Erste Schritte mit MyBatis (2) --- eins-zu-eins, eins-zu-viele

1. Erstellen Sie eine Datenbanktabelle

1.1. Erstellen Sie eine Datentabelle und fügen Sie gleichzeitig Daten ein

/*SQLyog EnterPRise v12.09 (64 Bit )MySQL - 5.6.27 -log : Datenbank - 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_MO DE, 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 'Primärschlüssel der Autor-ID',
`author_username` varchar(30) NOT NULL COMMENT 'Autor-Benutzername',
`author_passWord` varchar(32) NOT NULL COMMENT 'Author-Passwort' ,
`author_email` varchar(50) NOT NULL COMMENT 'E-Mail des Autors',
`author_bio` varchar(1000) DEFAULT 'Dieser Typ ist sehr schlecht, er hat nichts hinterlassen' KOMMENTAR 'Über den Autor',
`register_time` datetime DEFAULT CURRENT_TIMESTAMP COMMENT 'Registrierungszeit' , PRIMARY KEY (`author_id`)
) ENGINE=InnoDB AUTO_INCREMENT=6 DEFAULT CHARSET=utf8;/*Daten für die Tabelle `author` */

in `author`(` author_id`,`author_username`,`author_password`,`author_email`,`author_bio`,`register_time`) Werte einfügen (1,'Zhang San','123456', '123@QQ.com','Zhang San ist ein Neuling, habe gerade mit der Registrierung begonnen','2015-10-29 10:23:59'),(2,'李思','123asf','lisi@ 163.com','hunmiannying','2015-10-29 10 :24:29'),(3,'Wang Wu','dfsd342','ww@sina.com','Kangxi Dynasty','2015 -10-29 10:25:23'),(4,' Zhao Liu','123098sdfa','zhaoliu@qq.com','Hua Wu Gu','2015-10-29 10:26:09' ),(5,'Qian Qi','zxasqw','qianqi @qq.com','Dieser Typ ist sehr faul und hat nichts hinterlassen','2015-10-29 10:27:04'),(6, 'Zhang Sanfeng','123456','zhangsf@qq.com ','Dieser Typ ist ein Drecksack und hat nichts zurückgelassen','2015-10-29 11:48:00'),(7,'Zhang Wuji' ,'qwertyuiop','wuji@163.com','Dieser Typ ist sehr schlecht und hat nichts zurückgelassen','2015-10-29 11:48:24');

/*Tabellenstruktur für Tabelle „Blog“ */DROP TABLE IF EXISTS „Blog“;CREATE TABLE „Blog“ (
„Blog_ID“ int(11) unsigned NOT NULL AUTO_INCREMENT COMMENT „BlogId-Primärschlüssel“,
`blog_title` varchar(255) NOT NULL COMMENT 'Blog Title',
`author_id` int(11) unsigned NOT NULL COMMENT 'author ID Foreign Key', 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;/*Daten für die Tabelle `blog` * /insert into `blog`(`blog_id`,`blog_title`,`author_id`) Werte (1,'Xiao Zhangs Blog',1),(2,'Xiao Li',2),(3,'王五Kein Mensch',3),(4,'Zhao Diren',4),(5,'Qian Qian Qian',5);/*Tabellenstruktur für Tabelle „Beiträge“ */DROP TABLE IF EXISTS ` posts`; CREATE TABLE `posts` (
`post_id` int(11) unsigned NOT NULL AUTO_INCREMENT COMMENT 'Post-Primärschlüssel-ID',
`post_subject` varchar(255) NOT NULL COMMENT 'Post-Betreff, Titel' ,
`post_body` text NOT NULL COMMENT 'Beitragsinhalt kann bis zu 3000 Zeichen lang sein',
`blog_id` int(11) unsigned NOT NULL COMMENT 'Blog-Primärschlüssel als Fremdschlüssel',
`createtime ` datetime DEFAULT CURRENT_TIMESTAMP COMMENT 'Zeitpunkt der Artikelerstellung', 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;/*Daten für die Tabelle „posts“ */insert into „posts“(`post_id`,`post_subject`,`post_body`,`blog_id`,`createtime` ) Werte (1,'Mybatis Erste Schritte 1','Was ist MyBatis? rnMyBatis ist ein hervorragendes Persistenzschicht-Framework, das benutzerdefiniertes SQL, gespeicherte Prozeduren und erweiterte Zuordnung unterstützt. MyBatis vermeidet fast den gesamten JDBC-Code und das manuelle Festlegen von Parametern sowie das Abrufen von Ergebnismengen. MyBatis kann einfaches XML oder Annotationen für die Konfiguration und native Maps verwenden, um Schnittstellen und Java-POJOs (Plain Old Java Objects, gewöhnliche Java-Objekte) Datensätzen in der Datenbank zuzuordnen. ',1,'2015-10-29 10:32:21'),(2,'Erste Schritte mit Mybatis 2','Um MyBatis zu verwenden, platzieren Sie einfach die Datei mybatis-x.x.x.jar im Klassenpfad.',1 , '2015-10-29 10:32:52'),(3,'Oracle Learning','Oracle Database, auch bekannt als Oracle RDBMS oder kurz Oracle. Es ist ein relationales Datenbankverwaltungssystem der Oracle Company',2 , '2015-10-29 10:33:26'),(4,'JAVA Learning 1','Java ist der allgemeine Name der objektorientierten Programmiersprache Java und der Java-Plattform, die im Mai 1995 von Sun Microsystems eingeführt wurde', 3,'2015-10-29 10:34:17'),(5,'PL/SQL','PL/SQL ist auch eine Programmiersprache namens Procedural Language/SQL. PL/SQL Es ist eine Erweiterung der Oracle-Datenbank zu SQL-Anweisungen', 4, '2015-10-29 10:37:52'), (6, 'CSS-Tag-Selektor', 'Tag-Selektor rnID-Selektor rn Klassen-Selektor rn spezielle Auswahl ',5,'2015-10- 29 10:39:44'),(7,'javascript','js: ist eine Front-End-Skriptsprache',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 */;

