01-activiti6基础——引擎如何数据库操作及相关表

官网文档：https://www.activiti.org/userguide/#queryAPI

1. Activit的简单源码解读

     activiti的官方文档讲解详细很详细，也很范。按着文档写完了一个简单的demo发现，现实中的大多数问题，还是没法很好的解决。

例如：首先我需要知道的是，activiti的有那些表，及各个表的作用。这个网上有人罗列过，但总是觉得不通透。

所以，我先简单看了一下activiti数据处理的源码。

1.1 流程发布

• RepositoryServiceImpl

进行对那个操作的封装，传递Command接口的对应子类，里面封装了具体的操作

  public Deployment deploy(DeploymentBuilderImpl deploymentBuilder) {
    return commandExecutor.execute(new DeployCmd<Deployment>(deploymentBuilder));
  }

• CommandInvoker

commandExecutor.execute() 这个方法的执行本质，是里面的CommandInterceptor执行链式的execute,而实质执行的是传进来的CMD接口类的execute方法。具体如下所示。

 public <T> T execute(final CommandConfig config, final Command<T> command) {
    final CommandContext commandContext = Context.getCommandContext();

    //省略一些代码

    commandContext.getAgenda().planOperation(new Runnable() {
      @Override
      public void run() {
        commandContext.setResult(command.execute(commandContext));//这里是关键
      }
    });

     // 省略一些代码。。。。。。。。。。。。

    return (T) commandContext.getResult();
  }

• DeployCmd(从这里调用DataManager的实现类进行相关数据库操作)

public Deployment execute(CommandContext commandContext) {

    // Backwards compatibility with Activiti v5
    if (commandContext.getProcessEngineConfiguration().isActiviti5CompatibilityEnabled()
        && deploymentBuilder.getDeploymentProperties() != null 
        && deploymentBuilder.getDeploymentProperties().containsKey(DeploymentProperties.DEPLOY_AS_ACTIVITI5_PROCESS_DEFINITION)
        && deploymentBuilder.getDeploymentProperties().get(DeploymentProperties.DEPLOY_AS_ACTIVITI5_PROCESS_DEFINITION).equals(Boolean.TRUE)) {
      
        return deployAsActiviti5ProcessDefinition(commandContext);
    }

    return executeDeploy(commandContext);
  }

• DeploymentEntityManagerImpl

实际数据库操作的是DataManager的实现类，进行数据库操作。

这个我们能看出来是有两个

 @Override
  public void insert(DeploymentEntity deployment) {
    insert(deployment, false);

    for (ResourceEntity resource : deployment.getResources().values()) {
      resource.setDeploymentId(deployment.getId());
      getResourceEntityManager().insert(resource);
    }
  }

• 对应的xml操作

在mapping目录下可以查找到对应的操作。前面的${prefix}标识数据库，activiti已经帮我们判断好了，不需要我们再传入。

  <insert id="insertDeployment" parameterType="org.activiti.engine.impl.persistence.entity.DeploymentEntityImpl">
    insert into ${prefix}ACT_RE_DEPLOYMENT(ID_, NAME_, CATEGORY_, KEY_, TENANT_ID_, DEPLOY_TIME_, ENGINE_VERSION_)
    values(#{id, jdbcType=VARCHAR}, #{name, jdbcType=VARCHAR}, #{category, jdbcType=VARCHAR}, #{key, jdbcType=VARCHAR}, #{tenantId, jdbcType=VARCHAR}, #{deploymentTime, jdbcType=TIMESTAMP}, #{engineVersion, jdbcType=VARCHAR})
  </insert>

<insert id="insertResource" parameterType="org.activiti.engine.impl.persistence.entity.ResourceEntityImpl">
    insert into ${prefix}ACT_GE_BYTEARRAY(ID_, REV_, NAME_, BYTES_, DEPLOYMENT_ID_, GENERATED_)
    values (#{id, jdbcType=VARCHAR}, 1, #{name, jdbcType=VARCHAR}, #{bytes, jdbcType=${blobType}}, #{deploymentId, jdbcType=VARCHAR}, #{generated, jdbcType=BOOLEAN})  
  </insert>

1.2 数据查询

• DataManager

数据查询操作本质都是通过DataManger的实现类MybatisDeploymentDataManager进行操作；

  @Override
  public List<Deployment> executeList(CommandContext commandContext, Page page) {
    checkQueryOk();
    return commandContext.getDeploymentEntityManager().findDeploymentsByQueryCriteria(this, page);
  }

  @Override
  @SuppressWarnings("unchecked")
  public List<Deployment> findDeploymentsByQueryCriteria(DeploymentQueryImpl deploymentQuery, Page page) {
    final String query = "selectDeploymentsByQueryCriteria";
    return getDbSqlSession().selectList(query, deploymentQuery, page);
  }    

• 查找xml中对应的sql

  <select id="selectDeploymentsByQueryCriteria" parameterType="org.activiti.engine.impl.DeploymentQueryImpl" resultMap="deploymentResultMap">
  	${limitBefore}
    select distinct RES.* ${limitBetween}
    <include refid="selectDeploymentsByQueryCriteriaSql"/>
    ${orderBy}
    ${limitAfter}
  </select>

