SpringMVC + Spring + SpringDataJPA 整合

Posted 2023-01-11 普通网友

tags:

篇首语：本文由小常识网(cha138.com)小编为大家整理，主要介绍了SpringMVC + Spring + SpringDataJPA 整合相关的知识，希望对你有一定的参考价值。

涉及技术： –1.SpringMVC、Spring、SpringData\\JPA整合完成CRUD、翻页 –2.基于Restful风格 –3.使用JPA二级缓存 –4.使用@ResponseBody注解完成Ajax.
完成分页操作
•Dao 层： –不带查询查询条件的分页，所以可以直接调用 PagingAndSortingRepository# findAll(Pageable pageable) 返回 Page 对象。 •Service 层： –没有业务逻辑 –把 Controller 传入的 pageNo 和pageSize 封装为Pageable 对象。注意：Pageable 的pageNo 是从0 开始的 –调用 Dao层的方法即可。 •Controller 层： –获取 pageNo，并对 pageNo 进行校验 –调用 Service方法返回 Page对象 –把 Page 对象放入到request 中 –转发页面 JSP 页面：使用JSTL 来显示页面

添加操作：显示页面 & 使用 JPA 二级缓存
•Dao 层： –查询所有的 Department –且需要使用JPA 的二级缓存？ •Service 层：调用 Dao层的方法，获取所有的 Department，返回即可 •Controller 层： –调用Service 层，获取所有的 Department，并放入到 request 中 –创建一个新的Employee 对象，放入到 request 中。且其键和表单的 modelAttribute 属性值一致。 –转发页面 •JSP 页面： –需要使用 SpringMVC 的表单标签来显示表单页面 –注意：form:form 标签必须设置一个modelAttribute 属性，以从request 中获取对应的 bean，要求该bean 的属性和表单字段是一一对应的。
Ajax 验证用户名可用性 •Dao 层：新建一个方法：根据lastName 查询对应的Employee，若存在返回 Employee 对象，若不存在则返回 null •Service 层：直接调用 Dao 方法返回结果即可。 •Controller 层： –获取请求参数 –调用 Service层验证 lastName 对应的Employee 是否存在 –若存在则返回“1”，若不存在则返回“0”。需要使用 @ResponseBody 注解 •JSP 页面：使用jQuery 完成Ajax 的发送，和结果的响应。
完成添加
•Dao 层：不需要定义任何方法，直接使用JpaRepository 或其父接口提供的save 方法即可 •Service 层：需要调用 Dao 层的方法。注意：需要设置createTime 属性 •Controller 层：调用 Service层的方法，重定向到显示所有员工的页面 •注意：如何把页面上输入的字符串转为Date 类型。使用@DateTimeFormat 注解!
表单回显
•SpringMVC 表单回显的原理： –实际上表单的回显是由 SpringMVC 的form 标签完成的 –在 Handler 方法中，向request 中添加一个属性。键：SpringMVC form:form 标签modelAttribute 属性值，值：包含了回显信息的一个bean 对象 •URL：/emp/id，method：GET •Dao 层：直接调用方法，根据id 来获取对应的bean •Service 层：调用 Dao层的方法，返回 bean 对象 •Controller 层： –获取 id –调用 Service方法，得到 bean 的对象 –获取全部的 Department，并放入到 request 中。 –把 bean 对象放入到request 中，键为：form:form 标签的modelAttribute 属性值 –转发页面
修改状态下 Ajax 验证用户名可用性
•和添加状态下 Ajax验证的区别：若修改后当前的lastName，则不应该再发送任何Ajax请求，而直接alert：用户名可用。 •JSP 页面：修改JS的Ajax请求逻辑：若修改回之前的lastName则不发送任何请求，直接弹出“用户名可用”
完成修改
•URL：emp/id，method：PUT •Dao 层：继续使用saveAndFlush 方法即可 •Service 层： –不需要设置 createTime 属性 –判定添加和修改的标准：传入的 bean 的id 是否为null •Cotroller 层： –新建 @ModelAttribute 注解修饰的方法，在其中利用id 获取对应的bean，并把该bean 放入到map 中，键为：Employee 类名第一个字母小写 –在 @ModelAttribute 方法中，把关联的department 置为 null –调用 Service 的方法进行更新 –重定向到：/emps •JSP 页面：id 和_method 加入到隐藏域中。
完成删除
•URL：emp/id、method：DELETE •Dao 层：直接使用 SpringData 已经自带的delete 方法即可 •Service层：直接调用 Dao 方法即可 •Controller层： –直接调用 Service 方法 –重定向到 /emps •JSP 页面： –使用 JSconfirm：确定要删除xx 的信息吗 –把超链接的GET 请求转为POST 请求，且携带_method=DELETE 的请求参数
web.xml