2. Erstellen Sie das Projekt

2.1. Erstellen Sie das Projekt und fügen Sie das JAR-Paket hinzu

2.2. Entitätsklasse am Beispiel des Autors erstellen

package com.pb.mybatis.po;import java.util.Date;/**
*

* @Title: Author.java

* @Package com.pb.mybatis.po

* @ClassName Author

* @Beschreibung: TODO (Blog-Autorenklasse)

* @Autor Liu Nan

* @Datum 29.10.2015 9:27:53 Uhr

* @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 die Autoren-ID    */
   public int getAuthorId() {        return authorId;
   }    /**
    * @param authorId die festzulegende Autoren-ID    */
   public void setAuthorId(int authorId) {        this.authorId = authorId;    }    /**
    * @return the authorUserName    */
   public String getAuthorEmail() {        return authorEmail;
   }    /**
    * @param AuthorUserName der festzulegende AuthorUserName    */
   public void setAuthorEmail(String authorEmail ) {        this.authorEmail = authorEmail;
   }    /**
    * @return theauthorPassword    */
   public int getAuthorBio() {        return authorBio;
   }    /**
    * @param AuthorPassword das festzulegende AuthorPassword    */
   public void io (int authorBio) {        this.authorBio = authorBio;
   }    /**
    * @return the authorEmail    */
   public Date getRegisterTime() {        return registerTime;
   }    /**
    * @param authorE-Mail an den festzulegenden AutorE-Mail    */
public void setRegisterTime(Date registerTime) {        this.registerTime = registerTime;
   }    /**
    * @return the authorBio    */
   @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

Konfiguration
 PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-config.dtd">
   < ;transactionManager type="JDBC"/>
   
       

       
       
    SELECT * FROM author
WHERE author_id=#{authorId} SELECT * FROM author
WHERE author_username LIKE "% "#{ name}"%"INSERT INTO author(author_username,author_password,author_email, author_bio,register_time)
VALUES(#{authorUserName},#{authorPassword},#{authorEmail},#{authorBio},#{registerTime}) update author
set
author_username=#{authorUserName},
author_password=#{authorPassword},
author_email=#{authorEmail} ,
author_bio =#{authorBio},
register_time=#{registerTime}
where author_id=#{authorId}< ;delete id="deleteAuthor " parameterType="int">delete from author
where author_id=#{authorId}

3 des Hinzufügens, Löschens, Änderns und Suchens

3.1 Die Testklasse nimmt den Autor als Beispiel

/***/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 (Testen)

* @Autor Liu Nan

* @Datum 29.10.2015 11:57:21

* @Version V1.0

*/public class AuthorMapperTest {    
   private SqlSessionFactory sqlSessionFactory;    
   /**
*
* @Title: setUp

* @Description: TODO (Methode wird vor jeder Methode ausgeführt)

