一、创建数据库表
1.1、创建数据表同时插入数据
/*
SQLyog Enterprise v12.09 (64 bit)
MySQL - 5.6.27-log : Database - mybatis
*********************************************************************
*/ /*!40101 SET NAMES utf8 */; /*!40101 SET SQL_MODE=''*/; /*!40014 SET @OLD_UNIQUE_CHECKS=@@UNIQUE_CHECKS, UNIQUE_CHECKS=0 */;
/*!40014 SET @OLD_FOREIGN_KEY_CHECKS=@@FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0 */;
/*!40101 SET @OLD_SQL_MODE=@@SQL_MODE, SQL_MODE='NO_AUTO_VALUE_ON_ZERO' */;
/*!40111 SET @OLD_SQL_NOTES=@@SQL_NOTES, SQL_NOTES=0 */;
CREATE DATABASE /*!32312 IF NOT EXISTS*/`mybatis` /*!40100 DEFAULT CHARACTER SET utf8 */; USE `mybatis`; /*Table structure for table `author` */ DROP TABLE IF EXISTS `author`; CREATE TABLE `author` (
`author_id` int(11) unsigned NOT NULL AUTO_INCREMENT COMMENT '作者ID主键',
`author_username` varchar(30) NOT NULL COMMENT '作者用户名',
`author_password` varchar(32) NOT NULL COMMENT '作者密码',
`author_email` varchar(50) NOT NULL COMMENT '作者邮箱',
`author_bio` varchar(1000) DEFAULT '这家伙很赖，什么也没留下' COMMENT '作者简介',
`register_time` datetime DEFAULT CURRENT_TIMESTAMP COMMENT '注册时间',
PRIMARY KEY (`author_id`)
) ENGINE=InnoDB AUTO_INCREMENT=6 DEFAULT CHARSET=utf8; /*Data for the table `author` */
insert into `author`(`author_id`,`author_username`,`author_password`,`author_email`,`author_bio`,`register_time`) values (1,'张三','123456','123@qq.com','张三是个新手，刚开始注册','2015-10-29 10:23:59'),(2,'李四','123asf','lisi@163.com','魂牵梦萦 ','2015-10-29 10:24:29'),(3,'王五','dfsd342','ww@sina.com','康熙王朝','2015-10-29 10:25:23'),(4,'赵六','123098sdfa','zhaoliu@qq.com','花午骨','2015-10-29 10:26:09'),(5,'钱七','zxasqw','qianqi@qq.com','这家伙很赖，什么也没留下','2015-10-29 10:27:04'),(6,'张三丰','123456','zhangsf@qq.com','这家伙很赖，什么也没留下','2015-10-29 11:48:00'),(7,'张无忌','qwertyuiop','wuji@163.com','这家伙很赖，什么也没留下','2015-10-29 11:48:24');
/*Table structure for table `blog` */ DROP TABLE IF EXISTS `blog`; CREATE TABLE `blog` (
`blog_id` int(11) unsigned NOT NULL AUTO_INCREMENT COMMENT 'BlogId主键',
`blog_title` varchar(255) NOT NULL COMMENT 'blog标题',
`author_id` int(11) unsigned NOT NULL COMMENT '作者ID外键',
PRIMARY KEY (`blog_id`),
KEY `fk_author_id` (`author_id`),
CONSTRAINT `fk_author_id` FOREIGN KEY (`author_id`) REFERENCES `author` (`author_id`)
) ENGINE=InnoDB AUTO_INCREMENT=6 DEFAULT CHARSET=utf8; /*Data for the table `blog` */ insert into `blog`(`blog_id`,`blog_title`,`author_id`) values (1,'小张的Blog',1),(2,'小李',2),(3,'王五不是人',3),(4,'赵地人',4),(5,'钱钱钱',5); /*Table structure for table `posts` */ DROP TABLE IF EXISTS `posts`; CREATE TABLE `posts` (
`post_id` int(11) unsigned NOT NULL AUTO_INCREMENT COMMENT '文章主键ID',
`post_subject` varchar(255) NOT NULL COMMENT '文章主题，标题',
`post_body` text NOT NULL COMMENT '文章内容最大3000个字符',
`blog_id` int(11) unsigned NOT NULL COMMENT 'Blog主键做外键',
`createtime` datetime DEFAULT CURRENT_TIMESTAMP COMMENT '文章创建时间',
PRIMARY KEY (`post_id`),
KEY `fk_blog_id` (`blog_id`),
CONSTRAINT `fk_blog_id` FOREIGN KEY (`blog_id`) REFERENCES `blog` (`blog_id`)
