEntityManager().insertModel(model);
    } else {
      commandContext.getModelEntityManager().updateModel(model);
    }
    return null;
  }

执行对应的insert或update方法：

insert方法分发ENTITY_CREATED和ENTITY_INITIALIZED事件：

java 复制代码

  public void insertModel(Model model) {
    ((ModelEntity) model).setCreateTime(Context.getProcessEngineConfiguration().getClock().getCurrentTime());
    ((ModelEntity) model).setLastUpdateTime(Context.getProcessEngineConfiguration().getClock().getCurrentTime());
    getDbSqlSession().insert((PersistentObject) model);
    
    if(Context.getProcessEngineConfiguration().getEventDispatcher().isEnabled()) {
    	Context.getProcessEngineConfiguration().getEventDispatcher().dispatchEvent(
    			ActivitiEventBuilder.createEntityEvent(ActivitiEventType.ENTITY_CREATED, model));
    	Context.getProcessEngineConfiguration().getEventDispatcher().dispatchEvent(
    			ActivitiEventBuilder.createEntityEvent(ActivitiEventType.ENTITY_INITIALIZED, model));
    }
  }

update方法分发ENTITY_UPDATED方法：

java 复制代码

public void updateModel(ModelEntity updatedModel) {
    CommandContext commandContext = Context.getCommandContext();
    updatedModel.setLastUpdateTime(Context.getProcessEngineConfiguration().getClock().getCurrentTime());
    DbSqlSession dbSqlSession = commandContext.getDbSqlSession();
    dbSqlSession.update(updatedModel);
    
    if(Context.getProcessEngineConfiguration().getEventDispatcher().isEnabled()) {
    	Context.getProcessEngineConfiguration().getEventDispatcher().dispatchEvent(
    			ActivitiEventBuilder.createEntityEvent(ActivitiEventType.ENTITY_UPDATED, updatedModel));
    }
  }

2、保存其他信息（模型文件或图片）

保存模型文件（json格式）。涉及到的表：ACT_RE_MODEL、ACT_GE_BYTEARRAY

java 复制代码

repositoryService.addModelEditorSource(modelData.getId(), editorNode.toString().getBytes("utf-8"));

AddEditorSourceForModelCmd：

java 复制代码

public Object execute(CommandContext commandContext) {
    commandContext
      .getModelEntityManager()
      .insertEditorSourceForModel(modelId, bytes);
    
    return null;
  }
}

insertEditorSourceForModel

java 复制代码

public void insertEditorSourceForModel(String modelId, byte[] modelSource) {
    ModelEntity model = findModelById(modelId);
    if (model != null) {
      ByteArrayRef ref = new ByteArrayRef(model.getEditorSourceValueId());
      ref.setValue("source", modelSource);
      
      if (model.getEditorSourceValueId() == null) {
        model.setEditorSourceValueId(ref.getId());
        updateModel(model);
      }
    }
  }

其中ref.setValue("source", modelSource)方法对

model.getEditorSourceValueId() == null 生成DbSqlSession的inser语句，最后执行updateModel方法

model.getEditorSourceValueId() != null ，ByteArrayRef.ensureInitialized()方法调用DbSqlSession.selectById()，ByteArrayEntity存放在canche。ByteArrayRef.setBytes(bytes); 把新的byte值设进 ByteArrayEntity

DbSqlSession.flush()的getUpdatedObjects()方法，比较persistentObject对象，生成update