jpa建表多对多

pom.xml: <?xml version="1.0" encoding="UTF-8"?><project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 　　　　　　http://maven.apache.org/xsd/maven-4.0.0.xsd"> 　　 <modelVersion>4.0.0</modelVersion> <groupId>cn.dy</groupId> <artifactId>springJpaManyToMany</artifactId> <version>1.0-SNAPSHOT</version> <properties> <spring.version>4.2.4.RELEASE</spring.version> <hibernate.version>5.0.7.Final</hibernate.version> <slf4j.version>1.6.6</slf4j.version> <log4j.version>1.2.12</log4j.version> <c3p0.version>0.9.1.2</c3p0.version> <mysql.version>5.1.6</mysql.version> <maven.compiler.source>1.8</maven.compiler.source> <maven.compiler.target>1.8</maven.compiler.target> </properties> <dependencies> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.12</version> <scope>test</scope> </dependency> <!--spring start--> <!--spring aop--> <dependency> <groupId>org.aspectj</groupId> <artifactId>aspectjweaver</artifactId> <version>1.6.8</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-aop</artifactId> <version>${spring.version}</version> </dependency> <!--spring aop--> <!--spring ioc--> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context-support</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-beans</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-core</artifactId> <version>${spring.version}</version> </dependency> <!--spring ioc--> <!--spring end--> <!--spring 对orm框架的支持包--> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-orm</artifactId> <version>${spring.version}</version> </dependency> <!--spring 对orm框架的支持包--> <!--hibernate start--> <!--hibernate 核心包--> <dependency> <groupId>org.hibernate</groupId> <artifactId>hibernate-core</artifactId> <version>${hibernate.version}</version> </dependency> <!--hibernate 对JPA实现的包--> <dependency> <groupId>org.hibernate</groupId> <artifactId>hibernate-entitymanager</artifactId> <version>${hibernate.version}</version> </dependency> <!--hibernate 验证包--> <dependency> <groupId>org.hibernate</groupId> <artifactId>hibernate-validator</artifactId> <version>5.2.1.Final</version> </dependency> <!--hibernate end--> <dependency> <groupId>c3p0</groupId> <artifactId>c3p0</artifactId> <version>${c3p0.version}</version> </dependency> <dependency> <groupId>log4j</groupId> <artifactId>log4j</artifactId> <version>${log4j.version}</version> </dependency> <dependency> <groupId>org.slf4j</groupId> <artifactId>slf4j-api</artifactId> <version>${slf4j.version}</version> </dependency> <dependency> <groupId>org.slf4j</groupId> <artifactId>slf4j-log4j12</artifactId> <version>${slf4j.version}</version> </dependency> <!--mysql的驱动包--> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>${mysql.version}</version> </dependency> <!--spring dataJpa 的坐标--> <dependency> <groupId>org.springframework.data</groupId> <artifactId>spring-data-jpa</artifactId> <version>1.9.0.RELEASE</version> </dependency> <!--spring 测试 的坐标--> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-test</artifactId> <version>${spring.version}</version> </dependency> <!-- el 标签 的坐标--> <dependency> <groupId>javax.el</groupId> <artifactId>javax.el-api</artifactId> <version>2.2.4</version> </dependency> <dependency> <groupId>org.glassfish.web</groupId> <artifactId>javax.el</artifactId> <version>2.2.4</version> </dependency> <!-- el 标签 的坐标--> </dependencies></project> resources:　　applicationContext.xml:<?xml version="1.0" encoding="UTF-8"?><beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop" xmlns:context="http://www.springframework.org/schema/context" xmlns:jdbc="http://www.springframework.org/schema/jdbc" xmlns:tx="http://www.springframework.org/schema/tx" xmlns:jpa="http://www.springframework.org/schema/data/jpa" xsi:schemaLocation=" http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd http://www.springframework.org/schema/data/jpa http://www.springframework.org/schema/data/jpa/spring-jpa.xsd"> <!