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实体类

package pers.zhang.entity;/** * @author zhang * @date 2019/12/15 - 22:10 */import javax.persistence.*;import java.util.HashSet;import java.util.Set;/** *  1.实体类和表的映射关系 *      @Entity *      @Table *  2.类中属性和表中字段的映射关系 *      @Id *      @GeneratedValue *      @Colum */@Entity //声明实体类@Table(name="cst_customer") //建立实体类和表的映射关系public class Customer {
       @Id//声明当前私有属性为主键    @GeneratedValue(strategy= GenerationType.IDENTITY) //配置主键的生成策略    @Column(name="cust_id") //指定和表中cust_id字段的映射关系    private Long custId;    @Column(name="cust_name") //指定和表中cust_name字段的映射关系    private String custName;    @Column(name="cust_source")//指定和表中cust_source字段的映射关系    private String custSource;    @Column(name="cust_industry")//指定和表中cust_industry字段的映射关系    private String custIndustry;    @Column(name="cust_level")//指定和表中cust_level字段的映射关系    private String custLevel;    @Column(name="cust_address")//指定和表中cust_address字段的映射关系    private String custAddress;    @Column(name="cust_phone")//指定和表中cust_phone字段的映射关系    private String custPhone;    //配置客户和联系人之间的关系（一对多）    /*        1.声明关系：            配置一对多关系：@OneToMany：targetEntity（对方对象的字节码）        2.配置外键（中间表）            name:外键字段的名称            referencedColumnName：参照的主表的主键字段名称        在客户实体类上（一的一方）添加了外键的配置，所以对于客户而言，也具备了维护外键的作用        实际情况下，只需要一方维护关系即可            mappedBy表示：放弃外键维护，由对方维护，取值为对方配置关系的属性名称        级联：cascade            CascadeType.ALL:所有                        MERGE:更新                        PERSIST：保存                        REMOVE：删除     *///    @OneToMany(targetEntity = LinkMan.class)//    @JoinColumn(name = "lkm_cust_id", referencedColumnName = "cust_id")    @OneToMany(mappedBy = "customer", cascade = CascadeType.ALL)    private Set
   
     linkMans = new HashSet<>();    public Set
    
      getLinkMans() {
           return linkMans;    }    public void setLinkMans(Set
     
       linkMans) {
           this.linkMans = linkMans;    }    public Long getCustId() {
           return custId;    }    public void setCustId(Long custId) {
           this.custId = custId;    }    public String getCustName() {
           return custName;    }    public void setCustName(String custName) {
           this.custName = custName;    }    public String getCustSource() {
           return custSource;    }    public void setCustSource(String custSource) {
           this.custSource = custSource;    }    public String getCustIndustry() {
           return custIndustry;    }    public void setCustIndustry(String custIndustry) {
           this.custIndustry = custIndustry;    }    public String getCustLevel() {
           return custLevel;    }    public void setCustLevel(String custLevel) {
           this.custLevel = custLevel;    }    public String getCustAddress() {
           return custAddress;    }    public void setCustAddress(String custAddress) {
           this.custAddress = custAddress;    }    public String getCustPhone() {
           return custPhone;    }    public void setCustPhone(String custPhone) {
           this.custPhone = custPhone;    }    @Override    public String toString() {
           return "Customer{" +                "custId=" + custId +                ", custName='" + custName + '\'' +                ", custSource='" + custSource + '\'' +                ", custIndustry='" + custIndustry + '\'' +                ", custLevel='" + custLevel + '\'' +                ", custAddress='" + custAddress + '\'' +                ", custPhone='" + custPhone + '\'' +                '}';    }}
     
    
   