<?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_2_5.xsd" id="WebApp_ID" version="2.5">

	<!-- 配置启动 IOC 容器的 Listener -->
	<context-param>
		<param-name>contextConfigLocation</param-name>
		<param-value>classpath:applicationContext.xml</param-value>
	</context-param>

	<listener>
		<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
	</listener>
	
	<!-- 配置字符编码过滤器 -->
	<!-- 字符编码过滤器必须配置在所有过滤器的最前面! -->
	<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>
	</filter>
	
	<filter-mapping>
		<filter-name>CharacterEncodingFilter</filter-name>
		<url-pattern>/*</url-pattern>
	</filter-mapping>
	
	<!-- 配置可以把 POST 请求转为 PUT、DELETE 请求的 Filter -->
	<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 OpenEntityManagerInViewFilter. 可以解决懒加载异常的问题 -->
	<filter>
		<filter-name>OpenEntityManagerInViewFilter</filter-name>
		<filter-class>org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter</filter-class>
	</filter>
	
	<filter-mapping>
		<filter-name>OpenEntityManagerInViewFilter</filter-name>
		<url-pattern>/*</url-pattern>
	</filter-mapping>
	
	<!-- 配置 SpringMVC 的 DispatcherServlet -->
	<servlet>
		<servlet-name>springDispatcherServlet</servlet-name>
		<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
		<load-on-startup>1</load-on-startup>
	</servlet>

	<servlet-mapping>
		<servlet-name>springDispatcherServlet</servlet-name>
		<url-pattern>/</url-pattern>
	</servlet-mapping>

</web-app>

springDispatcherServlet-servlet.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"
	xmlns:mvc="http://www.springframework.org/schema/mvc"
	xsi:schemaLocation="http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd
		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.atguigu.sssp" use-default-filters="false">
		<context:include-filter type="annotation" expression="org.springframework.stereotype.Controller"/>
		<context:include-filter type="annotation" expression="org.springframework.web.bind.annotation.ControllerAdvice"/>
	</context:component-scan>
	
	<!-- 配置视图解析器 -->
	<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
		<property name="prefix" value="/WEB-INF/views/"></property>
		<property name="suffix" value=".jsp"></property>
	</bean>

	<mvc:default-servlet-handler/>
	<mvc:annotation-driven></mvc:annotation-driven>

</beans>

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">List All Employees</a>
	<br><br>
	
	<a href="emp">Add New Employee</a>
	
</body>
</html>

views/emp
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" %>
<%@ taglib prefix="fmt" uri="http://java.sun.com/jsp/jstl/fmt" %>
    
<!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>
<script type="text/javascript" src="$pageContext.request.contextPath /scripts/jquery-1.9.1.min.js"></script>
<script type="text/javascript">
	$(function()
		$(".delete").click(function()
			var label = $(this).next(":hidden").val();
			var flag = confirm("确定要删除" + label + "的信息吗?");
			if(flag)
				var url = $(this).attr("href");
				
				$("#_form").attr("action", url);
				$("#_method").val("DELETE");
				$("#_form").submit();
			
			
			return false;
		);
	)
</script>
</head>
<body>

	<form action="" method="POST" id="_form">
		<input type="hidden" id="_method" name="_method"/>
	</form>
	
	<c:if test="$page == null || page.numberOfElements == 0 ">
		没有任何记录. 
	</c:if>
	<c:if test="$page != null && page.numberOfElements > 0 ">
		<table border="1" cellpadding="10" cellspacing="0">
			<tr>
				<th>ID</th>
				<th>LastName</th>
				
				<th>Email</th>
				<th>Birth</th>
				
				<th>CreateTime</th>
				<th>Department</th>
				
				<th>Edit</th>
				<th>Delete</th>
			</tr>
			
			<c:forEach items="$page.content " var="emp">
				<tr>
					<td>$emp.id </td>
					<td>$emp.lastName </td>
					
