SSM（Spring+SpringMVC+MyBatis）框架入门

最近，开始SSM框架的学习，经过三四天与代码的厮杀后，终于学会了，在SSM框架中写 增删改查（数据库），今天controller写不下去了，就和大家先分享下经验，再与其相爱相杀吧！

对，（蓝瘦在这里，香菇），忘了说，
数据库是mysql，而且用了Navicat可视化工具
IDE是idea，听说是最好用的编译器

首先，教大家如何打开一个SSM项目

这里，framework就是我们要打开的项目，选择最外面的pom.xml（如图所示），来打开整个项目。

接着，展示一下目录

这个是大体上的目录，大概有.idea(自动生成)，service，web三大目录

第一步，开始数据库的连接

在web目录下，按照左侧目录所示，一步步找到database-config.xml文件，点击打开，在

 <property name="jdbcUrl" value="jdbc:mysql://localhost:3306/db_cartoon? ..../>

db_cartoon的位置上换上自己建立的数据库，其他的不用管，都是MyBatis里面的语句。

第二步，写实体类

在service目录下，打开Cartoon文件，把数据库里面有的字段都写出来。

package com.pandawork.common.entity;import com.pandawork.core.common.entity.AbstractEntity;
import com.sun.jmx.snmp.Timestamp;import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Table;import static com.sun.xml.internal.ws.policy.sourcemodel.wspolicy.XmlToken.Name;/*** Cartoon实体* Created by 阿鑫 on 2016/11/4.*/
@Table(name = "t_cartoon")
@Entity
public  class Cartoon extends AbstractEntity {   //为什么要继承AbstractEntity 呢？//动漫类别的序号@Idpublic Integer id;//这个得研究下//动漫类别的名称@Column(name = "name")private String name;//动漫的ID@Column(name = "p_id")private  Integer pId;//动漫的名称@Column(name = "p_name")private String pName;//动漫的作者@Column(name = "author")private String author;//动漫的介绍@Column(name = "description")private  String description;//创建时间@Column(name = "created_time")private Timestamp createdTime;//最后修改的时间public Timestamp getCreatedTime() {return createdTime;}public void setCreatedTime(Timestamp createdTime) {this.createdTime = createdTime;}public Timestamp getLastModifiedTime() {return lastModifiedTime;}public void setLastModifiedTime(Timestamp lastModifiedTime) {this.lastModifiedTime = lastModifiedTime;}@Column(name = "last_modified_time")private Timestamp lastModifiedTime;public Integer getId() {return id;}@Overridepublic void setId(Integer id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}public Integer getpId() {return pId;}public void setpId(Integer pId) {this.pId = pId;}public String getpName() {return pName;}public void setpName(String pName) {this.pName = pName;}public String getAuthor() {return author;}public void setAuthor(String author) {this.author = author;}public String getDescription() {return description;}public void setDescription(String description) {this.description = description;}@Overridepublic String toString() {return "Cartoon{" +"id=" + id +", name='" + name + '\'' +", pId=" + pId +", pName='" + pName + '\'' +", author='" + author + '\'' +", description='" + description + '\'' +'}';}}

第二步，开始写mapper文件和其对应的mapper.xml

在service目录下，打开CartoonMapper文件

package com.pandawork.mapper;import com.pandawork.common.entity.Cartoon;
import com.pandawork.common.entity.Student;
import com.pandawork.core.common.exception.SSException;
import org.apache.ibatis.annotations.Param;import java.util.List;/*** 动漫管理mapper层* Created by ${阿鑫} on 2016/11/4.*/
public interface CartoonMapper {/*** 增加动漫信息* @param cartoon* @throws Exception*/public void insert(@Param("cartoon") Cartoon cartoon) throws Exception;/*** 修改动漫信息* @param cartoon* @return* @throws Exception*/public void update(@Param("cartoon") Cartoon cartoon) throws Exception;/***删除动漫信息* @param id* @return* @throws Exception*/public boolean deleteById(@Param("id") int id) throws Exception;/*** 全部动漫信息条数* @return* @throws SSException*/public int countAll() throws Exception;/*** 查询动漫的数目* @param id* @return* @throws SSException*/public Cartoon queryById(@Param("id") int id) throws Exception;/*** 搜素Name中的字符* @param cartoonPName* @return* @throws SSException*/public Cartoon queryByPName(@Param("cartoonPName") String cartoonPName) throws Exception;}

对应的mapper.xml

<?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.pandawork.mapper.UserMapper"><insert id="insert">INSERT INTO `t_user`(`username`,`password`)VALUES(#{user.username},#{user.password})</insert><delete id="delete">DELETE FROM `t_user`WHERE id = #{id}</delete><update id="update">UPDATE `t_user`SET `username` = #{user.username},`password` = #{user.password}WHERE id = #{user.id}</update><select id="queryById" resultMap="pw.User">SELECT id,username,passwordFROM `t_user`WHERE id = #{id}</select></mapper>

