一对一关系中 从表的主键是 主表的外键
sql语句
1 create table person(
2 id int primary key,
3 name varchar(100)
4 );
5 create table idcard(
6 id int primary key,
7 num varchar(20),
8 constraint person_id_fk foreign key(id) references person(id)
9 );
View
Code
domain
Person.java
1 package cn.itcast.domain;
2
3 import java.io.Serializable;
4 /*
5 create table person(
6 id int primary key,
7 name varchar(100)
8 );
9 create table idcard(
10 id int primary key,
11 num varchar(20),
12 constraint person_id_fk foreign key(id) references person(id)
13 );
14 */
15 public class Person implements Serializable {
16 private Integer id;
17 private String name;
18 private IdCard idcard;
19 public Integer getId() {
20 return id;
21 }
22 public void setId(Integer id) {
23 this.id = id;
24 }
25 public String getName() {
26 return name;
27 }
28 public void setName(String name) {
29 this.name = name;
30 }
31 public IdCard getIdcard() {
32 return idcard;
33 }
34 public void setIdcard(IdCard idcard) {
35 this.idcard = idcard;
36 }
37
38 }
View
Code
IdCard.java
1 package cn.itcast.domain;
2
3 import java.io.Serializable;
4
5 public class IdCard implements Serializable {
6 private Integer id;
7 private String num;
8 private Person person;
9 public Integer getId() {
10 return id;
11 }
12 public void setId(Integer id) {
13 this.id = id;
14 }
15 public String getNum() {
16 return num;
17 }
18 public void setNum(String num) {
19 this.num = num;
20 }
21 public Person getPerson() {
22 return person;
23 }
24 public void setPerson(Person person) {
25 this.person = person;
26 }
27
28 }
daoImpl.java
1 package cn.itcast.dao.impl;
2
3 import java.sql.SQLException;
4
5 import org.apache.commons.dbutils.QueryRunner;
6 import org.apache.commons.dbutils.handlers.BeanHandler;
7
8 import cn.itcast.domain.IdCard;
9 import cn.itcast.domain.Person;
10 import cn.itcast.util.DBCPUtil;
11
12 public class PersonDaoImpl {
13 private QueryRunner qr = new QueryRunner(DBCPUtil.getDataSource());
14 public void addPerson(Person p) throws SQLException{
15 //保存人的基本信息
16 qr.update("insert into person (id,name) values(?,?)", p.getId(),p.getName());
17 //如果有身份证，保存身份证的基本信息
18 IdCard card = p.getIdcard();
19 if(card!=null){
20 qr.update("insert into idcard (id,num) values(?,?)", p.getId(),card.getNum());
21 }
22 }
23 //要不要查IdCard的内容。都要求查，因为Idcard是少的一方的
24 public Person findPerson(Integer id) throws SQLException{
25 Person p = qr.query("select * from person where id=?", new BeanHandler<Person>(Person.class), id);
26 if(p!=null){
27 IdCard idcard = qr.query("select * from idcard where id=?", new BeanHandler<IdCard>(IdCard.class), id);
28 p.setIdcard(idcard);
29 }
30 return p;
31 }
32 }
test测试
1 package cn.itcast.test;
2
3 import static org.junit.Assert.fail;
4
5 import java.sql.SQLException;
6
7 import org.junit.Test;
8
9 import cn.itcast.dao.impl.PersonDaoImpl;
10 import cn.itcast.domain.IdCard;
11 import cn.itcast.domain.Person;
12
13 public class PersonDaoImplTest {
14 private PersonDaoImpl dao = new PersonDaoImpl();
15 @Test
16 public void testAddPerson() throws SQLException {
17 Person p = new Person();
18 p.setId(1);
19 p.setName("zql");
20
21 IdCard idcard = new IdCard();
22 idcard.setNum("110");
23
24 p.setIdcard(idcard);
25 dao.addPerson(p);
26 }
27
28 @Test
29 public void testFindPerson() throws SQLException {
30 Person p = dao.findPerson(1);
31 System.out.println(p.getName());
32 IdCard idcard = p.getIdcard();
33 System.out.println(idcard.getNum());
34 }
35
36 }
时间： 2024-11-09 00:45:11