) ENGINE=InnoDB AUTO_INCREMENT=8 DEFAULT CHARSET=utf8mb4; /*Data for the table `posts` */ insert into `posts`(`post_id`,`post_subject`,`post_body`,`blog_id`,`createtime`) values (1,'Mybatis入门一','什么是 MyBatis ？\r\nMyBatis 是支持定制化 SQL、存储过程以及高级映射的优秀的持久层框架。MyBatis 避免了几乎所有的 JDBC 代码和手动设置参数以及获取结果集。MyBatis 可以对配置和原生Map使用简单的 XML 或注解，将接口和 Java 的 POJOs(Plain Old Java Objects,普通的 Java对象)映射成数据库中的记录。',1,'2015-10-29 10:32:21'),(2,'Mybatis入门二','要使用 MyBatis， 只需将 mybatis-x.x.x.jar 文件置于 classpath 中即可。',1,'2015-10-29 10:32:52'),(3,'Oracle学习','Oracle Database，又名Oracle RDBMS，或简称Oracle。是甲骨文公司的一款关系数据库管理系统',2,'2015-10-29 10:33:26'),(4,'JAVA学习一','Java是由Sun Microsystems公司于1995年5月推出的Java面向对象程序设计语言和Java平台的总称',3,'2015-10-29 10:34:17'),(5,'PL/SQL','PL/SQL也是一种程序语言，叫做过程化SQL语言（Procedural Language/SQL）。PL/SQL是Oracle数据库对SQL语句的扩展',4,'2015-10-29 10:37:52'),(6,'CSS标签选择器','标签选择器\r\nID选择器\r\n类选择器\r\n特殊选择器',5,'2015-10-29 10:39:44'),(7,'javascript','js:是前端脚本语言',2,'2015-10-29 10:40:18'); /*!40101 SET SQL_MODE=@OLD_SQL_MODE */;
/*!40014 SET FOREIGN_KEY_CHECKS=@OLD_FOREIGN_KEY_CHECKS */;
/*!40014 SET UNIQUE_CHECKS=@OLD_UNIQUE_CHECKS */;
/*!40111 SET SQL_NOTES=@OLD_SQL_NOTES */;
二、创建项目
2.1、创建项目并加入jar包
2.2、创建实体类以author为例
package com.pb.mybatis.po; import java.util.Date; /**
* * @Title: Author.java * @Package com.pb.mybatis.po * @ClassName Author * @Description: TODO(Blog作者类) * @author 刘楠 * @date 2015-10-29 上午9:27:53 * @version V1.0
*/
public class Author {
//作者ID
private int authorId; //作者用户名
private String authorUserName; //作者密码
private String authorPassword; //作者邮箱
private String authorEmail; //作者介绍
private int authorBio; //注册时间
private Date registerTime; /**
* @return the authorId
*/
public int getAuthorId() {
return authorId;
} /**
* @param authorId the authorId to set
*/
public void setAuthorId(int authorId) {
this.authorId = authorId;
} /**
* @return the authorUserName
*/
public String getAuthorUserName() {
return authorUserName;
} /**
* @param authorUserName the authorUserName to set
*/
public void setAuthorUserName(String authorUserName) {
this.authorUserName = authorUserName;
} /**
* @return the authorPassword
*/
public String getAuthorPassword() {
return authorPassword;
} /**
* @param authorPassword the authorPassword to set
*/
public void setAuthorPassword(String authorPassword) {
this.authorPassword = authorPassword;
} /**
* @return the authorEmail
*/
public String getAuthorEmail() {
return authorEmail;
} /**
* @param authorEmail the authorEmail to set
*/
public void setAuthorEmail(String authorEmail) {
this.authorEmail = authorEmail;
} /**
* @return the authorBio
*/
public int getAuthorBio() {
return authorBio;
} /**
* @param authorBio the authorBio to set
*/
public void setAuthorBio(int authorBio) {
this.authorBio = authorBio;
} /**
* @return the registerTime
*/
public Date getRegisterTime() {
return registerTime;
} /**
* @param registerTime the registerTime to set
*/
public void setRegisterTime(Date registerTime) {
this.registerTime = registerTime;
} /** (non Javadoc) * <p>Title: toString</p> * <p>Description:重写toString方法 </p> * @return * @see java.lang.Object#toString()
*/
@Override
public String toString() {
return "Author [authorId=" + authorId + ", authorUserName="
+ authorUserName + ", authorPassword=" + authorPassword
+ ", authorEmail=" + authorEmail + ", authorBio=" + authorBio
+ ", registerTime=" + registerTime + "]";
} }
2.3、创建mybatis配置文件
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE configuration
PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-config.dtd"> <configuration>
<properties resource="db.properties" />
<typeAliases>
<!--使用默认别名 -->
<package name="com.pb.mybatis.po"/>
</typeAliases>
<environments default="development">
<environment id="development">
<transactionManager type="JDBC"/>
<dataSource type="POOLED">
<property name="driver" value="${jdbc.driver}"/>
<property name="url" value="${jdbc.url}"/>
<property name="username" value="${jdbc.username}"/>
<property name="password" value="${jdbc.password}"/>
</dataSource>
</environment>
</environments>
<mappers>
<!-- 加载映射 --> <package name="com.pb.mybatis.mapper"/>
</mappers>
</configuration>
2.4、创建实体类对象的接口以author为例
/**
*/
package com.pb.mybatis.mapper; import java.util.List; import com.pb.mybatis.po.Author; /** * @Title: AuthorMapper.java * @Package com.pb.mybatis.mapper * @ClassName AuthorMapper * @Description: TODO(作者接口) * @author 刘楠 * @date 2015-10-29 上午11:13:10 * @version V1.0 */
public interface AuthorMapper { /**
*
* @Title: findById * @Description: TODO(根据查找一个用户) * @param id
* @return Author
*/
public Author findAuthorById(int authorId); /**
*
* @Title: findByName * @Description: TODO(根据用户名，模糊查询) * @param name
* @return List<Author>
*/
public List<Author> findAuthorByName(String name); /**
*
* @Title: addAuthor * @Description: TODO(添加作者) * @param author
* @return int
*/
public int addAuthor(Author author); /**
*
* @Title: updateAuthor * @Description: TODO(修改用户) * @param authro
* @return int
*/
public int updateAuthor(Author authro); /**
*
* @Title: deleteAturho * @Description: TODO(根据ID删除作者) * @param id
* @return int
*/
public int deleteAuthor(int authorId); }
2.5、创建接口对应的mapper.xm以author为例
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.pb.mybatis.mapper.AuthorMapper">
<!--使用resultMap映射 type使用别名，-->
<resultMap type="Author" id="authorResultMap">
<!--主键 -->
<id property="authorId" column="author_id"/>
<!--普通属性与表中的字段对应 -->
<result property="authorUserName" column="author_username"/>
<result property="authorPassword" column="author_password"/>
<result property="authorEmail" column="author_email"/>
<result property="authorBio" column="author_bio"/>
<result property="registerTime" column="register_time"/>
</resultMap> <!--根据查找一个用户 -->
<select id="findAuthorById" parameterType="int" resultMap="authorResultMap">
SELECT * FROM author
WHERE author_id=#{authorId}
</select> <!-- 根据用户名，模糊查询 --> <select id="findAuthorByName" parameterType="String" resultMap="authorResultMap">
SELECT * FROM author
WHERE author_username LIKE "%"#{name}"%"
</select> <!--添加用户
useGeneratedKeys="true" 使用数据库自增序列 keyProperty="authorId"将主键返回
#号中写PO类中的属性
-->
<insert id="addAuthor" parameterType="Author" useGeneratedKeys="true" keyProperty="authorId">
INSERT INTO author(author_username,author_password,author_email,author_bio,register_time)
VALUES(#{authorUserName},#{authorPassword},#{authorEmail},#{authorBio},#{registerTime})
</insert>
<!--修改用户 -->
<update id="updateAuthor" parameterType="Author">
update author
set
author_username=#{authorUserName},
author_password=#{authorPassword},
author_email=#{authorEmail},
author_bio=#{authorBio},
register_time=#{registerTime}
where author_id=#{authorId}