					<td>$emp.email </td>
					<td>
						<fmt:formatDate value="$emp.birth " pattern="yyyy-MM-dd"/>
					</td>
					
					<td>
						<fmt:formatDate value="$emp.createTime " pattern="yyyy-MM-dd hh:mm:ss"/>
					</td>
					<td>$emp.department.departmentName </td>
					
					<td><a href="$pageContext.request.contextPath /emp/$emp.id">Edit</a></td>
					<td>
						<a href="$pageContext.request.contextPath /emp/$emp.id" class="delete">Delete</a>
						<input type="hidden" value="$emp.lastName "/>
					</td>
				</tr>
			</c:forEach>
			
			<tr>
				<td colspan="8">
					共 $page.totalElements  条记录
					共 $page.totalPages  页
					当前 $page.number + 1  页
					<a href="?pageNo=$page.number + 1 - 1 ">上一页</a>
					<a href="?pageNo=$page.number + 1 + 1 ">下一页</a>
				</td>
			</tr>
			
		</table>
	</c:if>
	
</body>
</html>

input.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<%@ taglib prefix="form" uri="http://www.springframework.org/tags/form" %>
<%@ 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>
<script type="text/javascript" src="$pageContext.request.contextPath /scripts/jquery-1.9.1.min.js"></script>
<script type="text/javascript">
	$(function()
		$("#lastName").change(function()
			var val = $(this).val();
			val = $.trim(val);
			$(this).val(val);
			
			//若修改的 lastName 和之前的 lastName 一致, 则不发送 Ajax 请求, 直接 alert:lastName 可用!
			var _oldLastName = $("#_oldLastName").val();
			_oldLastName = $.trim(_oldLastName);
			if(_oldLastName != null && _oldLastName != "" && _oldLastName == val)
				alert("lastName 可用!");
				return;
			
			
			var url = "$pageContext.request.contextPath /ajaxValidateLastName";
			var args = "lastName":val,"date":new Date();
			
			$.post(url, args, function(data)
				if(data == "0")
					alert("lastName 可用!");
				else if(data == "1")
					alert("lastName 不可用!");
				else
					alert("网络或程序出错. ");
				
			);
		);
	)
</script>
</head>
<body>
	
	<c:set value="$pageContext.request.contextPath /emp" var="url"></c:set>
	<c:if test="$employee.id != null ">
		<c:set value="$pageContext.request.contextPath /emp/$employee.id" var="url"></c:set>
	</c:if>
	
	<form:form action="$url " method="POST" modelAttribute="employee">
		
		<c:if test="$employee.id != null ">
			<input type="hidden" id="_oldLastName" value="$employee.lastName "/>
			<form:hidden path="id"/>
			<input type="hidden" name="_method" value="PUT"/>
		</c:if>
	
		LastName: <form:input path="lastName" id="lastName"/>
		<br>
		Email: <form:input path="email"/>
		<br>
		Birth: <form:input path="birth"/>
		<br>
		Department: 
		<form:select path="department.id" items="$departments " 
			itemLabel="departmentName" itemValue="id"></form:select>
		<br>
		<input type="submit" value="Submit"/>
		
	</form:form>
		
</body>
</html>

db.properties

jdbc.user=root
jdbc.password=1230
jdbc.driverClass=com.mysql.jdbc.Driver
jdbc.jdbcUrl=jdbc:mysql:///spring

applicationContext.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"
	xmlns:tx="http://www.springframework.org/schema/tx"
	xmlns:jpa="http://www.springframework.org/schema/data/jpa"
	xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
		http://www.springframework.org/schema/data/jpa http://www.springframework.org/schema/data/jpa/spring-jpa-1.3.xsd
		http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.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.atguigu.sssp">
		<context:exclude-filter type="annotation" expression="org.springframework.stereotype.Controller"/>
		<context:exclude-filter type="annotation" expression="org.springframework.web.bind.annotation.ControllerAdvice"/>
	</context:component-scan>
	
	<!-- 配置数据源 -->
	<context:property-placeholder location="classpath:db.properties"/>

	<bean id="dataSource"
		class="com.mchange.v2.c3p0.ComboPooledDataSource">
		<property name="user" value="$jdbc.user"></property>	
		<property name="password" value="$jdbc.password"></property>	
		<property name="driverClass" value="$jdbc.driverClass"></property>	
		<property name="jdbcUrl" value="$jdbc.jdbcUrl"></property>	
		
