Hibernate 注释

ase */ ME.deleteEmployee(empID2); /* List down new list of the employees */ ME.listEmployees(); } /* Method to CREATE an employee in the database */ public Integer addEmployee(String fname, String lname, int salary){ Session session = factory.openSession(); Transaction tx = null; Integer employeeID = null; try{ tx = session.beginTransaction(); Employee employee = new Employee(); employee.setFirstName(fname); employee.setLastName(lname); employee.setSalary(salary); employeeID = (Integer) session.save(employee); tx.commit(); }catch (HibernateException e) { if (tx!=null) tx.rollback(); e.printStackTrace(); }finally { session.close(); } return employeeID; } /* Method to READ all the employees */ public void listEmployees( ){ Session session = factory.openSession(); Transaction tx = null; try{ tx = session.beginTransaction(); List employees = session.createQuery("FROM Employee").list(); for (Iterator iterator = employees.iterator(); iterator.hasNext();){ Employee employee = (Employee) iterator.next(); System.out.print("First Name: " + employee.getFirstName()); System.out.print(" Last Name: " + employee.getLastName()); System.out.println(" Salary: " + employee.getSalary()); } tx.commit(); }catch (HibernateException e) { if (tx!=null) tx.rollback(); e.printStackTrace(); }finally { session.close(); } } /* Method to UPDATE salary for an employee */ public void updateEmployee(Integer EmployeeID, int salary ){ Session session = factory.openSession(); Transaction tx = null; try{ tx = session.beginTransaction(); Employee employee = (Employee)session.get(Employee.class, EmployeeID); employee.setSalary( salary ); session.update(employee); tx.commit(); }catch (HibernateException e) { if (tx!=null) tx.rollback(); e.printStackTrace(); }finally { session.close(); } } /* Method to DELETE an employee from the records */ public void deleteEmployee(Integer EmployeeID){ Session session = factory.openSession(); Transaction tx = null; try{ tx = session.beginTransaction(); Employee employee = (Employee)session.get(Employee.class, EmployeeID); session.delete(employee); tx.commit(); }catch (HibernateException e) { if (tx!=null) tx.rollback(); e.printStackTrace(); }finally { session.close(); } }}数据库配置现在，让我们创建 hibernate.cfg.xml 配置文件来定义数据库相关参数。<?xml version="1.0" encoding="utf-8"?><!DOCTYPE hibernate-configuration SYSTEM "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd"><hibernate-configuration> <session-factory> <property name="hibernate.dialect"> org.hibernate.dialect.MySQLDialect </property> <property name="hibernate.connection.driver_class"> com.mysql.jdbc.Driver </property> <!-- Assume students is the database name --> <property name="hibernate.connection.url"> jdbc:mysql://localhost/test </property> <property name="hibernate.connection.username"> root </property> <property name="hibernate.connection.password"> cohondob </property></session-factory></hibernate-configuration>编译和执行这里是编译并运行以上提到的应用程序的步骤。再继续编译和运行之前需要确保你正确设置路径和类路径。从目录中删除 Employee.hbm.xml 映射文件。创建上述 Employee.java 源文件并编译。创建上述 ManageEmployee.java 源文件并编译。执行 ManageEmployee 二进制程序。你将得到如下结果，并且会在 EMPLOYEE 表中记录。$java ManageEmployee.......VARIOUS LOG MESSAGES WILL DISPLAY HERE........First Name: Zara Last Name: Ali Salary: 1000First Name: Daisy Last Name: Das Salary: 5000First Name: John Last Name: Paul Salary: 10000First Name: Zara Last Name: Ali Salary: 5000First Name: John Last Name: Paul Salary: 10000如果你查看 EMPLOYEE 表，它将有如下记录：mysql> select * from EMPLOYEE;+----+------------+-----------+--------+| id | first_name | last_name | salary |+----+------------+-----------+--------+| 29 | Zara | Ali | 5000 || 31 | John | Paul | 10000 |+----+------------+-----------+--------+2 rows in set (0.00 secmysql>