</update>
<!--删除用户 根据ID-->
<delete id="deleteAuthor" parameterType="int">
delete from author
where author_id=#{authorId}
</delete>
</mapper>
三、简单实现增删改查
3.1、测试类以author为例
/**
*/
package com.pb.mybatis.mapper;
import java.io.InputStream;
import java.util.Date;
import java.util.List; import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.junit.Before;
import org.junit.Test; import com.pb.mybatis.po.Author; /** * @Title: AuthorMapperTest.java * @Package com.pb.mybatis.mapper * @ClassName AuthorMapperTest * @Description: TODO(测试) * @author 刘楠 * @date 2015-10-29 上午11:57:21 * @version V1.0 */
public class AuthorMapperTest { private SqlSessionFactory sqlSessionFactory; /**
*
* @Title: setUp * @Description: TODO(在每个方法前执行的方法) * @throws Exception void
*/
@Before
public void setUp() throws Exception {
String resource="configuration.xml";
InputStream in=Resources.getResourceAsStream(resource);
//获取会话工厂
sqlSessionFactory=new SqlSessionFactoryBuilder().build(in);
} /**
*
* @Title: testFindAuthorById * @Description: TODO(根据查找一个用户)
void
*/
@Test
public void testFindAuthorById() {
//获取会话
SqlSession sqlSession=sqlSessionFactory.openSession();
//Mapper接口
AuthorMapper authorMapper=sqlSession.getMapper(AuthorMapper.class);
//调用方法
Author author=authorMapper.findAuthorById(2);
System.out.println(author);
//关闭会话
sqlSession.close();
} /**
*
* @Title: testFindAuthorByName * @Description: TODO(根据用户名，模糊查询)
void
*/
@Test
public void testFindAuthorByName() {
//获取会话
SqlSession sqlSession=sqlSessionFactory.openSession();
//Mapper接口
AuthorMapper authorMapper=sqlSession.getMapper(AuthorMapper.class);
//调用方法
List<Author> authors=authorMapper.findAuthorByName("张");
System.out.println(authors);
//关闭会话
sqlSession.close();
for(Author a:authors){
System.out.println(a.toString());
}
} /**
*
* @Title: testAddAuthor * @Description: TODO(添加作者)
void
*/
@Test
public void testAddAuthor() {
//获取会话
SqlSession sqlSession=sqlSessionFactory.openSession();
//Mapper接口
AuthorMapper authorMapper=sqlSession.getMapper(AuthorMapper.class);
//调用方法
Author author=new Author();
author.setAuthorUserName("不知道");
author.setAuthorPassword("1234567890");
author.setAuthorEmail("123456@qq.com");
author.setAuthorBio("知道是个什么");
author.setRegisterTime(new Date());
int num=authorMapper.addAuthor(author);
System.out.println("num="+num);
System.out.println("authorId="+author.getAuthorId());
sqlSession.commit();
//关闭会话
sqlSession.close(); } /**
*
* @Title: testUpdateAuthor * @Description: TODO(修改用户)
void
*/
@Test
public void testUpdateAuthor() {
//获取会话
SqlSession sqlSession=sqlSessionFactory.openSession();
//Mapper接口
AuthorMapper authorMapper=sqlSession.getMapper(AuthorMapper.class);
//调用方法
Author author=authorMapper.findAuthorById(8);
author.setAuthorUserName("知道了");
author.setAuthorPassword("456789");
author.setAuthorEmail("456789@qq.com");
author.setAuthorBio("哈哈哈哈哈雅虎");
author.setRegisterTime(new Date());
int num=authorMapper.updateAuthor(author);
System.out.println("num="+num);
System.out.println("authorId="+author.getAuthorId());
sqlSession.commit();
//关闭会话
sqlSession.close(); } /**
*
* @Title: testDeleteAuthor * @Description: TODO(根据ID删除作者)
void
*/
@Test
public void testDeleteAuthor() {
//获取会话
