1、关于数据库:是部门和员工的关系
关于entity和xx.hbm.xml的实现
Dept.class
package cn.itcast.entity; import java.util.HashSet; import java.util.Set; public class Dept { private int deptId; private String deptName; // 【一对多】 部门对应的多个员工 private Set<Employee> emps = new HashSet<Employee>(); public Dept(int deptId, String deptName) { super(); this.deptId = deptId; this.deptName = deptName; } public Dept() { super(); } public int getDeptId() { return deptId; } public void setDeptId(int deptId) { this.deptId = deptId; } public String getDeptName() { return deptName; } public void setDeptName(String deptName) { this.deptName = deptName; } public Set<Employee> getEmps() { return emps; } public void setEmps(Set<Employee> emps) { this.emps = emps; } @Override public String toString() { return "Dept [deptId=" + deptId + ", deptName=" + deptName + "]"; } }
Dept.hbm.xml
<?xml version="1.0"?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"> <hibernate-mapping package="cn.itcast.entity"> <class name="Dept" table="t_dept" > <id name="deptId"> <generator class="native"></generator> </id> <property name="deptName" length="20"></property> <set name="emps"> <key column="dept_id"></key> <one-to-many class="Employee"/> </set> </class> </hibernate-mapping>
Employee.class
package cn.itcast.entity; public class Employee { private int empId; private String empName; private double salary; // 【多对一】员工与部门 private Dept dept;; public int getEmpId() { return empId; } public void setEmpId(int empId) { this.empId = empId; } public String getEmpName() { return empName; } public void setEmpName(String empName) { this.empName = empName; } public double getSalary() { return salary; } public void setSalary(double salary) { this.salary = salary; } public Dept getDept() { return dept; } public void setDept(Dept dept) { this.dept = dept; } }
Employee.hbm.xml
<?xml version="1.0"?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"> <hibernate-mapping package="cn.itcast.entity"> <class name="Employee" table="t_employee"> <id name="empId"> <generator class="native"></generator> </id> <property name="empName" length="20"></property> <property name="salary" type="double"></property> <many-to-one name="dept" column="dept_id" class="Dept"></many-to-one> </class> </hibernate-mapping>
2、关于dao的实现
DeptDao.java
package cn.itcast.dao; import cn.itcast.entity.Dept; import cn.itcast.utils.HibernateUtils; public class DeptDao { /** * 主键查询 */ public Dept findById(int id){ // 获取session, 执行操作 return (Dept) HibernateUtils.getSession().get(Dept.class, id); } }
3、关于serrvice的实现
DeptService.java
package cn.itcast.service; import cn.itcast.dao.DeptDao; import cn.itcast.entity.Dept; import cn.itcast.utils.HibernateUtils; public class DeptService { // 调用的dao private DeptDao deptDao = new DeptDao(); public Dept findById(int id){ return deptDao.findById(id); } }
4、关于Action的实现
DeptAction.java
package cn.itcast.action; import cn.itcast.entity.Dept; import cn.itcast.service.DeptService; import com.opensymphony.xwork2.ActionContext; import com.opensymphony.xwork2.ActionSupport; public class DeptAction extends ActionSupport{ // Service private DeptService deptService = new DeptService(); // 默认处理方法 public String execute() { // 主键查询(模拟数据) Dept dept = deptService.findById(12); // 保存 ActionContext.getContext().getContextMap().put("dept", dept); return SUCCESS; } }
4、session拦截器的实现
SessionInterceptor.java
package cn.itcast.interceptor; import org.hibernate.Session; import cn.itcast.utils.HibernateUtils; import com.opensymphony.xwork2.ActionInvocation; import com.opensymphony.xwork2.interceptor.AbstractInterceptor; /** * Session管理拦截器: * 当访问action的时候,创建session; * action ---> service --> dao 【获取的是这里创建的session】 * @author Jie.Yuan * */ public class SessionInterceptor extends AbstractInterceptor { @Override public String intercept(ActionInvocation invocation) throws Exception { try { // 1. 先创建Session Session session = HibernateUtils.getSession(); // 2. 开启事务 session.beginTransaction(); // 3. 执行Action String result = invocation.invoke(); // 4. 提交事务 session.getTransaction().commit(); // 不需要关闭session // 返回结果视图 return result; } catch (Exception e) { e.printStackTrace(); return "error"; } } }