package pers.zhang.entity;import org.springframework.test.context.ContextConfiguration;import sun.awt.SunHints;import javax.naming.Name;import javax.persistence.*;/** * @author zhang * @date 2019/12/17 - 20:23 */@Entity@Table(name = "cst_linkman")public class LinkMan {
       @Id    @GeneratedValue(strategy = GenerationType.IDENTITY)    @Column(name = "lkm_id")    private Long lkmId;//联系人编号    @Column(name = "lkm_name")    private String lkmName;//联系人姓名    @Column(name = "lkm_gender")    private String lkmGender;//联系人性别    @Column(name = "lkm_phone")    private String lkmPhone;//联系人办公电话    @Column(name = "lkm_mobile")    private String lkmMobile;//联系人手机    @Column(name = "lkm_email")    private String lkmEmail;//联系人E-mail    @Column(name = "lkm_position")    private String lkmPosition;//联系人地址    @Column(name = "lkm_memo")    private String lkmMemo;//联系人备注    //配置联系人到客户的多对一关系    /*        @ManyToOne：配置多对一关系            targetEntity：对方的实体类额字节码        @JoinColumn：配置外键（中间表）            name:外键字段名            referencedColumnName：外键引用的主表主键字段名     */    @ManyToOne(targetEntity = Customer.class)    @JoinColumn(name = "lkm_cust_id", referencedColumnName = "cust_id")    private Customer customer;    public Customer getCustomer() {
           return customer;    }    public void setCustomer(Customer customer) {
           this.customer = customer;    }    public Long getLkmId() {
           return lkmId;    }    public void setLkmId(Long lkmId) {
           this.lkmId = lkmId;    }    public String getLkmName() {
           return lkmName;    }    public void setLkmName(String lkmName) {
           this.lkmName = lkmName;    }    public String getLkmGender() {
           return lkmGender;    }    public void setLkmGender(String lkmGender) {
           this.lkmGender = lkmGender;    }    public String getLkmPhone() {
           return lkmPhone;    }    public void setLkmPhone(String lkmPhone) {
           this.lkmPhone = lkmPhone;    }    public String getLkmMobile() {
           return lkmMobile;    }    public void setLkmMobile(String lkmMobile) {
           this.lkmMobile = lkmMobile;    }    public String getLkmEmail() {
           return lkmEmail;    }    public void setLkmEmail(String lkmEmail) {
           this.lkmEmail = lkmEmail;    }    public String getLkmPosition() {
           return lkmPosition;    }    public void setLkmPosition(String lkmPosition) {
           this.lkmPosition = lkmPosition;    }    public String getLkmMemo() {
           return lkmMemo;    }    public void setLkmMemo(String lkmMemo) {
           this.lkmMemo = lkmMemo;    }}

Dao接口

package pers.zhang.dao;import org.springframework.data.jpa.repository.JpaRepository;import org.springframework.data.jpa.repository.JpaSpecificationExecutor;import pers.zhang.entity.Customer;/** * @author zhang * @date 2019/12/17 - 20:22 */public interface CustomerDao extends JpaRepository
   
    , JpaSpecificationExecutor
    
      {
   }
    
   

package pers.zhang.dao;import org.springframework.data.jpa.repository.JpaRepository;import org.springframework.data.jpa.repository.JpaSpecificationExecutor;import pers.zhang.entity.LinkMan;/** * @author zhang * @date 2019/12/17 - 20:36 */public interface LinkManDao extends JpaRepository
   
    , JpaSpecificationExecutor
    
      {
   }
    
   