		<!-- 配置其他属性 -->
	</bean>
	
	<!-- 配置 JPA 的 EntityManagerFactory -->
	<bean id="entityManagerFactory"
		class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
		<property name="dataSource" ref="dataSource"></property>
		<property name="jpaVendorAdapter">
			<bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter"></bean>
		</property>	
		<property name="packagesToScan" value="com.atguigu.sssp"></property>
		<property name="jpaProperties">
			<props>
				<prop key="hibernate.ejb.naming_strategy">org.hibernate.cfg.ImprovedNamingStrategy</prop>
				<prop key="hibernate.hbm2ddl.auto">update</prop>
				<prop key="hibernate.show_sql">true</prop>
				<prop key="hibernate.format_sql">true</prop>
				<prop key="hibernate.dialect">org.hibernate.dialect.MySQL5InnoDBDialect</prop>
				
				<prop key="hibernate.cache.use_second_level_cache">true</prop>
				<prop key="hibernate.cache.region.factory_class">org.hibernate.cache.ehcache.EhCacheRegionFactory</prop>
				<prop key="hibernate.cache.use_query_cache">true</prop>
			</props>
		</property>
		<property name="sharedCacheMode" value="ENABLE_SELECTIVE"></property>
	</bean>
	
	<!-- 配置事务 -->
	<bean id="transactionManager"
		class="org.springframework.orm.jpa.JpaTransactionManager">
		<property name="entityManagerFactory" ref="entityManagerFactory"></property>	
	</bean>
	
	<!-- 配置支持基于注解的事务 -->
	<tx:annotation-driven transaction-manager="transactionManager"/>
	
	<!-- 配置 SpringData -->
	<jpa:repositories base-package="com.atguigu.sssp"
		entity-manager-factory-ref="entityManagerFactory"></jpa:repositories>
	
</beans>

entity
Department.java

package com.atguigu.sssp.entity;

import javax.persistence.Cacheable;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.Table;

@Cacheable
@Table(name="SSSP_DEPARTMENTS")
@Entity
public class Department 

	private Integer id;
	private String departmentName;

	@GeneratedValue
	@Id
	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;

Employee.java

package com.atguigu.sssp.entity;

import java.util.Date;

import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;
import javax.persistence.Table;
import javax.persistence.Temporal;
import javax.persistence.TemporalType;

import org.springframework.format.annotation.DateTimeFormat;

@Table(name="SSSP_EMPLOYEES")
@Entity
public class Employee 
	
	private Integer id;
	private String lastName;
	
	private String email;
	@DateTimeFormat(pattern="yyyy-MM-dd")
	private Date birth;
	
	private Date createTime;
	
	private Department department;

	@GeneratedValue
	@Id
	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;
	

	@Temporal(TemporalType.DATE)
	public Date getBirth() 
		return birth;
	

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

	@Temporal(TemporalType.TIMESTAMP)
	public Date getCreateTime() 
		return createTime;
	

	public void setCreateTime(Date createTime) 
		this.createTime = createTime;
	

	@JoinColumn(name="DEPARTMENT_ID")
	@ManyToOne(fetch=FetchType.LAZY)
	public Department getDepartment() 
		return department;
	

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

repository
DepartmentRepository.java

package com.atguigu.sssp.repository;

import java.util.List;

import javax.persistence.QueryHint;

import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.Query;
import org.springframework.data.jpa.repository.QueryHints;

import com.atguigu.sssp.entity.Department;

public interface DepartmentRepository extends JpaRepository<Department, Integer>

	@QueryHints(@QueryHint(name=org.hibernate.ejb.QueryHints.HINT_CACHEABLE,value="true"))
	@Query("FROM Department d")
	List<Department> getAll();

EmployeeRepository.java

package com.atguigu.sssp.repository;

import org.springframework.data.jpa.repository.JpaRepository;

import com.atguigu.sssp.entity.Employee;

public interface EmployeeRepository extends JpaRepository<Employee, Integer> 

	Employee getByLastName(String lastName);

service
DepartmentService.java

package com.atguigu.sssp.service;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import com.atguigu.sssp.entity.Department;
import com.atguigu.sssp.repository.DepartmentRepository;