5、关于HibernateUtils的实现
package cn.itcast.utils; import org.hibernate.Session; import org.hibernate.SessionFactory; import org.hibernate.cfg.Configuration; public class HibernateUtils { // 初始化SessionFactory private static SessionFactory sf; static { sf = new Configuration().configure().buildSessionFactory(); } // 创建(获取)Session public static Session getSession() { // 线程的方式创建session,必须要配置 // 可以不用关闭,会自动关。 return sf.getCurrentSession(); } }
6、关于hibernate.cfg.xml文件配置
<!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd"> <hibernate-configuration> <!-- 通常,一个session-factory节点代表一个数据库 --> <session-factory> <!-- 1. 数据库连接配置 --> <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property> <property name="hibernate.connection.url">jdbc:mysql:///hib_demo</property> <property name="hibernate.connection.username">root</property> <property name="hibernate.connection.password">root</property> <!-- 数据库方法配置, hibernate在运行的时候,会根据不同的方言生成符合当前数据库语法的sql --> <property name="hibernate.dialect">org.hibernate.dialect.MySQL5Dialect</property> <!-- 2. 其他相关配置 --> <!-- 2.1 显示hibernate在运行时候执行的sql语句 --> <property name="hibernate.show_sql">true</property> <!-- 2.2 格式化sql <property name="hibernate.format_sql">true</property> --> <!-- 2.3 自动建表 --> <property name="hibernate.hbm2ddl.auto">update</property> <!-- 配置session的创建方式:线程方式创建session对象 --> <property name="hibernate.current_session_context_class">thread</property> <!--****************** 【连接池配置】****************** --> <!-- 配置连接驱动管理类 --> <property name="hibernate.connection.provider_class">org.hibernate.connection.C3P0ConnectionProvider</property> <!-- 配置连接池参数信息 --> <property name="hibernate.c3p0.min_size">2</property> <property name="hibernate.c3p0.max_size">4</property> <property name="hibernate.c3p0.timeout">5000</property> <property name="hibernate.c3p0.max_statements">10</property> <property name="hibernate.c3p0.idle_test_period">30000</property> <property name="hibernate.c3p0.acquire_increment">2</property> <!--****************** 【二级缓存配置】****************** --> <!-- a. 开启二级缓存 --> <property name="hibernate.cache.use_second_level_cache">true</property> <!-- b. 指定使用哪一个缓存框架(默认提供的) --> <property name="hibernate.cache.provider_class">org.hibernate.cache.HashtableCacheProvider</property> <!-- 开启查询缓存 --> <property name="hibernate.cache.use_query_cache">true</property> <!-- c. 指定哪一些类,需要加入二级缓存 --> <class-cache usage="read-write" class="cn.itcast.b_second_cache.Dept"/> <class-cache usage="read-only" class="cn.itcast.b_second_cache.Employee"/> <!-- 集合缓存[集合缓存的元素对象,也加加入二级缓存] --> <collection-cache usage="read-write" collection="cn.itcast.b_second_cache.Dept.emps"/> <!-- 3. 加载所有映射 <mapping resource="cn/itcast/a_hello/Employee.hbm.xml"/> --> </session-factory> </hibernate-configuration> <!-- 开启查询缓存 --> <property name="hibernate.cache.use_query_cache">true</property> <!-- c. 指定哪一些类,需要加入二级缓存 --> <class-cache usage="read-write" class="com.baowei.entity.Group" /> <class-cache usage="read-only" class="com.baowei.entity.User" /> <!-- 集合缓存[集合缓存的元素对象,也加加入二级缓存] --> <collection-cache usage="read-write" collection="com.baowei.entity.Group.users" />
7、关于struts.xml文件的配置
<!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd"> <hibernate-configuration> <session-factory> <!-- 数据库连接信息 --> <property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property> <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property> <property name="hibernate.connection.url">jdbc:mysql:///hib_demo</property> <property name="hibernate.connection.username">root</property> <property name="hibernate.connection.password">root</property> <property name="hibernate.show_sql">true</property> <property name="hibernate.hbm2ddl.auto">update</property> <!-- session创建方式 --> <property name="hibernate.current_session_context_class">thread</property> <!-- 加载映射 --> <mapping resource="cn/itcast/entity/Dept.hbm.xml"/> <mapping resource="cn/itcast/entity/Employee.hbm.xml"/> </session-factory> </hibernate-configuration>
时间: 2024-10-17 08:33:30