springmvc实例之显示雇员相关信息（一）

Julywhj

2020-01-11

一、新建一个Dynamic Web Project（一直Next到最后，勾选Generate...，否则不会有web.xml文件）。

二、在lib文件夹中加入相应jar包

springmvc实例之显示雇员相关信息（一）

三、在web.xml中配置

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
    <!-- The front controller of this Spring Web application, responsible for handling all application requests -->
    <servlet>
        <servlet-name>springDispatcherServlet</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>

    <!-- Map all requests to the DispatcherServlet for handling -->
    <servlet-mapping>
        <servlet-name>springDispatcherServlet</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>
    
    <!-- 配置 HiddenHttpMethodFilter: 把 POST 请求转为 DELETE、PUT 请求 -->
    <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>
    
</web-app>

四、在src目录下新建一个springmvc.xml配置文件，并配置

<?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 http://www.springframework.org/schema/context/spring-context-4.0.xsd">
    
    <!-- 配置自动扫描的包 -->
    <context:component-scan base-package="com.gong.springmvc"></context:component-scan>
    
    <!-- 配置视图解析器，将逻辑视图转换成物理视图 -->
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/views/"></property>
        <property name="suffix" value=".jsp"></property>
    </bean>
</beans>

五、在src目录下新建com.gong.springmvc.curd.entties、com.gong.springmvc.curd.dao、com.gong.springmvc.curd.handlers包

1.在com.gong.springmvc.curd.entties中新建Departmen.java和Employee.java

Department.java

package com.gong.springmvc.crud.entities;

public class Department {

    private Integer id;
    private String departmentName;

    public Department() {
        // TODO Auto-generated constructor stub
    }
    
    public Department(int i, String string) {
        this.id = i;
        this.departmentName = string;
    }

    public Integer getId() {
        return id;
    }

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

    public String getDepartmentName() {
        return departmentName;
    }

    public void setDepartmentName(String departmentName) {
        this.departmentName = departmentName;
    }

    @Override
    public String toString() {
        return "Department [id=" + id + ", departmentName=" + departmentName
                + "]";
    }
    
}

Employee.java

package com.gong.springmvc.crud.entities;

import java.util.Date;public class Employee {

    private Integer id;

    private String lastName;

    private String email;
    //1 male, 0 female
    private Integer gender;
    
    private Department department;
    
    private Date birth;
    
    private Float salary;

    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;
    }

    public Department getDepartment() {
        return department;
    }

    public void setDepartment(Department department) {
        this.department = department;
    }

    public Date getBirth() {
        return birth;
    }

    public void setBirth(Date birth) {
        this.birth = birth;
    }

    public Float getSalary() {
        return salary;
    }

    public void setSalary(Float salary) {
        this.salary = salary;
    }

    @Override
    public String toString() {
        return "Employee [id=" + id + ", lastName=" + lastName + ", email="
                + email + ", gender=" + gender + ", department=" + department
                + ", birth=" + birth + ", salary=" + salary + "]";
    }

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

    public Employee() {
        // TODO Auto-generated constructor stub
    }
}

2.在com.gong.springmvc.curd.dao中新建DepartmentDao.java和EmployeeDao.java

DepartmentDao.java

package com.gong.springmvc.crud.dao;

import java.util.Collection;
import java.util.HashMap;
import java.util.Map;

import org.springframework.stereotype.Repository;

import com.gong.springmvc.crud.entities.Department;

@Repository
public class DepartmentDao {

    private static Map<Integer, Department> departments = null;
    
    static{
        departments = new HashMap<Integer, Department>();
        
        departments.put(101, new Department(101, "D-AA"));
        departments.put(102, new Department(102, "D-BB"));
        departments.put(103, new Department(103, "D-CC"));
        departments.put(104, new Department(104, "D-DD"));
        departments.put(105, new Department(105, "D-EE"));
    }
    
    public Collection<Department> getDepartments(){
        return departments.values();
    }
    
    public Department getDepartment(Integer id){
        return departments.get(id);
    }
    
}

EmployeeDao.java

package com.gong.springmvc.crud.dao;

import java.util.Collection;
import java.util.HashMap;
import java.util.Map;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Repository;

import com.gong.springmvc.crud.entities.Department;
import com.gong.springmvc.crud.entities.Employee;

@Repository
public class EmployeeDao {

    private static Map<Integer, Employee> employees = null;
    
    @Autowired
    private DepartmentDao departmentDao;
    
    static{
        employees = new HashMap<Integer, Employee>();

        employees.put(1001, new Employee(1001, "E-AA", "", 1, new Department(101, "D-AA")));
        employees.put(1002, new Employee(1002, "E-BB", "", 1, new Department(102, "D-BB")));
        employees.put(1003, new Employee(1003, "E-CC", "", 0, new Department(103, "D-CC")));
        employees.put(1004, new Employee(1004, "E-DD", "", 0, new Department(104, "D-DD")));
        employees.put(1005, new Employee(1005, "E-EE", "", 1, new Department(105, "D-EE")));
    }
    
    private static Integer initId = 1006;
    
    public void save(Employee employee){
        if(employee.getId() == null){
            employee.setId(initId++);
        }
        
        employee.setDepartment(departmentDao.getDepartment(employee.getDepartment().getId()));
        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);
    }
}

只是为了理解springmvc，就直接模拟数据库中的数据。

3.在com,gong.springmvc.curd.handlers中新建一个EmployeeHandler.java

EmployeeHandler.java

package com.gong.springmvc.crud.handlers;

import java.util.Map;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;

import com.gong.springmvc.crud.dao.DepartmentDao;
import com.gong.springmvc.crud.dao.EmployeeDao;

@Controller
public class EmployeeHandler {
    @Autowired
    private EmployeeDao employeeDao;
    @Autowired
    private DepartmentDao departmentDao;
    
    @RequestMapping("/emps")
    public String list(Map<String,Object> map) {
        map.put("employees", employeeDao.getAll());
        return "list";
    }
}

六、jsp页面设置

1.在WebCont下新建一个index.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
    <a href="emps">testList</a>
</body>
</html>

该jsp中的href="emps"对应着EmployeeHandler.java中的list方法，该方法最后返回/WEB-INF/views/list.jsp。

在WEB-INF下新建一个views文件夹，在该文件夹下新建一个list.jsp

list.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
    <c:if test="${empty requestScope.employees }">
        没有任何员工信息.
    </c:if>
    <c:if test="${!empty requestScope.employees }">
        <table border="1" cellpadding="10" cellspacing="0">
            <tr>
                <th>ID</th>
                <th>LastName</th>
                <th>Email</th>
                <th>Gender</th>
                <th>Department</th>
                <th>Edit</th>
                <th>Delete</th>
            </tr>
            
            <c:forEach items="${requestScope.employees }" var="emp">
                <tr>
                    <td>${emp.id }</td>
                    <td>${emp.lastName }</td>
                    <td>${emp.email }</td>
                    <td>${emp.gender == 0 ? ‘Female‘ : ‘Male‘ }</td>
                    <td>${emp.department.departmentName }</td>
                    <td><a href="emp/${emp.id}">Edit</a></td>
                    <td><a class="delete" href="emp/${emp.id}">Delete</a></td>
                </tr>
            </c:forEach>
        </table>
    </c:if>
    <br><br>
</body>
</html>

七、启动服务器之后

springmvc实例之显示雇员相关信息（一）