activiti5.14 增加新的特性

1、public interface TaskService ：

/**
   * A shortcut to {@link #claim} with null user in order to unclaim the task
   * @param taskId task to unclaim, cannot be null.
   * @throws ActivitiObjectNotFoundException when the task doesn't exist. 
   */
  void unclaim(String taskId);

怎么取消这个声明呢？activiti增加新的特性方法unclaim（）；

2、自己写sql来查询自己的任务和待办的任务

// 已经签收的或者直接分配到当前人的任务

        StringBuffer asigneeSql = new StringBuffer(" select distinct RES.* from ACT_RU_TASK RES ");
        asigneeSql.append(" inner join ACT_RE_PROCDEF D on RES.PROC_DEF_ID_ = D.ID_ ");
        asigneeSql.append(" WHERE RES.ASSIGNEE_ = #{userId}");
        asigneeSql.append(" and D.KEY_ = #{processDefinitionKey} ");
        asigneeSql.append(" and RES.SUSPENSION_STATE_ = #{suspensionState}");


        // 当前人在候选人或者候选组范围之内
        StringBuffer needClaimSql = new StringBuffer("select distinct RES1.* from ACT_RU_TASK RES1   ");
        needClaimSql.append(" inner join ACT_RU_IDENTITYLINK I on I.TASK_ID_ = RES1.ID_ ");
        needClaimSql.append(" inner join ACT_RE_PROCDEF D1 on RES1.PROC_DEF_ID_ = D1.ID_ ");
        needClaimSql.append(" WHERE D1.KEY_ = #{processDefinitionKey} ");
        needClaimSql.append(" and RES1.ASSIGNEE_ is null  ");
        needClaimSql.append(" and I.TYPE_ = 'candidate' ");
        needClaimSql.append(" and ( I.USER_ID_ = #{userId} or ");
        needClaimSql.append("  I.GROUP_ID_ IN (select g.GROUP_ID_ from ACT_ID_MEMBERSHIP g where g.USER_ID_ = #{userId} ) ) ");
        needClaimSql.append(" and RES1.SUSPENSION_STATE_ = #{suspensionState} ");