今日完成的事：

1，学习log4j

  a.导入jar包

  b.使用log4j

2，学习Spring与Mybatis的整合。

    a. pojo 

public class Category {
    private int id;
    privat
e 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;
    }

    @Override
    public String toString() {
        return "Category{" +
                "id=" + id +
                ", name='" + name + '\'' +
                '}';
    }
}

‍‍b.Mapper

public interface CategoryMapper {
    public int add(Category category);

    public void delete(int id);

    public Category get(int id);

    public int update(Category category);

    public List<Category> list();

    public int count();

‍‍c.Category.xml  要和上一个CategoryMapper类放在同一个包下

<?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.how2java.mapper.CategoryMapper">
    <insert id="add" parameterType="Category" >
        insert into category( name ) values (#{name})
    </insert>

    <delete id="delete" parameterType="Category" >
        delete from category where id= #{id}
    </delete>

    <select id="get" parameterType="_int" resultType="Category">
        select * from   category where id= #{id}
    </select>

    <update id="update" parameterType="Category" >
        update category set name=#{name} where id=#{id}
    </update>
    <select id="list" resultType="Category">
        select * from  category
    </select>
</mapper>

d.applicationContext.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:aop="http://www.springframework.org/schema/aop"
       xmlns:tx="http://www.springframework.org/schema/tx" xmlns:jdbc="http://www.springframework.org/schema/jdbc"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xsi:schemaLocation="
     http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd
     http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
     http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc-3.0.xsd
     http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
     http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd
     http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd">

    <context:annotation-config />

    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName">
            <value>com.mysql.jdbc.Driver</value>
        </property>
        <property name="url">
            <value>jdbc:mysql://localhost:3306/how2java?characterEncoding=UTF-8</value>

        </property>
        <property name="username">
            <value>root</value>
        </property>
        <property name="password">
            <value>123456</value>
        </property>
    </bean>

    <bean id="sqlSession" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="typeAliasesPackage" value="com.how2java.pojo" />
        <property name="dataSource" ref="dataSource"/>
        <property name="mapperLocations" value="classpath:com/how2java/mapper/*.xml"/>
    </bean>

    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <property name="basePackage" value="com.how2java.mapper"/>
    </bean>

</beans>

<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">

--配置连接数据库的驱动，URL，账号和密码

<bean id="sqlSession" class="org.mybatis.spring.SqlSessionFactoryBean">

--扫描XML配置文件

<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">

--扫描Mapper类

e.测试

package com.java.test;

import com.how2java.mapper.CategoryMapper;
import com.how2java.pojo.Category;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

import java.util.List;

/**
 * Created by linshimingyi on 2017/5/10.
 */
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:applicationContext.xml")
public class MybatisTest {

    @Autowired
    private CategoryMapper categoryMapper;

    @Test
    public void testAdd() {
        Category category = new Category();
        category.setName("new Category");
        categoryMapper.add(category);
    }

    @Test
    public void testList() {
        System.out.println(categoryMapper);
        List<Category> cs=categoryMapper.list();
        for (Category c : cs) {
            System.out.println(c.getName());
        }
    }

}

运行结果：java.lang.AbstractMethodError: org.mybatis.spring.transaction.SpringManagedTransaction.getTimeout()Ljava/lang/Integer;

排查后找到原因：jar包中mybatis有两个，删除后正常运行。

疑惑：问题复现时，却可以正常运行。

明日计划：

学习SpringMVC和SSM。

遇到的问题：

今儿遇到的两个问题都与jar包有关。

1，上午在复习mybatis时，遇到NoClassDefFoundError，原因是程序中用到了单元测试，导包时只导了juni-jart包，忘记到hamcrest-core-jar了。

2，下午遇到的问题前面已经体现了，也是因为包的缘故。