--1 创建数据库的连接池--> <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource"> <property name="password" value="root"/> <property name="user" value="root"/> <property name="jdbcUrl" value="jdbc:mysql://localhost:3306/spring_data?characterEncoding=utf-8"/> <property name="driverClass" value="com.mysql.jdbc.Driver"/> </bean> <!--2 工厂类对象--> <bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean"> <!--数据源--> <property name="dataSource" ref="dataSource"/> <!--实体类的扫描器--> <property name="packagesToScan" value="cn.dy.jpa.entity"/> <!--jpa配置供应商的适配器--> <property name="jpaVendorAdapter"> <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter"> <!-- 指定数据库类型--> <property name="database" value="MYSQL"/> <!-- 是否自动创建数据库表--> <property name="generateDdl" value="true"/> <!-- 数据库方言 支持的特有语法--> <property name="databasePlatform" value="org.hibernate.dialect.MySQLDialect"/> <!--是否向控制台输出语句 update hibernate.hbm2ddl.auto--> <property name="showSql" value="true"/> </bean> </property> <property name="jpaProperties"> <props> <prop key="hibernate.hbm2ddl.auto">update</prop> </props> </property> </bean> <!--配置事物--> <bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager"> <property name="entityManagerFactory" ref="entityManagerFactory"/> </bean> <!--一般出现在sevice层 start--> <tx:advice id="txAdvice" transaction-manager="transactionManager"> <tx:attributes> <tx:method name="save*" propagation="REQUIRED"/> <tx:method name="insert*" propagation="REQUIRED"/> <tx:method name="update*" propagation="REQUIRED"/> <tx:method name="delete*" propagation="REQUIRED"/> <tx:method name="get*" read-only="true"/> <tx:method name="find*" read-only="true"/> <tx:method name="*" propagation="REQUIRED"/> </tx:attributes> </tx:advice> <!--aop--> <aop:config> <aop:pointcut id="pointcut" expression="execution(* cn.dy.jpa.service.*.*(..))"/> <aop:advisor advice-ref="txAdvice" pointcut-ref="pointcut"/> </aop:config> <!--一般出现在sevice层 end--><!-- <context:component-scanspring base-package="cn.dy.jpa"></context:component-scan>--><!-- spring dataJpa 整合 dao--> <jpa:repositories base-package="cn.dy.jpa.dao" transaction-manager-ref="transactionManager" entity-manager-factory-ref="entityManagerFactory"/></beans>entity:　　SysUser主表： package cn.dy.jpa.entity;import javax.persistence.*;import java.io.Serializable;import java.util.HashSet;import java.util.Set;/** * author:dingyi * time:2019/8/21 0021 10:02 */@Entity@Table(name = "sys_user")public class SysUser implements Serializable { @GeneratedValue(strategy = GenerationType.IDENTITY) @Id @Column(name="user_id") private long userId; @Column(name="username") private String username; @Column(name="password") private String password; /** * 配置用户到角色的多对多关系 * 配置多对多的映射关系 * 1.声明表关系的配置 * @ManyToMany(targetEntity = SysRole.class,cascade = CascadeType.ALL) //多对多 * targetEntity：代表对方的实体类字节码 * 2.配置中间表（包含两个外键） * @JoinTable * name : 中间表的名称 * joinColumns：配置当前对象在中间表的外键 * @JoinColumn的数组 * name：外键名 * referencedColumnName：参照的主表的主键名 * inverseJoinColumns：配置对方对象在中间表的外键 */ @ManyToMany(targetEntity = SysRole.class,cascade = CascadeType.ALL) @JoinTable(name = "sys_user_role", // joinColumns 当前表在中间表中的外键 参照当前表的主键字段 joinColumns = {@JoinColumn(name = "userid", referencedColumnName = "user_id")}, // inverseJoinColumns 对方对象在中间表 的外键 参照当前表的主键字段 inverseJoinColumns = {@JoinColumn( name = "roleid", referencedColumnName = "role_id")} ) private Set<SysRole> roles = new HashSet<>(); public long getUserId() { return userId; } public void setUserId(long userId) { this.userId = userId; } public String getUsername() { return username; } public void setUsername(String username) { this.username = username; } public String getPassword() { return password; } public void setPassword(String password) { this.password = password; } public Set<SysRole> getRoles() { return roles; } public void setRoles(Set<SysRole> roles) { this.roles = roles; } @Override public String toString() { return "SysUser{" + "userId=" + userId + ", username='" + username + '\'' + ", password='" + password + '\'' + '}'; }} SysRole从表： package cn.dy.jpa.entity;import javax.persistence.