第三步，写service文件及其对应的实现serviceImpl

在service目录下，打开CartoonService文件

package com.pandawork.service;import com.pandawork.common.entity.Cartoon;
import com.pandawork.core.common.exception.SSException;/*** 动漫管理系统* CartoonService层* Created by ${阿鑫} on 2016/11/4.*/
public interface CartoonService {/*** 增加动漫信息* @param cartoon* @throws SSException*/public void insert(Cartoon cartoon) throws SSException;//SSException什么意思/*** 修改动漫信息* @param cartoon* @throws SSException*/public void update(Cartoon cartoon) throws SSException;/*** 删除动漫信息* @param id* @return* @throws SSException*/public boolean deleteById(int id) throws SSException;/*** 全部动漫信息条数* @return* @throws SSException*/public int countAll() throws SSException;/*** 根据id查询动漫的数目* @param id* @return* @throws SSException*/public Cartoon queryById(int id) throws SSException;/*** 搜素Name中的字符* @param cartoonPName* @return* @throws SSException*/public Cartoon queryByPName(String cartoonPName) throws SSException;
}

接着，打开对应的CartoonServiceImpl文件

package com.pandawork.service.impl;import com.pandawork.common.entity.Cartoon;
import com.pandawork.common.utils.NFException;
import com.pandawork.core.common.exception.SSException;
import com.pandawork.core.common.log.LogClerk;
import com.pandawork.core.common.util.Assert;
import com.pandawork.mapper.CartoonMapper;
import com.pandawork.service.CartoonService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Propagation;
import org.springframework.transaction.annotation.Transactional;/*** 动漫管理系统* CartoonService的实现* Created by ${阿鑫} on 2016/11/4.*/
@Service("cartoonService")//为啥要小写呀？
public class CartoonServiceImpl implements CartoonService {@AutowiredCartoonMapper cartoonMapper;public void insert(Cartoon cartoon) throws SSException {if (Assert.isNull(cartoon)) {return;}try {cartoonMapper.insert(cartoon);} catch (Exception e) {LogClerk.errLog.error(e);throw SSException.get(NFException.SystemException, e);}}@Transactional(propagation = Propagation.REQUIRED, rollbackFor = {SSException.class, Exception.class, RuntimeException.class})//只要对数据库有改动，就得写public void update(Cartoon cartoon) throws SSException {if(Assert.isNull(cartoon)){return;}try {cartoonMapper.update(cartoon);}catch (Exception e) {LogClerk.errLog.error(e);throw SSException.get(NFException.SystemException, e);}}@Transactional(propagation = Propagation.REQUIRED, rollbackFor = {SSException.class, Exception.class, RuntimeException.class})public boolean deleteById(int id) throws SSException {if (Assert.lessOrEqualZero(id)) {return false;}try {return cartoonMapper.deleteById(id);} catch (Exception e) {LogClerk.errLog.error(e);throw SSException.get(NFException.DelStudentNull, e);//先不改了，NFException这个要改哦！DelStudentNull要不然这个。。}}public int countAll() throws SSException {int count;try {count = cartoonMapper.countAll();}catch (Exception e){LogClerk.errLog.error(e);throw SSException.get(NFException.CountAll, e);}return count;}public Cartoon queryById(int id) throws SSException{if(Assert.lessOrEqualZero(id)) {return null;}try {return cartoonMapper.queryById(id);} catch (Exception e) {LogClerk.errLog.error(e);throw SSException.get(NFException.queryStudentByIdFailed, e);}}public Cartoon queryByPName(String cartoonPName) throws SSException {if(Assert.isNull(cartoonPName)) {return null;}try {return cartoonMapper.queryByPName(cartoonPName);} catch (Exception e){LogClerk.errLog.error(e);throw SSException.get(NFException.QueryByNameFailed, e);}}
}

第四步，测试增删改查四个方法

注意，这里test文件夹是绿色的，这是因为把这个test文件夹设置成了test sources root（设置方法如下图）

在web文件夹中，打开CartoonServiceTest文件。

package com.pandawork.test;import com.pandawork.common.entity.Cartoon;
import com.pandawork.core.common.exception.SSException;
import com.pandawork.service.CartoonService;
import org.junit.Test;
import org.springframework.beans.factory.annotation.Autowired;/*** 动漫管理系统* 测试service页面* CartoonService* Created by ${阿鑫} on 2016/11/4.*/
public class CartoonServiceTest  extends AbstractTestCase{@AutowiredCartoonService cartoonService;//测试新增动漫@Testpublic  void testInsert() throws SSException{Cartoon cartoon = new Cartoon();cartoon.setName("热血动漫");cartoon.setpId(999);cartoon.setpName("bigbang");cartoon.setAuthor("啦啦啦啦");cartoon.setDescription("哈哈");cartoonService.insert(cartoon);}//测试修改动漫@Testpublic void testUpdate() throws SSException{Cartoon cartoon = new Cartoon();cartoon.setName("教育动漫");cartoon.setpId(666);cartoon.setpName("大耳朵图图");cartoon.setAuthor("周月");cartoon.setDescription("动耳神功");cartoon.setId(1);cartoonService.update(cartoon);System.out.println(cartoon);}//测试删除动漫@Testpublic void testDelete() throws SSException{cartoonService.deleteById(8);}//测试全部动漫信息条数@Testpublic void testCountAll() throws SSException{System.out.println(cartoonService.countAll());}//测试根据ID查询动漫信息@Testpublic void testQueryById() throws SSException {System.out.println(cartoonService.queryById(3));}//测试根据名称查询动漫信息@Testpublic void testQueryByPName() throws SSException{System.out.println(cartoonService.queryByPName("大"));}
}

这个就是大概的流程和代码了！我试过了，几种方法都是可以跑通的，大家可以放心借鉴哈，在稍后的系列里会给大家讲述一些更加详细的东西。
谢谢观看！