SqlSession sqlSession=sqlSessionFactory.openSession();
//Mapper接口
AuthorMapper authorMapper=sqlSession.getMapper(AuthorMapper.class);
//调用方法 int num=authorMapper.deleteAuthor(10);
System.out.println("num="+num); sqlSession.commit();
//关闭会话
sqlSession.close();
} }
四、实现一对一
4.1、建立Blog类
package com.pb.mybatis.po; /** * @Title: Blog.java * @Package com.pb.mybatis.po * @ClassName Blog * @Description: TODO(博客) * @author 刘楠 * @date 2015-10-29 上午9:32:56 * @version V1.0 */
public class Blog { //博客ID
private int blogId; //标题
private String blogTitle; //博客作者
private Author author; /**
* @return the blogId
*/
public int getBlogId() {
return blogId;
} /**
* @param blogId the blogId to set
*/
public void setBlogId(int blogId) {
this.blogId = blogId;
} /**
* @return the blogTitle
*/
public String getBlogTitle() {
return blogTitle;
} /**
* @param blogTitle the blogTitle to set
*/
public void setBlogTitle(String blogTitle) {
this.blogTitle = blogTitle;
} /**
* @return the author
*/
public Author getAuthor() {
return author;
} /**
* @param author the author to set
*/
public void setAuthor(Author author) {
this.author = author;
} /** (non Javadoc) * <p>Title: toString</p> * <p>Description: 重写toString方法</p> * @return * @see java.lang.Object#toString()
*/
@Override
public String toString() {
return "Blog [blogId=" + blogId + ", blogTitle=" + blogTitle
+ ", author=" + author + "]";
} }
4.2、建立BlogMapper接口
/**
*/
package com.pb.mybatis.mapper; import java.util.List; import com.pb.mybatis.po.Author;
import com.pb.mybatis.po.Blog; /** * @Title: BlogMapper.java * @Package com.pb.mybatis.mapper * @ClassName BlogMapper * @Description: TODO(用一句话描述该文件做什么) * @author 刘楠 * @date 2015-10-29 上午11:13:21 * @version V1.0 */
public interface BlogMapper { /**
*
* @Title: findBlogById * @Description: TODO(根据ID查找BLOG) * @param id
* @return Blog
*/
public Blog findBlogById(int id); /**
*
* @Title: findByName * @Description: TODO(根据博客名查找) * @param name
* @return List<Blog>
*/
public List<Blog> findBlogByName(String blogTitle); /**
*
* @Title: addBlog * @Description: TODO(添加博客) * @param blog
* @return int
*/
public int addBlog(Blog blog); /**
*
* @Title: updateBlog * @Description: TODO(修改博客) * @param blog
* @return int
*/
public int updateBlog(Blog blog); /**
*
* @Title: deleteBlog * @Description: TODO(删除博客) * @param id
* @return int
*/
public int deleteBlog(int id);
}
4.3、建立mapper.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.pb.mybatis.mapper.BlogMapper">
<!--使用ResultMap -->
<resultMap type="Blog" id="blogResultMap">
<!--主键 -->
<id property="blogId" column="blog_id"/>
<!--标题 -->
<result property="blogTitle" column="blog_title"/>
<!--一对一关联 第一种-->
<association property="author" resultMap="authorResultMap"/> <!-- 第二种
把作者类再映射在一个resultMap中
<association property="author" resultMap="authorResultMap">
<id property="authorId" column="author_id"/>
普通属性与表中的字段对应
<result property="authorUserName" column="author_username"/>
<result property="authorPassword" column="author_password"/>
<result property="authorEmail" column="author_email"/>
<result property="authorBio" column="author_bio"/>
<result property="registerTime" column="register_time"/>
</association>
-->
</resultMap> <!--使用resultMap映射 type使用别名，单独使用Author关联-->
