public JSONArray getTreeNodes(String departmentSn) { Department department = new Department(); JSONArray jsonArray = new JSONArray(); if (!departmentSn.equals("-1")) { department.setParentDepartmentSn(departmentSn); } else { //这里将department的一个布尔属性设置为true department.setHasActivated(true); } //在这里进行筛选 List departments = departmentMapper.select(department); System.out.print(departments); for (Department DEP : departments) { Department d = new Department(); Department sonDepartment = departmentMapper.selectByPrimaryKey(DEP.getDepartmentSn()); JSONObject jsonObject = new JSONObject(); jsonObject.put("label", sonDepartment.getDepartmentName()); jsonObject.put("data", sonDepartment.getDepartmentSn()); d.setParentDepartmentSn(DEP.getDepartmentSn()); if (departmentMapper.selectCount(department) == 0) { jsonObject.put("leaf", true); } else { jsonObject.put("leaf", false); } jsonArray.add(jsonObject); } return jsonArray; } }

In the above code, when I pass in a departmentSn that is not -1, it does not enter the else branch. However, after the following filtering, the result set is empty, as shown below

The size here is 0.
And when I change the boolean attribute in the entity class to a string attribute (as shown in the picture)

before fixing

After modification

The filtering results are normal.

The size here is 8.
Why is this?
In addition, I also tried to manually change the boolean The attribute is assigned to false, and the result is also empty. As shown below.