IT修真院·坑乎 | Java(后端),CSS(前端),JavaScript(前端),PM(产品经理),UI(交互设计),QA(测试),Android(安卓APP),iOS(苹果APP),OP(运维),Python(后端)日常在线问答学习平台

字段的长度设置为了1，但是数据库里面还是可以显示超过1的长度

0

1

DB设计

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

log4j的配置文件

0

1

log4j

class="cursor-pointer"> 详细描述

环境配置失败

0

1

mybatis

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

mybatis和spring整合JDBC报错获取不到

0

1

mybatis

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

spring整合mybatis中log4j的配置

0

1

log4j mybatis

class="cursor-pointer"> 详细描述

坑乎没法搜索

1

class="cursor-pointer"> 详细描述

整合spring-mybatis

1

mybatis spring

class="cursor-pointer"> 详细描述

myabtis.xml

0

1

class="cursor-pointer"> 详细描述

映射文件问题

1

mybatis

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

Mybatis整合Spring测试空指针

0

1

mybatis spring

class="cursor-pointer"> 详细描述

1.导入相应的包

MyBatis 的包（MyBatis 3.4.6）
Spring 的 jar 包（Spring 4.3.15）
MyBatis 与 Spring 的整合 jar 包（mybatis-spring 1.3.2）
mysql-connector-java-5.1.21.
2.创建Student实体类

package com.mybatis4.pojo;

public class Student {
private String name;
private String sex;
private int age;
private String school;
private long id;

//初始化Student

public Student() {
   }
//定义有参构造
public Student(String name, String sex, int age, long id, String school) {
this.name = name;
this.sex = sex;
this.age = age;
this.id = id;
this.school = school;
   }

public String getName() {
return name;
   }

public void setName(String name) {
this.name = name;
   }

public String getSex() {
return sex;
   }

public void setSex(String sex) {
this.sex = sex;
   }

public int getAge() {
return age;
   }

public void setAge(int age) {
this.age = age;
   }

public String getSchool() {
return school;
   }

public void setSchool(String school) {
this.school = school;
   }

public long getId() {
return id;
   }

public void setId(long id) {
this.id = id;
   }

@Override
   public String toString() {
return "Student{" +
"name='" + name + '\'' +
", sex='" + sex + '\'' +
", age=" + age +
", school='" + school + '\'' +
", id=" + id +
'}';
   }
}
3.创建db.properties数据库连接信息

jdbc.driver=com.mysql.cj.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/test?characterEncoding=UTF-8
jdbc.username=root
jdbc.password=admin123
4.创建StudentDao

package com.mybatis4.dao;

import com.mybatis4.pojo.Student;

import java.util.List;

public interface StudentDao {
public int insertMethod(Student student);
public int deleteMethod(Student name);
public int updateMethod(Student student);
public Student findMethodById(long id);
public List<Student> findAllStudent();

}
5.编写Spring配置文件sqlSessionFactory.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      xmlns:context="http://www.springframework.org/schema/context"
      xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd">

   <context:property-placeholder location="db.properties"/>

   <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="${jdbc.driver}"/>
<property name="url" value="${jdbc.url}"/>
<property name="username" value="${jdbc.username}"/>
<property name="password" value="${jdbc.password}"/>
</bean>

   
   
       
       
   <bean id="sqlSessionFactoryBean" class="org.mybatis.spring.SqlSessionFactoryBean">
<property name="configLocation" value="Mybatis-config.xml"/>
<property name="dataSource" ref="dataSource"/>
</bean>

</beans>
6.编写Mybatis配置文件Mybatis-config.xml

<?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>
<typeAlias type="com.mybatis4.pojo.Student" alias="student"/>
</typeAliases>
<mappers>
<mapper resource="Mapper.xml"/>
</mappers>
</configuration>
7.编写映射文件Mapper.xml

<?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>
<typeAlias type="com.mybatis4.pojo.Student" alias="student"/>
</typeAliases>
<mappers>
<mapper resource="Mapper.xml"/>
</mappers>
</configuration>
8.创建接口实现类StudentDaoImpl

package com.mybatis4.studentDaoImpl;

import com.mybatis4.dao.StudentDao;
import com.mybatis4.pojo.Student;
import org.mybatis.spring.support.SqlSessionDaoSupport;

import java.util.List;
public class StudentDaoImpl extends SqlSessionDaoSupport implements StudentDao {

public int insertMethod(Student student) {
return this.getSqlSession().insert("test.insertMethod",student);
}

public int deleteMethod(Student name) {
return this.getSqlSession().insert("test.deleteMethod","ksy");
}

public int updateMethod(Student student) {
return this.getSqlSession().insert("test.deleteMethod",student);
}

public Student findMethodById(long id) {
return this.getSqlSession().selectOne("test.findMethodById,id");
}

public List<Student> findAllStudent() {
return this.getSqlSession().selectList("test.findAllStudent");
}
}
9.编写测试类

package test;

import com.mybatis4.dao.StudentDao;
import com.mybatis4.pojo.Student;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class Test {
private ApplicationContext context;
//加载Mybatis-config配置文件
   public void setUp() throws Exception{
context = new ClassPathXmlApplicationContext("Mybatis-config.xml");
}
@org.junit.Test
   public  void insertMethod(){
StudentDao studentDao= (StudentDao) context.getBean("studentDao");
Student student=new Student("ksy","male",10,20,"wcsy");
studentDao.insertMethod(student);
}
}

class="cursor-pointer"> 错误截图