SpringMVC学习笔记八—— RESTFul案例-实现增删改查

kxttmx

2024-05-10 帮助1人

08、RESTFul案例

8.1、准备工作

和传统 CRUD 一样，实现对员工信息的增删改查。

1、新建module --> springMVC-rest

2、配置xml文件

【web.xml】

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
         version="4.0">
    <!--配置编码过滤器-->
    <filter>
        <filter-name>CharacterEncodingFilter</filter-name>
        <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
        <init-param>
            <param-name>encoding</param-name>
            <param-value>UTF-8</param-value>
        </init-param>
        <init-param>
            <param-name>forceResponseEncoding</param-name>
            <param-value>true</param-value>
        </init-param>
    </filter>
    <filter-mapping>
        <filter-name>CharacterEncodingFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

    <!--配置处理请求方式put和delete的HiddenHttpMethodFilter过滤器-->
    <filter>
        <filter-name>HiddenHttpMethodFilter</filter-name>
        <filter-class>org.springframework.web.filter.HiddenHttpMethodFilter</filter-class>
    </filter>
    <filter-mapping>
        <filter-name>HiddenHttpMethodFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

    <!--配置SpringMVC的前端控制器DispatcherServlet-->
    <servlet>
        <servlet-name>DispatcherServlet</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>classpath:springMVC.xml</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>DispatcherServlet</servlet-name>
        <url-pattern>/*</url-pattern>
    </servlet-mapping>
</web-app>

【springMVC.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:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd">

    <!--扫描组件-->
    <context:component-scan base-package="com.ssm.mvc"></context:component-scan>


    <!--配置Thymeleaf视图解析器-->
    <bean id="viewResolver" class="org.thymeleaf.spring5.view.ThymeleafViewResolver">
        <property name="order" value="1"/>
        <property name="characterEncoding" value="UTF-8"/>
        <property name="templateEngine">
            <bean class="org.thymeleaf.spring5.SpringTemplateEngine">
                <property name="templateResolver">
                    <bean class="org.thymeleaf.spring5.templateresolver.SpringResourceTemplateResolver">
                        <!-- 视图前缀 -->
                        <property name="prefix" value="/WEB-INF/templates/"/>
                        <!-- 视图后缀 -->
                        <property name="suffix" value=".html"/>
                        <property name="templateMode" value="HTML5"/>
                        <property name="characterEncoding" value="UTF-8" />
                    </bean>
                </property>
            </bean>
        </property>
    </bean>
</beans>

3、准备实体类

【Employee.java】

public class Employee {
    private Integer id;
    private String lastName;
    private String email;
    private Integer gender;//1:male 0:female

    public Employee() {
    }

    public Employee(Integer id, String lastName, String email, Integer gender) {
        this.id = id;
        this.lastName = lastName;
        this.email = email;
        this.gender = gender;
    }

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getLastName() {
        return lastName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public Integer getGender() {
        return gender;
    }

    public void setGender(Integer gender) {
        this.gender = gender;
    }
}

4、准备dao模拟数据

【EmployeeDAO.java】

@Repository
public class EmployeeDAO {
    private static Map<Integer, Employee> employees = null;

    static {
        employees = new HashMap<Integer, Employee>();
        employees.put(1001,new Employee(1001,"E-AA","aa@163.com",1));
        employees.put(1002,new Employee(1002,"E-BB","bb@163.com",1));
        employees.put(1003,new Employee(1003,"E-CC","cc@163.com",0));
        employees.put(1004,new Employee(1004,"E-DD","dd@163.com",0));
        employees.put(1005,new Employee(1005,"E-EE","ee@163.com",1));
    }

    private static Integer initId = 1006;

    public void save(Employee employee) {
        if (employee.getId() == null) {
            employee.setId(initId  );
        }
        employees.put(employee.getId(), employee);
    }

    public Collection<Employee> getAll() {
        return employees.values();
    }

    public Employee get(Integer id) {
        return employees.get(id);
    }

    public void delete(Integer id) {
        employees.remove(id);
    }
}

8.2、功能清单

功能	URL地址	请求方式
访问首页	/	GET
查询全部数据	/employee	GET
删除	/employee/2	DELETE
跳转到添加数据页面	/toAdd	GET
执行保存	/employee	POST
跳转到更新数据页面	/employee/2	GET
执行更新	/employee	PUT

8.3、功能实现

8.3.1、访问页面

1、配置view-controller

【springMVC.xml】

<!--配置视图控制器-->
<mvc:view-controller path="/" view-name="index"></mvc:view-controller>

<!--开启mvc注解驱动-->
<mvc:annotation-driven/>

2、创建页面

【index.html】

<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head>
    <meta charset="UTF-8">
    <title>首页</title>
</head>
<body>
<h1>首页</h1>
<a th:href="@{/employee}">查看员工信息</a>
</body>
</html>

8.3.2、查询所有员工数据

1、控制器方法

【EmployeeController.java】

@Controller
public class EmployeeController {

    @Autowired
    public EmployeeDAO employeeDAO;