* @throws Exception void*/
   @Before    public void setUp() throws Exception {
       String resources="configuration.xml";
       InputStream in=Resources.getResourceAsStream(resource);        //获取会话工厂
       sqlSessionFactory=new SqlSessionFactoryBuilder().build(in);
   }    /**
*
* @Title: testFindAuthorById

* @Description: TODO (Benutzer basierend darauf finden)
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();
   }    /**
*
* @Title: testFindAuthorByName

* @Description: TODO (Fuzzy-Abfrage basierend auf Benutzername)
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
               Liste Authors=authorMapper.findAuthorByName("张");
               System.out.println(authors);                //关闭会话                sqlSession.close();                for(Author a:authors){
                   System.out.println(a.toString());
               {        //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.setAuthor E-Mail("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(); sqlSession.close();
} /**
*
* @Title: testUpdateAuthor

* @Description: TODO (Benutzer ändern)
void*/
@Test public void testUpdateAuthor() { //Sitzung abrufen
SqlSession sqlSession=sqlSessionFactory.openSession() ; );
author.setAuthor Bio("Hahahahayahoo");
             author.setRegisterTime(new Date());               int num=authorMapper.updateAuthor(author); System.out.println= .getAuthorId()); 🎜> } /**
*
* @Title: testDeleteAuthor

* @Description: TODO (Autor basierend auf ID löschen)
void*/
@Test public void testDeleteAuthor() {               //Get session
                  sqlSession=sqlSessionFactory.openSession();                         ); //Methode aufrufen
> int num=authorMapper.deleteAuthor(10);
System.out.println("num="+num);

sqlSession.commit(); //Sitzung schließen sqlSession.close ();
}

}




Vier. Eins-zu-eins implementieren

4.1 . Blog-Klasse gründen

package com.pb.mybatis.po;/**

* @Title: Blog.java

* @Package com.pb.mybatis.po

* @ClassName Blog

* @Description: TODO (Blog)

* @Autor Liu Nan

* @Datum 29.10.2015 9:32:56

* @Version V1.0

*/public class Blog {    //博客ID
   private int blogId;    
   //标题
   private String blogTitle;    
   //博客作者
   privater Autor Autor;    /**
    * @return die blogId    */
   public int getBlogId() {        return blogId;
   }    /**
    * @param blogId die festzulegende blogId    */
   public void setBlogId(int blogId) {        this.blogId = blogId;
   }    /**
    * @return the blogTitle    */
   public String getBlogTitle() {        return blogTitle;
   }    /**
    * @param blogTitle der festzulegende blogTitle    */
   public void setBlogTitle(String blogTitle) {        this.blogTitle = blogTitle;
   }    /**
    * @return den Autor    */
   public Author getAuthor() {        return author;
   }    /**
    * @param author der festzulegende Autor    */
   public void setAuthor(Author author) {        this .author = author;
   }    /**(nicht Javadoc)
   
    *

Titel: toString

   
    *

Beschreibung: 重写toString方法

   
* @return
   
    * @see java.lang.Object#toString()    */
   @Override    public String toString() {        return "Blog [blogId=" + blogId + ", blogTitle=" + blogTitle                + ", author= " + Autor + "]";
   }
   
   
}

 

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 (Beschreiben Sie in einem Satz, was diese Datei bewirkt)

* @author Liu Nan

* @date 29.10.2015 11:13:21

* @version V1.0

*/public interface BlogMapper {    /**
*
* @Title: findBlogById

* @Description: TODO (BLOG basierend auf ID finden)

* @param id
* @return Blog*/
   public Blog findBlogById(int id);    
   /**
*
* @Title: findByName

* @Description: TODO(nach Blog-Namen suchen)

* @param name
* @return List*/
   öffentliche Liste findBlogByName(String blogTitle);    
   /**
*
* @Title: addBlog

* @Description: TODO(Blog hinzufügen)

* @param blog
* @return int*/
   public int addBlog(Blog blog);    
   
   /**
*
* @Title: updateBlog

* @Description: TODO (Blog ändern)

* @param blog
* @return int*/
   public int updateBlog(Blog blog);    
   /**
*
* @Title: deleteBlog

* @Description: TODO(Blog löschen)

* @param id
* @return int*/
   public int deleteBlog(int id);
}

 

4.3、建立mapper.xml

 

br/> PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd"> < ;!-- Die zweite Methode
ordnet die Autorenklasse in einer resultMap