<resultMap type="Author" id="authorResultMap">
<!--主键 -->
<id property="authorId" column="author_id"/>
<!--普通属性与表中的字段对应 -->
<result property="authorUserName" column="author_username"/>
<result property="authorPassword" column="author_password"/>
<result property="authorEmail" column="author_email"/>
<result property="authorBio" column="author_bio"/>
<result property="registerTime" column="register_time"/>
</resultMap>
<!-- 根据ID查询-->
<select id="findBlogById" parameterType="int" resultMap="blogResultMap">
SELECT blog.blog_id,blog.blog_title,author.author_id,author.author_username,author.author_password,author.author_email,author.author_bio,author.register_time
FROM blog,author
WHERE blog.author_id=author.author_id
AND blog.blog_id=#{blogId}
</select>
<!-- 根据名字查询 -->
<select id="findBlogByName" parameterType="String" resultMap="blogResultMap">
SELECT blog.blog_id,blog.blog_title,author.author_id,author.author_username,author.author_password,author.author_email,author.author_bio,author.register_time
FROM blog,author
WHERE blog.author_id=author.author_id
AND blog_title LIKE "%"#{blogTitle}"%"
</select>
<!-- 添加Blog -->
<insert id="addBlog" parameterType="Blog" useGeneratedKeys="true" keyProperty="blogId">
INSERT INTO blog(blog_title,author_id)
VALUES(#{blogTitle},#{author.authorId})
</insert>
<!--修改 -->
<update id="updateBlog" parameterType="Blog">
UPDATE blog
SET blog_title=#{blogTitle},
author_id=#{author.authorId}
WHERE blog_id=#{blogId}
</update>
<!--删除 -->
<delete id="deleteBlog" parameterType="int">
delete from blog where blog_id=#{blogId}
</delete> </mapper>
4.1、测试类
package com.pb.mybatis.mapper; import static org.junit.Assert.*; import java.io.InputStream;
import java.util.List; import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.junit.Before;
import org.junit.Test; import com.pb.mybatis.po.Author;
import com.pb.mybatis.po.Blog; /** * @Title: BlogMapperTest.java * @Package com.pb.mybatis.mapper * @ClassName BlogMapperTest * @Description: TODO(用一句话描述该文件做什么) * @author 刘楠 * @date 2015-10-29 下午3:12:52 * @version V1.0 */
public class BlogMapperTest {
private SqlSessionFactory sqlSessionFactory; @Before
public void setUp() throws Exception {
String resource="configuration.xml";
InputStream in=Resources.getResourceAsStream(resource);
//获取会话工厂
sqlSessionFactory=new SqlSessionFactoryBuilder().build(in);
} /**
* Test method for {@link com.pb.mybatis.mapper.BlogMapper#findBlogById(int)}.
*/
@Test
public void testFindBlogById() {
//获取会话
SqlSession sqlSession=sqlSessionFactory.openSession();
//Mapper接口
BlogMapper blogMapper=sqlSession.getMapper(BlogMapper.class);
//调用方法
Blog blog=blogMapper.findBlogById(2);
System.out.println(blog);
//关闭会话
sqlSession.close();
} /**
* Test method for {@link com.pb.mybatis.mapper.BlogMapper#findBlogByName(java.lang.String)}.
*/
@Test
public void testFindBlogByName() {
//获取会话
SqlSession sqlSession=sqlSessionFactory.openSession();
//Mapper接口
BlogMapper blogMapper=sqlSession.getMapper(BlogMapper.class);
//调用方法
List<Blog> blogs=blogMapper.findBlogByName("小");
System.out.println(blogs);
//关闭会话
sqlSession.close();
} /**
* Test method for {@link com.pb.mybatis.mapper.BlogMapper#addBlog(com.pb.mybatis.po.Blog)}.
