POJO(plain ordinary java object)
contain only data attribute and getter/setter functions
example:
public class User {
private long id;
private String name;
public void setId(long id) {
this. id = id;
}
public void setName(String name) {
this. name=name;
}
public long getId() {
return id;
}
}
DAO(data access object)
contain code to connect POJO class object and database
example:
package test;
public class UserTableDAO extends BaseDAO implements IUserTableDAO {
public UserTable validateUser(String username, String password) {
//查询userTable表中的记录
String hql = "from UserTableu where u.username=? and u.pasword=?";
Session session = getSession();
Query query = session.createQuery(hql);
query.setParameter(0, username);
query.setParameter(1, password);
List users = query.list();
Iterator it = users.iterator();
while (it.hasNext()) {
if (users.size() != 0) {
UserTable user = (UserTable) it.next();
return user;
}
}
session.close();
return null;
}
}
Service class
built based on DAO object to handle business logic
example:
package test;
public class StudentServiceManage implements StudentServicel {
//对XSDao和jDao进行依赖注入
private StudentDao studentDao;
private RecordDao recordDao;
/*业务实现:学生信息查询*/
public List findAl(int pageNow, int pageSize) {//显示所有学生信息
return studentDao.findAl(pageNow, pageSize);
}
public int findStudentSizeOK() {//查询一共有多少条学生记录
return studentDao.findStudentSize();
}
/*业务实现:查看某个学生的详细信息*/
public Student find(String sid) {//根据学号查询某学生信息
return studentDao.find(sid);
}
/*业务实现:删除某学生信息*/
public void delete(String sid) {//根据学号删除学生
recordDao.deleteOnestudentRecord(sid);
studentDao.delete(sid);
}
}