Countersigning

First of all, we need to implement a listener. There are two kinds of task listener and process listener. Here I use task listener.

public class MyTaksListener implements TaskListener {
    @Override
    public void notify(DelegateTask delegateTask) {
        System.out.println("delegateTask.getEventName() = " + delegateTask.getEventName());

        //Adding signers, all of them are approved before they can enter the next stage.

        List<String> assigneeList = new ArrayList<String>();
        assigneeList.add("lfs");
        assigneeList.add("cwb");
        delegateTask.setVariable("publicityList",assigneeList);
    }
}

Start the listener at the initiating application node in the process

Setting variables at nodes that require approval by multiple people

Use your own user table

Delete the tables act_id_user, act_id_group, act_id_membership that come with Activiti
Use views to query your own user table data instead of existing tables

DROP VIEW  IF EXISTS OYDGHR.act_id_membership;
DROP VIEW  IF EXISTS OYDGHR.act_id_user;
DROP VIEW  IF EXISTS OYDGHR.act_id_group;
-- (ID_,REV_,FIRST_,LAST_,EMAIL_,PWD_,PICTURE_ID_ ,CONSTRAINT id_pk PRIMARY KEY(ID_) RELY DISABLE NOVALIDATE)
CREATE  VIEW OYDGHR.act_id_user AS
  SELECT
    TO_CHAR(au.S01_ID) AS ID_,
    0          AS REV_,
    to_char(au.S0109)   AS FIRST_,
    '' AS LAST_,
    to_char(au.S0117)      AS EMAIL_,
    to_char(au.S0170)   AS PWD_,
    ''          AS PICTURE_ID_
  FROM OYDGHR.S01 au;

CREATE VIEW OYDGHR.act_id_group
AS
  SELECT ar.S05_ID AS ID_,
         NULL AS REV_,
         ar.S0504 AS NAME_,
         'assignment' AS TYPE_
  FROM OYDGHR.S05 ar;

CREATE VIEW OYDGHR.act_id_membership
AS
   SELECT (SELECT u.S01_ID FROM OYDGHR.S01 u WHERE u.S01_ID=ur.S01_ID) AS USER_ID_,
       (SELECT r.S05_ID FROM OYDGHR.S05 r WHERE r.S05_ID=ur.S05_ID) AS GROUP_ID_
   FROM OYDGHR.S011 ur;