1.3 任务执行

需要了解任务类型，以及网关相关知识。

• TaskService

taskService.complete(task.getId(), taskVariables);

• AbstractCompleteTaskCmd

protected void executeTaskComplete(CommandContext commandContext, TaskEntity taskEntity, Map<String, Object> variables, boolean localScope) {
    // Task complete logic

    if (taskEntity.getDelegationState() != null && taskEntity.getDelegationState().equals(DelegationState.PENDING)) {
      throw new ActivitiException("A delegated task cannot be completed, but should be resolved instead.");
    }
    //执行节点监听事件  
    commandContext.getProcessEngineConfiguration().getListenerNotificationHelper().executeTaskListeners(taskEntity, TaskListener.EVENTNAME_COMPLETE);
    if (Authentication.getAuthenticatedUserId() != null && taskEntity.getProcessInstanceId() != null) {
       //查找任务select * from ${prefix}ACT_RU_EXECUTION
       // where ROOT_PROC_INST_ID_ = (select ROOT_PROC_INST_ID_ from ${prefix}ACT_RU_EXECUTION where ID_ = #{parameter})
      ExecutionEntity processInstanceEntity = commandContext.getExecutionEntityManager().findById(taskEntity.getProcessInstanceId());
      //任务和identity绑定
      commandContext.getIdentityLinkEntityManager().involveUser(processInstanceEntity, Authentication.getAuthenticatedUserId(),IdentityLinkType.PARTICIPANT);
    }

    ActivitiEventDispatcher eventDispatcher = Context.getProcessEngineConfiguration().getEventDispatcher();
    if (eventDispatcher.isEnabled()) {
      if (variables != null) {
        eventDispatcher.dispatchEvent(ActivitiEventBuilder.createEntityWithVariablesEvent(ActivitiEventType.TASK_COMPLETED, taskEntity, variables, localScope));
      } else {
        eventDispatcher.dispatchEvent(ActivitiEventBuilder.createEntityEvent(ActivitiEventType.TASK_COMPLETED, taskEntity));
      }
    }
      //删除已有的任务相关数据
    commandContext.getTaskEntityManager().deleteTask(taskEntity, null, false, false);

    // Continue process (if not a standalone task) 激活下个步骤工作
    if (taskEntity.getExecutionId() != null) {
      ExecutionEntity executionEntity = commandContext.getExecutionEntityManager().findById(taskEntity.getExecutionId());
      Context.getAgenda().planTriggerExecutionOperation(executionEntity);
    }
  }

1.4 获取类对应表名称

ManagementService

  managementService.getTableName()

TableDataManagerImpl

static {
    // runtime
    entityToTableNameMap.put(TaskEntity.class, "ACT_RU_TASK");
    entityToTableNameMap.put(ExecutionEntity.class, "ACT_RU_EXECUTION");
    entityToTableNameMap.put(IdentityLinkEntity.class, "ACT_RU_IDENTITYLINK");
    entityToTableNameMap.put(VariableInstanceEntity.class, "ACT_RU_VARIABLE");

    entityToTableNameMap.put(JobEntity.class, "ACT_RU_JOB");
    entityToTableNameMap.put(TimerJobEntity.class, "ACT_RU_TIMER_JOB");
    entityToTableNameMap.put(SuspendedJobEntity.class, "ACT_RU_SUSPENDED_JOB");
    entityToTableNameMap.put(DeadLetterJobEntity.class, "ACT_RU_DEADLETTER_JOB");
    

    entityToTableNameMap.put(EventSubscriptionEntity.class, "ACT_RU_EVENT_SUBSCR");
    entityToTableNameMap.put(CompensateEventSubscriptionEntity.class, "ACT_RU_EVENT_SUBSCR");
    entityToTableNameMap.put(MessageEventSubscriptionEntity.class, "ACT_RU_EVENT_SUBSCR");
    entityToTableNameMap.put(SignalEventSubscriptionEntity.class, "ACT_RU_EVENT_SUBSCR");

    // repository
    entityToTableNameMap.put(DeploymentEntity.class, "ACT_RE_DEPLOYMENT");
    entityToTableNameMap.put(ProcessDefinitionEntity.class, "ACT_RE_PROCDEF");
    entityToTableNameMap.put(ModelEntity.class, "ACT_RE_MODEL");
    entityToTableNameMap.put(ProcessDefinitionInfoEntity.class, "ACT_PROCDEF_INFO");

    // history
    entityToTableNameMap.put(CommentEntity.class, "ACT_HI_COMMENT");

    entityToTableNameMap.put(HistoricActivityInstanceEntity.class, "ACT_HI_ACTINST");
    entityToTableNameMap.put(AttachmentEntity.class, "ACT_HI_ATTACHMENT");
    entityToTableNameMap.put(HistoricProcessInstanceEntity.class, "ACT_HI_PROCINST");
    entityToTableNameMap.put(HistoricVariableInstanceEntity.class, "ACT_HI_VARINST");
    entityToTableNameMap.put(HistoricTaskInstanceEntity.class, "ACT_HI_TASKINST");
    entityToTableNameMap.put(HistoricIdentityLinkEntity.class, "ACT_HI_IDENTITYLINK");