测试类

package pers.zhang;import org.junit.Test;import org.junit.runner.RunWith;import org.springframework.beans.factory.annotation.Autowired;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;import pers.zhang.dao.CustomerDao;import pers.zhang.dao.LinkManDao;import pers.zhang.entity.Customer;import pers.zhang.entity.LinkMan;/** * @author zhang * @date 2019/12/17 - 20:23 */@RunWith(SpringJUnit4ClassRunner.class)@ContextConfiguration(locations = "classpath:applicationContext.xml")public class myTest {
       @Autowired    private CustomerDao customerDao;    @Autowired    private LinkManDao linkManDao;    /*        保存一个客户，一个联系人     */    @Test    @Transactional    @Rollback(false)    public void testAdd(){
           Customer customer = new Customer();        customer.setCustName("百度百度");        LinkMan linkMan = new LinkMan();        linkMan.setLkmName("小李");        //客户对外键进行维护        customer.getLinkMans().add(linkMan);        linkManDao.save(linkMan);        customerDao.save(customer);        /*            Hibernate: insert into cst_linkman (lkm_cust_id, lkm_email, lkm_gender, lkm_memo, lkm_mobile, lkm_name, lkm_phone, lkm_position) values (?, ?, ?, ?, ?, ?, ?, ?)            Hibernate: insert into cst_customer (cust_address, cust_industry, cust_level, cust_name, cust_phone, cust_source) values (?, ?, ?, ?, ?, ?)            Hibernate: update cst_linkman set lkm_cust_id=? where lkm_id=?         */    }    @Test    @Transactional    @Rollback(false)    public void testAdd2(){
           Customer customer = new Customer();        customer.setCustName("育碧");        LinkMan linkMan = new LinkMan();        linkMan.setLkmName("歌玲");        //联系人维护关系        linkMan.setCustomer(customer);        linkManDao.save(linkMan);        customerDao.save(customer);        /*            Hibernate: insert into cst_linkman (lkm_cust_id, lkm_email, lkm_gender, lkm_memo, lkm_mobile, lkm_name, lkm_phone, lkm_position) values (?, ?, ?, ?, ?, ?, ?, ?)            Hibernate: insert into cst_customer (cust_address, cust_industry, cust_level, cust_name, cust_phone, cust_source) values (?, ?, ?, ?, ?, ?)            Hibernate: update cst_linkman set lkm_cust_id=?, lkm_email=?, lkm_gender=?, lkm_memo=?, lkm_mobile=?, lkm_name=?, lkm_phone=?, lkm_position=? where lkm_id=?         */    }    /*        级联：操作一个对象的同时操作它的关联对象        级联操作：            1. 需要区分操作主体            2. 需要在操作主体的实体类上，添加级联属性（需要添加到多表映射关系的注解上）            3. cascade（配置级联）        级联添加：            示例：保存一个客户的同时保存联系人        级联删除：            示例：删除一个客户的同时删除对应的所有联系人     */    /*        级联添加：保存一个客户的同时保存联系人     */    @Test    @Transactional    @Rollback(false)    public void testCascadeAdd(){
           Customer customer = new Customer();        customer.setCustName("任天堂");        LinkMan linkMan1 = new LinkMan();        linkMan1.setLkmName("AAA");        LinkMan linkMan2 = new LinkMan();        linkMan2.setLkmName("BBB");        //联系人维护关系        linkMan1.setCustomer(customer);        linkMan2.setCustomer(customer);        customer.getLinkMans().add(linkMan1);        customer.getLinkMans().add(linkMan2);        customerDao.save(customer);        /*            Hibernate: insert into cst_customer (cust_address, cust_industry, cust_level, cust_name, cust_phone, cust_source) values (?, ?, ?, ?, ?, ?)            Hibernate: insert into cst_linkman (lkm_cust_id, lkm_email, lkm_gender, lkm_memo, lkm_mobile, lkm_name, lkm_phone, lkm_position) values (?, ?, ?, ?, ?, ?, ?, ?)            Hibernate: insert into cst_linkman (lkm_cust_id, lkm_email, lkm_gender, lkm_memo, lkm_mobile, lkm_name, lkm_phone, lkm_position) values (?, ?, ?, ?, ?, ?, ?, ?)         */    }    /*        删除主表数据：            1. 有从表数据：                1.1：在默认情况下，它会把外键字段置为null，然后删除主表数据。如果在数据库的表结构上，外键字段有非空约束，默认情况就会报错。                1.2：如果配置了放弃维护关联关系，则不能删除（与外键字段是否允许为null没有关系），因为在删除时，它根本不会去更新从表的外键字段。                1.3：如果还想删除，使用级联删除引用            2. 没有从表数据： 随便删~~~     */    /*        级联删除:删除客户的同时，删除对应的所有联系人     */    @Test    @Transactional    @Rollback(false)    public void testCascadeDelete(){
           Customer customer = customerDao.findOne(14L);        customerDao.delete(customer);        /*            Hibernate: select customer0_.cust_id as cust_id1_0_0_, customer0_.cust_address as cust_add2_0_0_, customer0_.cust_industry as cust_ind3_0_0_, customer0_.cust_level as cust_lev4_0_0_, customer0_.cust_name as cust_nam5_0_0_, customer0_.cust_phone as cust_pho6_0_0_, customer0_.cust_source as cust_sou7_0_0_ from cst_customer customer0_ where customer0_.cust_id=?            Hibernate: select linkmans0_.lkm_cust_id as lkm_cust9_1_0_, linkmans0_.lkm_id as lkm_id1_1_0_, linkmans0_.lkm_id as lkm_id1_1_1_, linkmans0_.lkm_cust_id as lkm_cust9_1_1_, linkmans0_.lkm_email as lkm_emai2_1_1_, linkmans0_.lkm_gender as lkm_gend3_1_1_, linkmans0_.lkm_memo as lkm_memo4_1_1_, linkmans0_.lkm_mobile as lkm_mobi5_1_1_, linkmans0_.lkm_name as lkm_name6_1_1_, linkmans0_.lkm_phone as lkm_phon7_1_1_, linkmans0_.lkm_position as lkm_posi8_1_1_ from cst_linkman linkmans0_ where linkmans0_.lkm_cust_id=?            Hibernate: delete from cst_linkman where lkm_id=?            Hibernate: delete from cst_linkman where lkm_id=?            Hibernate: delete from cst_customer where cust_id=?         */    }}

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