项目简介
项目的经典模块-C（Create 创建）R（Retrieve 查询）U（Update 更新）D（Delete 删除）功能使用技术 ssm：SpringMVC+Spring+Mybatis
sql数据库的设计
create database crud
;
use crud
;
create table department
(
did
int primary key auto_increment,
dname
varchar(20)
)
insert into department
values(null,'java');
insert into department
values(null,'测试');
insert into department
values(null,'需求');
create table employee
(
eid
int primary key auto_increment,
ename
varchar(20),
gender
varchar(20),
did
int
)
insert into employee
values(null,'jack','1',1);
insert into employee
values(null,'rose','1',1);
insert into employee
values(null,'tony','1',2);
ssm搭建
复制搭建好的SSM为SSM_CRUD项目（如果是复制原来的项目，记得修改pom.xml，我这里用的是原来的项目，所以并不进行修改）
代码编写
查询后台代码：保证数据正确
TestDepartmentService
@RunWith(SpringJUnit4ClassRunner
.class)
@ContextConfiguration("classpath:applicationContext.xml")
public class TestDepartment {
private static final Logger l
= LoggerFactory
.getLogger(TestDepartment
.class);
@Qualifier("departmentServiceImpl")
@Autowired
IDepartmentService service
;
@Test
public void test01(){
List
<Department> list
= service
.findAllDepartment();
l
.info("test01 list="+list
);
}
Department
public class Department {
private Integer did
;
private String dname
;
public Department() {
}
public Department( String dname
) {
this.dname
= dname
;
}
@Override
public String
toString() {
return "Department{" +
"did=" + did
+
", dname='" + dname
+ '\'' +
'}';
}
IDepartmentService
@Service
public interface IDepartmentService {
List
<Department> findAllDepartment();
DepartmentServiceImpl
@Service
public class DepartmentServiceImpl implements IDepartmentService {
@Autowired
IDepartmentDao dao
;
@Override
public List
<Department> findAllDepartment() {
List
<Department> list
= dao
.findAll();
return list
;
}
IDepartmentDao
public interface IDepartmentDao {
List
<Department> findAll();
}
IDepartmentDao.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.wxx.dao.IDepartmentDao">
<select id="findAll" resultType="department">
select * from department;
</select>
</mapper>
查询前台代码：显示
DepartmentController
@Controller
@RequestMapping("/dept")
public class DepartmentController {
private static final Logger l
= LoggerFactory
.getLogger(DepartmentController
.class);
@Qualifier("departmentServiceImpl")
@Autowired
private IDepartmentService iDepartmentService
;
@RequestMapping(path
= "/list",method
= RequestMethod
.GET
)
public String
list(Model model
){
List
<Department> depts
= iDepartmentService
.findAllDepartment();
l
.info("list depts="+depts
);
model
.addAttribute("depts",depts
);
return "list_depts";
}
list_depts.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" isELIgnored="false" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<html>
<head>
<title>Title
</title>
</head>
<body>
<a href="">新增
</a>
<table border="1px" width="100%">
<tr>
<td>编号
</td>
<td>部门名称
</td>
<td>管理
</td>
</tr>
<c:forEach items="${depts}" var="dept">
<tr>
<td>${dept.did}
</td>
<td>${dept.dname}
</td>
<td><a href="">删除
</a><a href="">修改
</a></td>
</tr>
</c:forEach>
</table>
</body>
</html>
添加部门功能的后台代码
TestDepartmentSservice
@Test
public void test02(){
Department dept
= new Department("UI设计部门");
service
.saveDepartment(dept
);
}
IDepartmentService
void saveDepartment(Department dept
);
DepartmentServiceImpl
@Override
public void saveDepartment(Department dept
) {
dao
.save(dept
);
}
IDepartmentDao
void save(Department dept
);
IDepartmentDao.xml
<insert id="save" parameterType="department">
insert into department values(null,#{dname});
</insert>
添加功能的前台代码
DepartmentController
@RequestMapping(path
= "/addUI",method
= RequestMethod
.GET
)
public String
addUI(){
l
.info("addUI");
return "add_dept";
}
list_depts.jsp
<a href="${pageContext.request.contextPath}/dept/addUI">新增
</a>
add_dept.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" isELIgnored="false" %>
<html>
<head>
<title>添加部门
</title>
</head>
<body>
<form method="post" action="${pageContext.request.contextPath}/dept/save">
<input type="text" name="dname"/><br/>
<input type="submit" value="保存"/><br/>
</form>
</body>
</html>
删除功能实现的后台代码
TestDepartmentService
@Test
public void test03(){
service
.deleteDepartmentById(3);
}
IDepartmentService
void deleteDepartmentById(int i
);
DepartmentServiceImpl
@Override
public void deleteDepartmentById(int id
) {
dao
.deleteById(id
);
}
IDepartmentDao
void deleteById(int id
);
IDepartmentDao.xml
<delete id="deleteById" parameterType="int">
delete from department where did = #{id};
</delete>
删除功能实现的前台代码
DepartmentController
@RequestMapping(path
= "/delete",method
= RequestMethod
.GET
)
public String
delete(Integer did
){
l
.info("delete did="+did
);
iDepartmentService
.deleteDepartmentById(did
);
return "redirect:/dept/list";
}
list_depts.jsp
<a href="${pageContext.request.contextPath}/dept/delete?did=${dept.did}">删除
</a>
修改功能实现的后台代码
修改功能，需要在打开页面的同时，查询一下数据，把数据带到页面进行同赋值，这操作叫做回显
TestDepartmentService
@Test
public void test04(){
Department dept
=new Department();
dept
.setDid(4);
dept
.setDname("开发");
service
.updateDepartmentById(dept
);
}
@Test
public void test05(){
Department dept
= service
.findDepartmentById(1);
l
.info("test05 dept= "+dept
);
}
IDepartmentService
void updateDepartmentById(Department dept
);
Department
findDepartmentById(int did
);
DepartmentServiceImpl
@Override
public void updateDepartmentById(Department dept
) {
dao
.update(dept
);
}
@Override
public Department
findDepartmentById(int did
) {
return dao
.findById(did
);
}
IDepartmentDao
void update(Department dept
);
Department
findById(int did
);
IDepartmentDao.xml
<delete id="update" parameterType="department">
update department set dname = #{dname} where did = #{did};
</delete>
<select id="findById" parameterType="int" resultType="department">
select * from department where did = #{did};
</select>
修改功能实现的前台代码
DepartmentController
@RequestMapping(path
= "/updateUI",method
= RequestMethod
.GET
)
public String
updateUI(Integer did
,Model model
){
l
.info("updateUI did = "+ did
);
Department department
= iDepartmentService
.findDepartmentById(did
);
model
.addAttribute("dept",department
);
return "update_dept";
}
@RequestMapping(path
= "/update" ,method
= RequestMethod
.POST
)
public String
update(Department dept
){
l
.info("update dept="+dept
);
iDepartmentService
.updateDepartmentById(dept
);
return "redirect:/dept/list";
}
list_depts.jsp
<a href="${pageContext.request.contextPath}/dept/updateUI?did=${dept.did}">修改
</a>
update_dept.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" isELIgnored="false" %>
<html>
<head>
<title>Title
</title>
</head>
<body>
<form method="post" action="${pageContext.request.contextPath}/dept/update">
<input type="hidden" name="did" value="${dept.did}">
<input type="text" value="${dept.did}" disabled="disabled"><br/>
<input type="text" name="dname" value="${dept.dname}"><br/>
<input type="submit" value="保存修改">
</form>
</body>
</html>
