------------吾亦无他,唯手熟尔，谦卑若愚，好学若饥------------- 继续上次的开始，这次记录的是增删改查，上次重复过的代码不做过多解释
首先先创建mysql的表和实体类Book
BOOK
package cn.dawn.demo01.entity;
public class Book {
private Integer bookID;
private String bookName;
private String bookAuthor;
private Integer bookPrice;
public Book() {
}
public Integer getBookID() {
return this.bookID;
}
public void setBookID(Integer bookID) {
this.bookID = bookID;
}
public String getBookName() {
return this.bookName;
}
public void setBookName(String bookName) {
this.bookName = bookName;
}
public String getBookAuthor() {
return this.bookAuthor;
}
public void setBookAuthor(String bookAuthor) {
this.bookAuthor = bookAuthor;
}
public Integer getBookPrice() {
return this.bookPrice;
}
public void setBookPrice(Integer bookPrice) {
this.bookPrice = bookPrice;
}
} 接下来是接口，我写到一块了，一次全部拿出来，我会标清除注释，给解释一下
package cn.dawn.demo01.dao;
import cn.dawn.demo01.entity.Book;
import java.util.List;
/**
* Created by Dawn on 2018/1/29.
*/
public interface IBookDAO {
//查全部
public List<Book> findAllBook();
//添加
public int insertBook(Book book);
//删除
public int deleteBook(int id);
//修改
public int updateBook(Book book);
//查都单独
public Book findOneBookByPK(int id);
} 增删改得到的返回值都是受影响的行数，查全部返回List泛型，查单独根据bookid进行查，返回的是单个对象Book
接下来是dao层同名的xml中
<?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="cn.dawn.demo01.dao.IBookDAO">
<select id="findAllBook" resultType="Book">
select * from book
</select>
<insert id="insertBook">
INSERT INTO book(bookname,bookauthor,bookprice) VALUES (#{bookName},#{bookAuthor},#{bookPrice})
</insert>
<update id="updateBook">
UPDATE book SET bookname=#{bookName},bookauthor=#{bookAuthor},bookprice=#{bookPrice} WHERE bookid=#{bookID}
</update>
<delete id="deleteBook">
DELETE FROM book WHERE bookid=#{bookID}
</delete>
<select id="findOneBookByPK" resultType="Book">
SELECT * FROM book WHERE bookid=#{bookID}
</select>
</mapper> 下面我说一下这个xml中要注意的点，
mapper中的属性namespace的值就是刚才和这个同名的dao的全类名
其中的id要写成你刚才那个接口里的方法名，mybatis的这种方法这儿需要这么干，resultType="Book"，这儿他是返回值类型，他这儿默认得写全类名，例如"cn.dawn.day01.entity.Book",
但是我这儿经过一个处理，它可以直接写成book，这个小知识点叫别名，稍微引一下，这儿放截图，截图好理解
parameterType=""这儿这个属性，我上面省略掉了，他的意思是什么呢，就是传进去的参数类型，刚才不是有个带参方法是根据id拿到所对应的书吗，这就可以写id的类型，但是这儿可以省略，所以我就不写了
准备工作都做完成之后，我们开始用单测的方式来进行单测
我下面把单测的方法放上来，使用的是较为原始的方式，更直接的剖析
import cn.dawn.demo01.entity.Book;
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.Test;
import java.io.IOException;
import java.io.InputStream;
import java.util.Iterator;
import java.util.List;
/**
* Created by Dawn on 2018/1/29.
*/
public class Test20180129 {
/*Logger logger=Logger.getLogger("xxx");*/
///查单独
@Test
public void t5findOne(){
/*logger.info("这是查单独");*/
String path = "mybatis-config.xml";
try {
InputStream e = Resources.getResourceAsStream(path);
SqlSessionFactoryBuilder builder = new SqlSessionFactoryBuilder();
SqlSessionFactory factory = builder.build(e);
SqlSession session = factory.openSession();
Book book = session.selectOne("findOneBookByPK", 1);
System.out.println("书名"+book.getBookName());
session.close();
} catch (IOException var9) {
var9.printStackTrace();
}
}
///删除
@Test
public void t4delete(){
String path = "mybatis-config.xml";
try {
InputStream e = Resources.getResourceAsStream(path);
SqlSessionFactoryBuilder builder = new SqlSessionFactoryBuilder();
SqlSessionFactory factory = builder.build(e);
SqlSession session = factory.openSession();
int count123 = session.delete("deleteBook",4);
session.commit();
System.out.println(count123);
session.close();
} catch (IOException var9) {
var9.printStackTrace();
}
}
///修改
@Test
public void t3update(){
String path = "mybatis-config.xml";
try {
InputStream e = Resources.getResourceAsStream(path);
SqlSessionFactoryBuilder builder = new SqlSessionFactoryBuilder();
SqlSessionFactory factory = builder.build(e);
SqlSession session = factory.openSession();
Book book=new Book();
book.setBookID(4);
book.setBookName("心想事成888");
int count123 = session.update("updateBook", book);
session.commit();
System.out.println(count123);
session.close();
} catch (IOException var9) {
var9.printStackTrace();
}
}
///添加
@Test
public void t2Insert(){
String path = "mybatis-config.xml";
try {
InputStream e = Resources.getResourceAsStream(path);
SqlSessionFactoryBuilder builder = new SqlSessionFactoryBuilder();
SqlSessionFactory factory = builder.build(e);
SqlSession session = factory.openSession();
Book book=new Book();
book.setBookName("心想事成");
book.setBookAuthor("孟六");
book.setBookPrice(999);
int count123 = session.insert("insertBook", book);
session.commit();
System.out.println(count123);
session.close();
} catch (IOException var9) {
var9.printStackTrace();
}
}
///查全部
@Test
public void t1SelectAll(){
String path = "mybatis-config.xml";
try {
InputStream e = Resources.getResourceAsStream(path);
SqlSessionFactoryBuilder builder = new SqlSessionFactoryBuilder();
SqlSessionFactory factory = builder.build(e);
SqlSession session = factory.openSession();
List lists = session.selectList("findAllBook");
Iterator var7 = lists.iterator();
while(var7.hasNext()) {
Book book = (Book)var7.next();
System.out.println(book.getBookName() + "\t" + book.getBookAuthor());
}
session.close();
} catch (IOException var9) {
var9.printStackTrace();
}
}
} 只有selectOne需要看一下，他是查单个的意思，别的都比较好理解，有的前一个博客有写，有的从字面意思就可以理解
增删改查就此结束