Mybatis基础：增删改查、模糊查询、多条件查询-低调大师

Mybatis基础：增删改查、模糊查询、多条件查询

2018-04-15 795

Mybatis基础：增删改查、模糊查询、多条件查询http://www.bieryun.com/3132.html

1、新建测试数据库，根据实体类属性创建

2、实体类

[java] view plain copy

package com.entity;
/**
* 数据库实体类
* Created by lvjun on 2018-04-12.
*/
public class Category {
private int id;
private String name;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
//显示中文
@Override
public String toString() {
return "Category{" +
"id=" + id +
", name='" + name + '\'' +
'}';
}
}

3、配置文件Category.xml

[html] view plain copy

<?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.entity">
<select id="listCategory" resultType="Category">
select * from category
</select>
<delete id="deleteCategory" parameterType="Category">
delete from category where id= #{id}
</delete>
<select id="getCategory" parameterType="_int" resultType="Category">
select * from category where id= #{id}
</select>
<update id="updateCategory" parameterType="Category">
update category set name=#{name} where id=#{id}
</update>
<insert id="addCategory" parameterType="Category">
insert into category ( name ) values (#{name})
</insert>
<select id="listCategoryByName" parameterType="string" resultType="Category">
select * from category where name like concat('%',#{0},'%')
</select>
<select id="listCategoryByIdAndName" resultType="Category">
select * from category
<where>
<if test="id!=null">
and id > #{id}
</if>
<if test="name!=null">
and name like concat('%',#{name},'%')
</if>
</where>
</select>
</mapper>

4、配置文件mybatis-config.xml

[html] view plain copy

<?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>
<typeAliases>
<package name="com.entity"/>
</typeAliases>
<environments default="development">
<environment id="development">
<transactionManager type="JDBC"/>
<dataSource type="POOLED">
<property name="driver" value="com.mysql.jdbc.Driver"/>
<property name="url" value="jdbc:mysql://localhost:3306/school?characterEncoding=UTF-8"/>
<property name="username" value="root"/>
<property name="password" value="1234"/>
</dataSource>
</environment>
</environments>
<mappers>
<mapper resource="Category.xml"/>
</mappers>
</configuration>

5、测试类

[java] view plain copy

package com.lvjun;
import com.entity.Category;
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 java.io.IOException;
import java.io.InputStream;
import java.util.List;
/**
* 查询列表
* Created by lvjun on 2018-04-12.
*/
public class TestSelectList {
public static void main(String[] args) throws IOException {
String resource = "mybatis-config.xml";
InputStream inputStream = Resources.getResourceAsStream(resource);
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
SqlSession session = sqlSessionFactory.openSession();
List<Category> cs = session.selectList("listCategory");
for (Category c : cs) {
System.out.println(c.getId()+" "+c.getName());
}
}
}

[java] view plain copy

package com.lvjun;
import com.entity.Category;
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 java.io.IOException;
import java.io.InputStream;
import java.util.List;
/**
* 查询一条记录
* Created by lvjun on 2018-04-12.
*/
public class TestSelectOne {
public static void main(String[] args) throws IOException {
String resource = "mybatis-config.xml";
InputStream inputStream = Resources.getResourceAsStream(resource);
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
SqlSession session = sqlSessionFactory.openSession();
Category c = session.selectOne("getCategory", 3);
System.out.println(c.getId()+" "+c.getName());
session.commit();
session.close();
}
}

[java] view plain copy

package com.lvjun;
import com.entity.Category;
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 java.io.IOException;
import java.io.InputStream;
import java.util.List;
/**
* 模糊查询
* Created by lvjun on 2018-04-12.
*/
public class TestSelectLike {
public static void main(String[] args) throws IOException {
String resource = "mybatis-config.xml";
InputStream inputStream = Resources.getResourceAsStream(resource);
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
SqlSession session = sqlSessionFactory.openSession();
List<Category> cs = session.selectList("listCategoryByName", "win");
for (Category c : cs) {
System.out.println(c.getId()+" "+c.getName());
}
session.commit();
session.close();
}
}

[java] view plain copy

package com.lvjun;
import java.io.IOException;
import java.io.InputStream;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import com.entity.Category;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
/**
* 多条件查询
* Created by lvjun on 2018-04-12.
*/
public class TestSelectToLike {
public static void main(String[] args) throws IOException {
String resource = "mybatis-config.xml";
InputStream inputStream = Resources.getResourceAsStream(resource);
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
SqlSession session = sqlSessionFactory.openSession();
Map<String, Object> params = new HashMap<>();
params.put("id", 3); //条件查询
params.put("name", "wi");
List<Category> cs = session.selectList("listCategoryByIdAndName", params);
for (Category c : cs) {
System.out.println(c.getId()+" "+c.getName());
}
session.commit();
session.close();
}
}

[java] view plain copy

package com.lvjun;
import com.entity.Category;
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 java.io.IOException;
import java.io.InputStream;
import java.util.List;
/**
* 修改记录
* Created by lvjun on 2018-04-12.
*/
public class TestUpdate {
public static void main(String[] args) throws IOException {
String resource = "mybatis-config.xml";
InputStream inputStream = Resources.getResourceAsStream(resource);
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
SqlSession session = sqlSessionFactory.openSession();
Category c = session.selectOne("getCategory", 2);
c.setName("Android 8");
session.update("updateCategory", c);
listAll(session);
session.commit();
session.close();
}
private static void listAll(SqlSession session) {
List<Category> cs = session.selectList("listCategory");
for (Category c : cs) {
System.out.println(c.getId()+" "+c.getName());
}
}
}

[java] view plain copy

package com.lvjun;
import com.entity.Category;
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 java.io.IOException;
import java.io.InputStream;
import java.util.List;
/**
* 插入一条记录
* Created by lvjun on 2018-04-12.
*/
public class TestInsert {
public static void main(String[] args) throws IOException {
String resource = "mybatis-config.xml";
InputStream inputStream = Resources.getResourceAsStream(resource);
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
SqlSession session = sqlSessionFactory.openSession();
Category c = new Category();
c.setName("新增加的数据");
session.insert("addCategory", c);
listAll(session);
session.commit();
session.close();
}
private static void listAll(SqlSession session) {
List<Category> cs = session.selectList("listCategory");
for (Category c : cs) {
System.out.println(c.getId()+" "+c.getName());
}
}
}

[java] view plain copy

package com.lvjun;
import com.entity.Category;
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 java.io.IOException;
import java.io.InputStream;
import java.util.List;
/**
* 删除一条记录
* Created by lvjun on 2018-04-12.
*/
public class TestDeleteOne {
public static void main(String[] args) throws IOException {
String resource = "mybatis-config.xml";
InputStream inputStream = Resources.getResourceAsStream(resource);
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
SqlSession session = sqlSessionFactory.openSession();
Category c = new Category();
c.setId(6);
session.delete("deleteCategory", c);
listAll(session);
session.commit();
session.close();
}
private static void listAll(SqlSession session) {
List<Category> cs = session.selectList("listCategory");
for (Category c : cs) {
System.out.println(c.getId()+" "+c.getName());
}
}
}

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