Gemeinsame Attribute entsprechen Feldern in der Tabelle






--> 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
WO blog.author_id=author.author_id
UND blog.blog_id=#{blogId} 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
VON blog,author
WO blog.author_id=author.author_id
UND blog_title LIKE "%"#{blogTitle}"%"< ;/select>INSERT INTO blog(blog_title,author_id)
VALUES(#{blogTitle} ,#{author.authorId})Blog AKTUALISIEREN
SET blog_title=#{blogTitle} ,
author_id=#{author.authorId}
WHERE blog_id=#{blogId}aus Blog löschen, wobei blog_id=#{blogId}

4.1, Testklasse

Paket 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 (Beschreiben Sie in einem Satz, was diese Datei bewirkt)

* @author Liu Nan

* @date 29.10.2015 15:12:52

* @version V1.0

*/public class BlogMapperTest {    private SqlSessionFactory sqlSessionFactory;

   
   @Before    public void setUp() löst eine Ausnahme aus {
       String resources="configuration.xml";
       InputStream in=Resources.getResourceAsStream(resource);        //获取会话工厂
       sqlSessionFactory=new SqlSessionFactoryBuilder().build(in);
   }    /**
    * Testmethode für {@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();
   }    /**
    * Testmethode für {@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 blogs=blogMapper.findBlogByName("小");
       System.out.println(blogs);        //关闭会话        sqlSession();
   }    /**
    * Testmethode für {@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. begehen( );
               sqlSession.close();
   }    /**
    * Testmethode für {@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();
   }    /**
    * Testmethode für {@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Beiträge类

 

package com.pb.mybatis.po;import java.util.Date;/**

* @Title: Posts.java

* @Package com.pb.mybatis.po

* @ClassName Posts

* @Description: TODO (Blog-Artikel)

* @author Liu Nan

* @date 29.10.2015 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 die festzulegende PostId    */
   public void setPostId(int postId) {        this .postId = postId;
   }    /**
    * @return the postSubject    */
   public String getPostSubject() {        return postSubject;
   }    /**
    * @param postSubject das festzulegende postSubject    */
   public void setPostSubject(String postSubject ) {        this.postSubject = postSubject;
   }    /**
    * @return the postBody    */
   public String getPostBody() {        return postBody;
   }    /**
    * @param postBody der festzulegende PostBody    */
   public void setPostBody (String postBody) {        this.postBody = postBody;
   }   /**
    * @return the createTime    */
   public Date getCreateTime() {        return createTime;
   }    /**
    * @param createTime die festzulegende createTime    */
public void setCreateTime(Date createTime) {        this.createTime = createTime;
   }    /**(nicht Javadoc)
   
    *

Title: toString

   
    *

Description:重写toString方法

   
* @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 (Blog)

* @Autor Liu Nan

* @Datum 29.10.2015 9:32:56

* @Version V1.0

*/public class Blog {    //博客ID
   private int blogId;    
   //标题
   private String blogTitle;    
   //博客作者
   privater Autor Autor;    
   //文章List
   private Liste Beiträge;    /**
    * @return die blogId    */
   public int getBlogId() {        return blogId;
   }    /**
    * @param blogId die festzulegende blogId    */
   public void setBlogId(int blogId) {        this.blogId = blogId;
   }    /**
    * @return the blogTitle    */
   public String getBlogTitle() {        return blogTitle;
   }    /**
    * @param blogTitle der festzulegende blogTitle    */
   public void setBlogTitle(String blogTitle) {        this.blogTitle = blogTitle;
   }    /**
    * @return den Autor    */
   public Author getAuthor() {        return author;
   }    /**
    * @param author der festzulegende Autor    */
   public void setAuthor(Author author) {        this .author = author;
   }    /**
    * @return die Beiträge    */
   public List getPosts() {        return posts;
   }    /**
    * @param postet die festzulegenden Beiträge    */
   public void setPosts(List posts) {        this.posts = posts;
   }    /**(nicht Javadoc)
   
    *

Titel: toString

   
    *

Beschreibung:

   
    * @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

 

br/> PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd"> < ;!--One-to-many Association -->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
VON blog,author,posts
WO blog.author_id=author.author_id
UND blog. blog_id=posts.blog_id
AND blog .blog_id=#{blogId}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}“%“VALUES(#{blogTitle},#{author.authorId})aus Blog löschen, wobei blog_id=#{blogId}> ;

5.4, Test

Die Testklasse bleibt unverändert

Das Obige ist die Einführung in MyBatis (2) – Eins-zu-Eins-, Eins-zu-Viele-Inhalte. Für weitere verwandte Inhalte achten Sie bitte auf PHP-Chinesisch Website (www.php.cn)!