    // a couple of stuff goes to the same table
    entityToTableNameMap.put(HistoricDetailAssignmentEntity.class, "ACT_HI_DETAIL");
    entityToTableNameMap.put(HistoricDetailTransitionInstanceEntity.class, "ACT_HI_DETAIL");
    entityToTableNameMap.put(HistoricFormPropertyEntity.class, "ACT_HI_DETAIL");
    entityToTableNameMap.put(HistoricDetailVariableInstanceUpdateEntity.class, "ACT_HI_DETAIL");
    entityToTableNameMap.put(HistoricDetailEntity.class, "ACT_HI_DETAIL");

    // Identity module
    entityToTableNameMap.put(GroupEntity.class, "ACT_ID_GROUP");
    entityToTableNameMap.put(MembershipEntity.class, "ACT_ID_MEMBERSHIP");
    entityToTableNameMap.put(UserEntity.class, "ACT_ID_USER");
    entityToTableNameMap.put(IdentityInfoEntity.class, "ACT_ID_INFO");

    // general
    entityToTableNameMap.put(PropertyEntity.class, "ACT_GE_PROPERTY");
    entityToTableNameMap.put(ByteArrayEntity.class, "ACT_GE_BYTEARRAY");
    entityToTableNameMap.put(ResourceEntity.class, "ACT_GE_BYTEARRAY");
    
    entityToTableNameMap.put(EventLogEntryEntity.class, "ACT_EVT_LOG");

    // and now the map for the API types (does not cover all cases)
    apiTypeToTableNameMap.put(Task.class, "ACT_RU_TASK");
    apiTypeToTableNameMap.put(Execution.class, "ACT_RU_EXECUTION");
    apiTypeToTableNameMap.put(ProcessInstance.class, "ACT_RU_EXECUTION");
    apiTypeToTableNameMap.put(ProcessDefinition.class, "ACT_RE_PROCDEF");
    apiTypeToTableNameMap.put(Deployment.class, "ACT_RE_DEPLOYMENT");
    apiTypeToTableNameMap.put(Job.class, "ACT_RU_JOB");
    apiTypeToTableNameMap.put(Model.class, "ACT_RE_MODEL");

    // history
    apiTypeToTableNameMap.put(HistoricProcessInstance.class, "ACT_HI_PROCINST");
    apiTypeToTableNameMap.put(HistoricActivityInstance.class, "ACT_HI_ACTINST");
    apiTypeToTableNameMap.put(HistoricDetail.class, "ACT_HI_DETAIL");
    apiTypeToTableNameMap.put(HistoricVariableUpdate.class, "ACT_HI_DETAIL");
    apiTypeToTableNameMap.put(HistoricFormProperty.class, "ACT_HI_DETAIL");
    apiTypeToTableNameMap.put(HistoricTaskInstance.class, "ACT_HI_TASKINST");
    apiTypeToTableNameMap.put(HistoricVariableInstance.class, "ACT_HI_VARINST");

    // identity
    apiTypeToTableNameMap.put(Group.class, "ACT_ID_GROUP");
    apiTypeToTableNameMap.put(User.class, "ACT_ID_USER");

    // TODO: Identity skipped for the moment as no SQL injection is provided
    // here
  }

以Task接口为例

可以看到接口的实现类对应xml的命名空间

2.activiti表格及对应的数据

官方文档中的说明

Activiti的数据库名称都以ACT_开头。第二部分是表用例的两个字符的标识。该用例也将与服务API大致匹配。

ACT_RE_ *：RE代表repository。具有此前缀的表包含静态信息，例如流程定义和流程资源（图像，规则等）。

ACT_RU_ *：RU代表runtime。这些是运行时表，其中包含流程实例，用户任务，变量，作业等的运行时数据。Activiti仅在流程实例执行期间存储运行时数据，并在流程实例结束时删除记录。这样可以使运行时表较小而又快速。

ACT_ID_ *：ID代表identity。这些表包含身份信息，例如用户，组等。

ACT_HI_ *：HI代表history。这些表包含历史数据，例如过去的流程实例，变量，任务等。

ACT_GE_ *：general数据，用于各种用例中

初次使用中使用到的表格（后续继续补充）

类型	表格名称	存储的数据	备注
生成	ACT_GE_BYTEARRAY	存储部署的bpmn相关文件
re	ACT_RE_DEPLOYMENT	发布的流程数据
re	act_re_procdef	存储流程分解数据
runtime	ACT_RU_TASK	正在运行的任务
runtime	ACT_RU_VARIABLE	用于存储流程流转中的字段	PROC_INST_ID_ 对应ACT_RU_TASK中的EXECUTION_ID_ TASK_ID_ 对应 ACT_RU_TASK中的ID_
runtime	ACT_RU_EXECUTION	运行时流程执行实例
history	act_hi_taskinst	流程历史步骤数据
history	act_hi_variable	历史步骤流程中转字段
history	act_hi_procinst	已经发起的流程实例	已经结束的流程任务END_ACT_ID_不为空