    //@GetMapping("/employee")
    @RequestMapping(value = "employee", method = RequestMethod.GET)
    public String getAllEmployee(Model model){
        Collection<Employee> employeeList = employeeDAO.getAll();
        model.addAttribute("employeeList", employeeList);

        return "employee_list";
    }
}

【employee_list.html】

<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head>
    <meta charset="UTF-8">
    <title>Employee_Info</title>
</head>
<body>
    <table border="1" cellspacing="0" cellpadding="0" style="text-align: center">
        <tr>
            <th colspan="5">Employee Info</th>
        </tr>
        <tr>
            <th>id</th>
            <th>lastName</th>
            <th>email</th>
            <th>gender</th>
            <th>options</th>
        </tr>
        <tr th:each="employee:${employeeList}">
            <td th:text="${employee.id}"></td>
            <td th:text="${employee.lastName}"></td>
            <td th:text="${employee.email}"></td>
            <td th:text="${employee.gender}"></td>
            <td>
                <a href="">delete</a>&nbsp;
                <a href="">update</a>
            </td>
        </tr>
    </table>
</body>
</html>

3.3.3、删除

1、创建处理delete请求方式的表单

<!--超链接只能发送get请求，而我们需要发送delete请求，
            则需要通过HiddenHttpMethodFilter过滤器，而此过滤器需要发送post请求以及"_method"参数
            需要创建表单实现-->
<!--action未赋值或未写，默认为提交到当前页面-->
<form id="deleteForm" method="post">
    <input type="hidden" name="_method" value="delete">
</form>

2、删除超链接绑定点击事件

（1）引入vue.js

<script type="text/javascript" th:src="@{/static/js/vue.js}"></script>

（2）删除超链接

<a @click="deleteEmployee" th:href="@{'/employee/' ${employee.id}}">delete</a>&nbsp;

（3）通过vue处理点击事件

<script type="text/javascript">
    var vue = new Vue({
        el:"#dataTable",
        methods:{
            deleteEmployee:function (event) {
                //根据id获取表单元素
                var deleteForm = document.getElementById("deleteForm");
                //将触发点击事件的超链接的href属性赋值给表单的action
                deleteForm.action = event.target.href;
                //提交表单
                deleteForm.submit();
                //取消超链接的默认行为
                event.preventDefault();
            }
        }
    });
</script>

3、执行删除

【EmployeeController.java】

@Controller
public class EmployeeController {

    @Autowired
    public EmployeeDAO employeeDAO;

    @RequestMapping(value = "/employee/{id}",method = RequestMethod.DELETE)
    public String deleteEmployee(@PathVariable("id") Integer id) {
        System.out.println(id);
        employeeDAO.delete(id);
        return "redirect:/employee";
    }
}

4、开放对静态资源的访问

【springMVC.xml】

<!--开放对静态资源的访问-->
<mvc:default-servlet-handler/>

3.3.4、添加

1、配置view-controller

【springMVC.xml】

<mvc:view-controller path="/toAdd" view-name="employee_add"></mvc:view-controller>

2、创建添加页面

【employee_add.html】

<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head>
    <meta charset="UTF-8">
    <title>add employee</title>
</head>
<body>
    <form th:action="@{/employee}" method="post">
        lastName:<input type="text" name="lastName"><br>
        email:<input type="text" name="email"><br>
        gender:<input type="radio" name="gender" value="1">male
        <input type="radio" name="gender" value="0">female<br>
        <input type="submit" value="add"><br>
    </form>
</body>
</html>

3、执行添加

【EmployeeController.java】

@Controller
public class EmployeeController {

    @Autowired
    public EmployeeDAO employeeDAO;

    @RequestMapping(value = "/employee",method = RequestMethod.POST)
    public String addEmployee(Employee employee) {
        employeeDAO.save(employee);
        return "redirect:/employee";
    }
}

3.3.5、修改

1、修改超链接

<a th:href="@{'/employee/' ${employee.id}}">update</a>

2、跳转到修改页面

【EmployeeController.java】

@RequestMapping(value = "/employee/{id}",method = RequestMethod.GET)
public String getEmployeeById(@PathVariable("id") Integer id, Model model) {
    Employee employee = employeeDAO.get(id);
    model.addAttribute("employee", employee);
    return "employee_update";
}

3、创建修改页面

【employee_update.html】

<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head>
    <meta charset="UTF-8">
    <title>update employee</title>
</head>
<body>
    <form th:action="@{/employee}" method="post">
        <input type="hidden" name="_method" value="put">
        <input type="hidden" name="id" th:value="${employee.id}">
        lastName:<input type="text" name="lastName" th:value="${employee.lastName}"><br>
        email:<input type="text" name="email" th:value="${employee.email}"><br>
        gender:<input type="radio" name="gender" value="1" th:field="${employee.gender}">male
        <input type="radio" name="gender" value="0" th:field="${employee.gender}">female<br>
        <input type="submit" value="update"><br>
    </form>
</body>
</html>

4、执行更新

【EmployeeController.java】

@Controller
public class EmployeeController {

    @Autowired
    public EmployeeDAO employeeDAO;

    @RequestMapping(value = "/employee", method = RequestMethod.PUT)
    public String updateEmployee(Employee employee) {
        employeeDAO.save(employee);
        return "redirect:/employee";
    }
}

这篇好文章是转载于：学新通技术网

SpringMVC学习笔记八—— RESTFul案例-实现增删改查

08、RESTFul案例

8.1、准备工作

8.2、功能清单

8.3、功能实现

8.3.1、访问页面

8.3.2、查询所有员工数据

3.3.3、删除

3.3.4、添加

3.3.5、修改

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