mybaits输出helloworld-------mybatis(二)，springboot入门最详细教程

<?xml version="1.0" encoding="UTF-8" ?>

• mybatis.properties配置文件，主要是为了解耦，

将数据库的主要信息单独维护，从而减小configuration文件的同事，

若有多个数据库配置，也方便进行更换。

jdbc.driver=com.mysql.cj.jdbc.Driver

jdbc.url=jdbc:mysql://你的服务器IP:3306/mybatis_database?characterEncoding=utf-8

jdbc.username=root

jdbc.password=root

• BlogMapper.xml 文件主要负责将实体类映射到数据库中

<?xml version="1.0" encoding="UTF-8" ?>

select * from mybatis_test where id = #{id}

• log4j.properties 主要定义的是各种运行输出信息，调试信息和错误信息，各位可根据实际需要修改到对应的目录

log4j.rootLogger = debug,stdout,D,E

###̧ 输出信息

log4j.appender.stdout = org.apache.log4j.ConsoleAppender

log4j.appender.stdout.Target = System.out

log4j.appender.stdout.layout = org.apache.log4j.PatternLayout

log4j.appender.stdout.layout.ConversionPattern = [%-5p] %d{yyyy-MM-dd HH:mm:ss,SSS} method:%l%n%m%n

调试信息

log4j.appender.D = org.apache.log4j.DailyRollingFileAppender

log4j.appender.D.File = F://logs/debug.log

log4j.appender.D.Append = true

log4j.appender.D.Threshold = DEBUG

log4j.appender.D.layout = org.apache.log4j.PatternLayout

log4j.appender.D.layout.ConversionPattern = %-d{yyyy-MM-dd HH:mm:ss} [ %t:%r ] - [ %p ] %m%n

错误信息

log4j.appender.E = org.apache.log4j.DailyRollingFileAppender

log4j.appender.E.File =F://logs

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/error.log

log4j.appender.E.Append = true

log4j.appender.E.Threshold = ERROR

log4j.appender.E.layout = org.apache.log4j.PatternLayout

log4j.appender.E.layout.ConversionPattern = %-d{yyyy-MM-dd HH:mm:ss} [ %t:%r ] - [ %p ]

5.编写java文件

• 实体类：Bloger.java，为了方便查看结果，这里我们重写toString

package model;

import org.apache.ibatis.type.Alias;

public class Bloger {

private Integer id;

private String name;

private String username;

private int age;

private String email;

public Integer getId() {

return id;

}

public void setId(Integer id) {

this.id = id;

}

public String getName() {

return name;

}

public void setName(String name) {

this.name = name;

}

public String getUsername() {

return username;

}

public void setUsername(String username) {

this.username = username;

}

public int getAge() {

return age;

}

public void setAge(int age) {

this.age = age;

}

public String getEmail() {

return email;

}

public void setEmail(String email) {

this.email = email;

}

@Override

public String toString() {

return “BlogId:”+ getId()+ " BlogName:"+getName()+ " UserName:" + getUsername();

}

}

• 编写接口文件 BlogMapper.java

package dao;

import model.Bloger;

public interface BlogerMapper {

//通过接口方法 getBlogerId（Integer id）返回一个实体对象

public Bloger getBlogerId(Integer id);

}

• 编写测试文件 MybatisDriver.java

package test;

import dao.BlogerMapper;

import model.Bloger;

import org.apache.ibatis.io.Resources;