SSM（Spring+SpringMVC+MyBatis）框架学习心路历程【一】

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
@Id
public 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;
}

@Override
public 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;
}

@Override
public 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,password
FROM `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 {

@Autowired
CartoonMapper 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{

@Autowired
CartoonService cartoonService;

//测试新增动漫
@Test
public  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
@Test
public 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
@Test
public void testDelete() throws SSException{
cartoonService.deleteById(8);
}

//测试全部动漫信息条数
@Test
public void testCountAll() throws SSException{
System.out.println(cartoonService.countAll());
}

//测试根据ID查询动漫信息
@Test
public void testQueryById() throws SSException {
System.out.println(cartoonService.queryById(3));
}

//测试根据名称查询动漫信息
@Test
public 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！