*/
@Test
public void testAddBlog() {
//获取会话
SqlSession sqlSession=sqlSessionFactory.openSession();
//Mapper接口
BlogMapper blogMapper=sqlSession.getMapper(BlogMapper.class);
Blog blog=new Blog();
blog.setBlogTitle("倚天屠龙记");
AuthorMapper authorMapper=sqlSession.getMapper(AuthorMapper.class);
//调用方法
Author author=authorMapper.findAuthorById(2);
blog.setAuthor(author);
int num=blogMapper.addBlog(blog);
System.out.println("num="+num);
System.out.println(blog.getBlogId());
sqlSession.commit();
sqlSession.close();
} /**
* Test method for {@link com.pb.mybatis.mapper.BlogMapper#updateBlog(com.pb.mybatis.po.Blog)}.
*/
@Test
public void testUpdateBlog() {
//获取会话
SqlSession sqlSession=sqlSessionFactory.openSession();
//Mapper接口
BlogMapper blogMapper=sqlSession.getMapper(BlogMapper.class);
//调用方法
Blog blog=blogMapper.findBlogById(8);
blog.setBlogTitle("笑傲江湖");
Author author=blog.getAuthor();
author.setAuthorUserName("金庸");
AuthorMapper authorMapper=sqlSession.getMapper(AuthorMapper.class);
int authorNum=authorMapper.updateAuthor(author);
int num=blogMapper.updateBlog(blog);
System.out.println("authorNum="+authorNum);
System.out.println("num="+num);
sqlSession.commit();
//关闭会话
sqlSession.close();
} /**
* Test method for {@link com.pb.mybatis.mapper.BlogMapper#deleteBlog(int)}.
*/
@Test
public void testDeleteBlog() {
//获取会话
SqlSession sqlSession=sqlSessionFactory.openSession();
//Mapper接口
BlogMapper blogMapper=sqlSession.getMapper(BlogMapper.class);
int num=blogMapper.deleteBlog(11);
System.out.println("num="+num);
sqlSession.commit();
sqlSession.close();
} }
五、一对多
5.1、建立Posts类
package com.pb.mybatis.po; import java.util.Date; /** * @Title: Posts.java * @Package com.pb.mybatis.po * @ClassName Posts * @Description: TODO(Blog文章) * @author 刘楠 * @date 2015-10-29 上午9:31:22 * @version V1.0 */
public class Posts { //文章ID
private int postId; //文件主题
private String postSubject; //主体内容
private String postBody;
//文章建立时间
private Date createTime; /**
* @return the postId
*/
public int getPostId() {
return postId;
} /**
* @param postId the postId to set
*/
public void setPostId(int postId) {
this.postId = postId;
} /**
* @return the postSubject
*/
public String getPostSubject() {
return postSubject;
} /**
* @param postSubject the postSubject to set
*/
public void setPostSubject(String postSubject) {
this.postSubject = postSubject;
} /**
* @return the postBody
*/
public String getPostBody() {
return postBody;
} /**
* @param postBody the postBody to set
*/
public void setPostBody(String postBody) {
this.postBody = postBody;
} /**
* @return the createTime
*/
public Date getCreateTime() {
return createTime;
} /**
* @param createTime the createTime to set
*/
public void setCreateTime(Date createTime) {
this.createTime = createTime;
} /** (non Javadoc) * <p>Title: toString</p> * <p>Description:重写toString方法</p> * @return * @see java.lang.Object#toString()
*/
@Override
public String toString() {
return "Posts [postId=" + postId + ", postSubject=" + postSubject
+ ", postBody=" + postBody +", createTime="
+ createTime + "]";
} }
5.2、在blog类中添加List
package com.pb.mybatis.po; import java.util.List; /** * @Title: Blog.java * @Package com.pb.mybatis.po * @ClassName Blog * @Description: TODO(博客) * @author 刘楠 * @date 2015-10-29 上午9:32:56 * @version V1.0 */
public class Blog { //博客ID
private int blogId; //标题
private String blogTitle; //博客作者
private Author author; //文章List
private List<Posts> posts; /**
* @return the blogId
*/
public int getBlogId() {
return blogId;
} /**
* @param blogId the blogId to set
*/
public void setBlogId(int blogId) {
this.blogId = blogId;
} /**
* @return the blogTitle
*/
public String getBlogTitle() {
return blogTitle;
} /**
