MyBites學習第一講,增刪改查
阿新 • • 發佈:2017-07-28
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一、準備開發環境
安裝jdk,下載一個eclipse,這裏就不多講啦
二、創建一個java項目,將下面的包導入到lib中並編譯
具體怎麽講包導入並編譯我這裏稍微講一下:選中項目右鍵——Build Path——Configure Build Path——Libraries
先添加jdk:
點擊Finish 就講jdk加到環境中了,然後添加jar包:
OK,到了這步運行環境已經搭建好了,那麽開始操作吧。
三、創建sqlMapConfig.xml
首先你要在src下創建一個sqlMapConfig.xml文件,有人問了為啥叫這名?能改不?我可以告訴你這就是一種約定,就和hibernate的hibernate.cfg.xml一樣,當然也可以自定義,目前沒必要改。
<?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> <!-- <context:property-placeholder location="classpath:*.properties"/> --> <environments default="development"> <environment id="development"> <transactionManager type="JDBC" /> <dataSource type="POOLED"><!-- 指定類型為連接池 --> <!--數據源信息 --> <property name="driver" value="com.mysql.jdbc.Driver"/> <property name="url" value="jdbc:mysql://192.168.1.68:3306/test?characterEncoding=utf-8"/> <property name="username" value="root"/> <property name="password" value="root"/> </dataSource> </environment> </environments> <mappers> <mapper resource="cn/core/domain/User.xml" /> </mappers> </configuration>
四、數據庫創建一張表(user,這裏隨便我演示所以叫user)
隨便創建了4個字段:
四、創建User(實體類)對象
package cn.core.domain; import java.io.Serializable; import java.sql.Timestamp; /** * 用戶實體類. * * @ClassName: User * @author [email protected] * @date: 2016年4月29日 上午8:22:09 * @version V1.0 */ public class User implements Serializable {User//主鍵ID private String user_id; //用戶的名字 private String uname; //地址 private String address; //年齡 private int age; public String getUser_id() { return user_id; } public void setUser_id(String user_id) { this.user_id = user_id; } public String getUname() { return uname; } public void setUname(String uname) { this.uname = uname; } public String getAddress() { return address; } public void setAddress(String address) { this.address = address; } public int getAge() { return age; } public void setAge(int age) { this.age = age; } @Override public String toString() { return "User [user_id=" + user_id + ", uname=" + uname + ", address=" + address + ", age=" + age + "]"; } }
五、創建User.xml對象
註意這裏創建User.xml就是在sqlMapConfig.xml中引入的節點,回顧一下:
<mappers> <mapper resource="cn/core/domain/User.xml" /> </mappers>
具體的User.xml文件:
<?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.core.domain.User"> <!-- 查詢單個對象 --> <select id="selectUserById" parameterType="string" resultType="cn.core.domain.User"> select * from user where user_id = #{user_id} </select> <!-- 添加 --> <insert id="insertUser" parameterType="cn.core.domain.User" > insert into user values(#{user_id},#{uname},#{address},#{age}) </insert> <!-- 修改 --> <update id="updateUser" parameterType="cn.core.domain.User"> update user set uname=#{uname},address=#{address},age=#{age} where user_id=#{user_id} </update> <!-- 刪除 --> <delete id="deleteUser" parameterType="string" > delete from user where user_id=#{user} </delete> </mapper>
六、測試文件MyBitesTest.java文件
package cn.test; import java.io.IOException; import java.io.InputStream; import java.util.UUID; 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 cn.core.domain.User; public class MyBitesTest { SqlSessionFactory sf ; @Before public void initSessionFactory() throws Exception{ String resource = "sqlMapConfig.xml"; InputStream inputStream = Resources.getResourceAsStream(resource); //獲得會話工廠 sf = new SqlSessionFactoryBuilder().build(inputStream); } @Test public void selectUserById() throws IOException{ SqlSession session=sf.openSession(); User user=(User)session.selectOne("cn.core.domain.User.selectUserById", "1"); System.out.println(user); } @Test public void insertByUser() throws IOException{ SqlSession session=sf.openSession(); User user=new User(); user.setUser_id(UUID.randomUUID().toString()); user.setAge(33); user.setAddress("海澱區"); user.setUname("李四"); int num=session.insert("cn.core.domain.User.insertUser", user); System.out.println("受影響的行數:"+num); session.commit(); } @Test public void updateUserById(){ SqlSession session=sf.openSession(); User user=new User(); user.setUser_id("1"); user.setAge(12); user.setUname("王五"); user.setAddress("西城區"); int num=session.update("cn.core.domain.User.updateUser", user); System.out.println("受影響的行數:"+num); session.commit(); } @Test public void deleteUserById(){ SqlSession session=sf.openSession(); int num=session.delete("cn.core.domain.User.deleteUser", "1687bd8c-ee4a-4bc2-8c99-246cd08295cb"); System.out.println("受影響的行數:"+num); session.commit(); } }
註意:session對象下selectOne、insert、update、delete 等等 這些方法如果是2個參數的,第一個參數是你配置的xml中對應的命名空間+id名字,例如:User.xml的命名空間是cn.core.domain.User,對應的方法找對應的id,例如查詢操作 這樣表示:cn.core.domain.User.selectUserById
完整項目下載地址:http://pan.baidu.com/s/1qYrz7Ne
MyBites學習第一講,增刪改查