@Service
public class DepartmentService 

	@Autowired
	private DepartmentRepository departmentRepository;
	
	@Transactional(readOnly=true)
	public List<Department> getAll()
		return departmentRepository.getAll();

EmployeeService.java

package com.atguigu.sssp.service;

import java.util.Date;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.PageRequest;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import com.atguigu.sssp.entity.Employee;
import com.atguigu.sssp.repository.EmployeeRepository;

@Service
public class EmployeeService 

	@Autowired
	private EmployeeRepository employeeRepository;
	
	@Transactional
	public void delete(Integer id)
		employeeRepository.delete(id);
	
	
	@Transactional(readOnly=true)
	public Employee get(Integer id)
		return employeeRepository.findOne(id);
	
	
	@Transactional
	public void save(Employee employee)
		if(employee.getId() == null)
			employee.setCreateTime(new Date());
		
		employeeRepository.saveAndFlush(employee);
	
	
	@Transactional(readOnly=true)
	public Employee getByLastName(String lastName)
		return employeeRepository.getByLastName(lastName);
	
	
	@Transactional(readOnly=true)
	public Page<Employee> getPage(int pageNo, int pageSize)
		PageRequest pageable = new PageRequest(pageNo - 1, pageSize);
		return employeeRepository.findAll(pageable);

handler
EmployeeHandler.java

package com.atguigu.sssp.handler;

import java.util.Map;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.domain.Page;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;

import com.atguigu.sssp.entity.Employee;
import com.atguigu.sssp.service.DepartmentService;
import com.atguigu.sssp.service.EmployeeService;

@Controller
public class EmployeeHandler 

	@Autowired
	private EmployeeService employeeService;
	
	@Autowired
	private DepartmentService departmentService;

	@RequestMapping(value="/emp/id",method=RequestMethod.DELETE)
	public String delete(@PathVariable("id") Integer id)
		employeeService.delete(id);
		return "redirect:/emps";
	
	
	@ModelAttribute
	public void getEmployee(@RequestParam(value="id",required=false) Integer id,
			Map<String, Object> map)
		if(id != null)
			Employee employee = employeeService.get(id);
			employee.setDepartment(null);
			map.put("employee", employee);
		
	
	
	@RequestMapping(value="/emp/id",method=RequestMethod.PUT)
	public String update(Employee employee)
		employeeService.save(employee);
		return "redirect:/emps";
	
	
	@RequestMapping(value="/emp/id", method=RequestMethod.GET)
	public String input(@PathVariable("id") Integer id, Map<String, Object> map)
		Employee employee = employeeService.get(id);
		map.put("employee", employee);
		map.put("departments", departmentService.getAll());
		return "emp/input";
	
	
	@RequestMapping(value="/emp",method=RequestMethod.POST)
	public String save(Employee employee)
		employeeService.save(employee);
		return "redirect:/emps";
	
	
	@ResponseBody
	@RequestMapping(value="/ajaxValidateLastName",method=RequestMethod.POST)
	public String validateLastName(@RequestParam(value="lastName",required=true) String lastName)
		Employee employee = employeeService.getByLastName(lastName);
		if(employee == null)
			return "0";
		else
			return "1";
		
	
	
	@RequestMapping(value="/emp",method=RequestMethod.GET)
	public String input(Map<String,Object> map)
		map.put("departments", departmentService.getAll());
		map.put("employee", new Employee());
		return "emp/input";
	
	
	@RequestMapping("/emps")
	public String list(@RequestParam(value="pageNo", required=false, defaultValue="1") String pageNoStr, 
			Map<String, Object> map)
		int pageNo = 1;
		
		try 
			//对 pageNo 的校验
			pageNo = Integer.parseInt(pageNoStr);
			if(pageNo < 1)
				pageNo = 1;
			
		 catch (Exception e) 
		
		Page<Employee> page = employeeService.getPage(pageNo, 5);
		map.put("page", page);
		
		return "emp/list";

以上是关于SpringMVC + Spring + SpringDataJPA 整合的主要内容，如果未能解决你的问题，请参考以下文章

ServletContext 和 Spring MVC

一Spring MVC基础

第八篇.SpringMVC入门学习

Spring MVC学习—ViewSolvsolver视图解析器的详细介绍与使用案例

Spring Boot中实现定时任务的两种方式

springsource是啥