* @param blogTitle the blogTitle to set
*/
public void setBlogTitle(String blogTitle) {
this.blogTitle = blogTitle;
} /**
* @return the author
*/
public Author getAuthor() {
return author;
} /**
* @param author the author to set
*/
public void setAuthor(Author author) {
this.author = author;
} /**
* @return the posts
*/
public List<Posts> getPosts() {
return posts;
} /**
* @param posts the posts to set
*/
public void setPosts(List<Posts> posts) {
this.posts = posts;
} /** (non Javadoc) * <p>Title: toString</p> * <p>Description: </p> * @return * @see java.lang.Object#toString()
*/
@Override
public String toString() {
return "Blog [blogId=" + blogId + ", blogTitle=" + blogTitle
+ ", author=" + author + ", posts=" + posts + "]";
} }
5.3、修改blogMapper.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.pb.mybatis.mapper.BlogMapper">
<!--使用ResultMap -->
<resultMap type="Blog" id="blogResultMap">
<!--主键 -->
<id property="blogId" column="blog_id"/>
<!--标题 -->
<result property="blogTitle" column="blog_title"/>
<!--一对一关联 第一种-->
<association property="author" resultMap="authorResultMap"/>
<!--一对多关联 -->
<collection property="posts" resultMap="postsResultMap" ofType="Posts"/> <!-- 第二种
把作者类再映射在一个resultMap中
<association property="author" resultMap="authorResultMap">
<id property="authorId" column="author_id"/>
普通属性与表中的字段对应
<result property="authorUserName" column="author_username"/>
<result property="authorPassword" column="author_password"/>
<result property="authorEmail" column="author_email"/>
<result property="authorBio" column="author_bio"/>
<result property="registerTime" column="register_time"/>
</association>
-->
</resultMap>
<!--文章Map -->
<resultMap type="Posts" id="postsResultMap">
<id property="postId" column="post_id"/>
<result property="postSubject" column="post_subject"/>
<result property="postBody" column="post_body"/>
<result property="createTime" column="createtime"/>
</resultMap>
<!--使用resultMap映射 type使用别名，单独使用Author关联-->
<resultMap type="Author" id="authorResultMap">
<!--主键 -->
<id property="authorId" column="author_id"/>
<!--普通属性与表中的字段对应 -->
<result property="authorUserName" column="author_username"/>
<result property="authorPassword" column="author_password"/>
<result property="authorEmail" column="author_email"/>
<result property="authorBio" column="author_bio"/>
<result property="registerTime" column="register_time"/>
</resultMap>
<!-- 根据ID查询-->
<select id="findBlogById" parameterType="int" resultMap="blogResultMap">
SELECT blog.blog_id,blog.blog_title,
author.author_id,author.author_username,author.author_password,author.author_email,author.author_bio,author.register_time,
posts.post_id,posts.post_subject,posts.post_body,posts.createtime,posts.blog_id
FROM blog,author,posts
WHERE blog.author_id=author.author_id
AND blog.blog_id=posts.blog_id
AND blog.blog_id=#{blogId}
</select>
<!-- 根据名字查询 -->
<select id="findBlogByName" parameterType="String" resultMap="blogResultMap">
SELECT blog.blog_id,blog.blog_title,author.author_id,author.author_username,author.author_password,author.author_email,author.author_bio,author.register_time
FROM blog,author
WHERE blog.author_id=author.author_id
AND blog_title LIKE "%"#{blogTitle}"%"
</select>
<!-- 添加Blog -->
<insert id="addBlog" parameterType="Blog" useGeneratedKeys="true" keyProperty="blogId">
INSERT INTO blog(blog_title,author_id)
VALUES(#{blogTitle},#{author.authorId})
</insert>
<!--修改 -->
<update id="updateBlog" parameterType="Blog">
UPDATE blog
SET blog_title=#{blogTitle},
author_id=#{author.authorId}
WHERE blog_id=#{blogId}
</update>
<!--删除 -->
<delete id="deleteBlog" parameterType="int">
delete from blog where blog_id=#{blogId}
</delete> </mapper>
5.4、测试
测试类不变