*;import java.io.Serializable;import java.util.HashSet;import java.util.Set;/** * author:dingyi * time:2019/8/21 0021 10:02 */@Entity@Table(name = "sys_role")public class SysRole implements Serializable { @Id @GeneratedValue(strategy = GenerationType.IDENTITY) @Column(name="role_id") private long roleId; @Column(name="role_name") private String rolename; @Column(name="memo") private String memo; @ManyToMany(mappedBy = "roles",fetch = FetchType.LAZY)//放弃维护权 private Set<SysUser> users = new HashSet<>(); @Override public String toString() { return "SysRole{" + "roleId=" + roleId + ", rolename='" + rolename + '\'' + ", memo='" + memo + '\'' + '}'; } public long getRoleId() { return roleId; } public void setRoleId(long roleId) { this.roleId = roleId; } public String getRolename() { return rolename; } public void setRolename(String rolename) { this.rolename = rolename; } public String getMemo() { return memo; } public void setMemo(String memo) { this.memo = memo; } public Set<SysUser> getUsers() { return users; } public void setUsers(Set<SysUser> users) { this.users = users; }} dao层：　　userdao： package cn.dy.jpa.dao;import cn.dy.jpa.entity.SysUser;import org.springframework.data.jpa.repository.JpaRepository;import org.springframework.data.jpa.repository.JpaSpecificationExecutor;/** * author:dingyi * time:2019/8/21 0021 10:03 */public interface SysUserDao extends JpaRepository<SysUser,Long>, JpaSpecificationExecutor<SysUser> {} roledao: package cn.dy.jpa.dao;import cn.dy.jpa.entity.SysRole;import org.springframework.data.jpa.repository.JpaRepository;import org.springframework.data.jpa.repository.JpaSpecificationExecutor;/** * author:dingyi * time:2019/8/21 0021 10:04 */public interface SysRoleDao extends JpaRepository<SysRole,Long>, JpaSpecificationExecutor<SysRole> {} test类： import cn.dy.jpa.dao.SysRoleDao;import cn.dy.jpa.dao.SysUserDao;import cn.dy.jpa.entity.SysRole;import cn.dy.jpa.entity.SysUser;import org.junit.Test;import org.junit.runner.RunWith;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.test.annotation.Commit;import org.springframework.test.annotation.Rollback;import org.springframework.test.context.ContextConfiguration;import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;import org.springframework.transaction.annotation.Transactional;/** * author:dingyi * time:2019/8/21 0021 11:52 */@RunWith(SpringJUnit4ClassRunner.class)@ContextConfiguration("classpath:applicationContext.xml")public class testManyToMany { @Autowired SysUserDao userDao; @Autowired SysRoleDao roleDao; @Test @Transactional @Commit public void addUserAndRole(){ // 1创建用户 SysUser sysUser = new SysUser(); sysUser.setUsername("admin"); sysUser.setPassword("123456"); // 2创建 角色 SysRole sysRole = new SysRole(); sysRole.setRolename("管理员"); sysRole.setMemo("权限"); // 3 配置用户和角色之间的关系 sysUser.getRoles().add(sysRole); sysRole.getUsers().add(sysUser); //4 把用户角色写入数据可 userDao.save(sysUser); //roleDao.save(sysRole); //无需再写 } @Test @Transactional @Commit public void addUserAndRole1(){ // 1创建用户 SysUser user = new SysUser(); user.setUsername("林志玲"); user.setPassword("123456"); SysUser user1 = new SysUser(); user1.setUsername("杨幂"); user1.setPassword("123456"); // 2创建 角色 SysRole role = new SysRole(); role.setRolename("演员"); SysRole rol = new SysRole(); rol.setRolename("女主脚"); // 3 配置用户和角色之间的关系 user.getRoles().add(role); user.getRoles().add(rol); user1.getRoles().add(rol); user1.getRoles().add(role); role.getUsers().add(user); role.getUsers().add(user1); rol.getUsers().add(user); rol.getUsers().add(user1); //4 把用户角色写入数据可 userDao.save(user); userDao.save(user1); } /** * 删除操作 * 在多对多的删除时，双向级联删除根本不能配置 * 禁用 * 如果配了的话，如果数据之间有相互引用关系，可能会清空所有数据 */ @Test @Transactional @Commit @Rollback(false) public void removeUserAndRole(){ userDao.delete(1L); userDao.delete(2L); }}

转载于:https://www.cnblogs.com/dingyi-boss/p/11439580.html