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Spring MVC分页示例
分页用于在不同部分显示大量记录。在这种情况下，我们将在一页中显示10、20或50条记录。对于其余记录，我们提供链接。
我们可以在Spring MVC中简单地创建分页示例。在此分页示例中，我们使用MySQL数据库来获取记录。
创建表或导入SQL文件
在这里，我们已经在"测试"数据库中创建了" emp"表。 emp表具有三个字段: ID，名称和薪水。创建表并手动插入记录，或导入我们的SQL文件。
Spring MVC分页示例
1、将依赖项添加到pom.xml文件。
pom.xml
示例
<!-- https://mvnrepository.com/artifact/org.springframework/spring-webmvc --> <dependency><groupId>org.springframework</groupId><artifactId>spring-webmvc</artifactId><version>5.1.1.RELEASE</version> </dependency> <!-- https://mvnrepository.com/artifact/org.apache.tomcat/tomcat-jasper --> <dependency><groupId>org.apache.tomcat</groupId><artifactId>tomcat-jasper</artifactId><version>9.0.12</version> </dependency><!-- https://mvnrepository.com/artifact/javax.servlet/javax.servlet-api --> <dependency> <groupId>javax.servlet</groupId> <artifactId>servlet-api</artifactId> <version>3.0-alpha-1</version> </dependency> <!-- https://mvnrepository.com/artifact/javax.servlet/jstl --> <dependency><groupId>javax.servlet</groupId><artifactId>jstl</artifactId><version>1.2</version> </dependency><!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java --> <dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId><version>8.0.11</version> </dependency><!-- https://mvnrepository.com/artifact/org.springframework/spring-jdbc --> <dependency><groupId>org.springframework</groupId><artifactId>spring-jdbc</artifactId><version>5.1.1.RELEASE</version> </dependency>
2、创建bean类
在这里，bean类包含对应于数据库中存在的字段的变量(以及setter和getter方法)。
Emp.java
示例
package com.nhooo.beans; public class Emp {
private int id;
private String name;
private float salary; public int getId() { return id;
}
public void setId(int id) { this.id = id;
}
public String getName() { return name;
}
public void setName(String name) { this.name = name;
}
public float getSalary() { return salary;
}
public void setSalary(float salary) { this.salary = salary;
} }
3、创建控制器类
在控制器类中， @PathVariable 批注将方法参数与临时URL绑定在一起。例如:
示例
@RequestMapping(value="/viewemp/{pageid}")
在此处，{}括号包含临时值。
EmpController.java
示例
package com.nhooo.controllers;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import com.nhooo.beans.Emp;
import com.nhooo.dao.EmpDao;
@Controller
public class EmpController { @Autowired EmpDao dao; @RequestMapping(value="/viewemp/{pageid}") public String edit(@PathVariable int pageid,Model m){ int total=5; if(pageid==1){} else{ pageid=(pageid-1)*total+1; } System.out.println(pageid);List<Emp> list=dao.getEmployeesByPage(pageid,total); m.addAttribute("msg", list);return "viewemp"; }
}
4、创建DAO类
让我们创建一个DAO类以访问数据库中所需的数据。
EmpDao.java
示例
package com.nhooo.dao; import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.List;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowMapper;
import com.nhooo.beans.Emp; public class EmpDao {
JdbcTemplate template; public void setTemplate(JdbcTemplate template) { this.template = template;
} public List<Emp> getEmployeesByPage(int pageid,int total){ String sql="select * from emp limit "+(pageid-1)+","+total; return template.query(sql,new RowMapper<Emp>(){ public Emp mapRow(ResultSet rs, int row) throws SQLException { Emp e=new Emp(); e.setId(rs.getInt(1)); e.setName(rs.getString(2)); e.setSalary(rs.getfloat(3)); return e; } });
}
}
5、在web.xml文件中提供控制器的条目
web.xml
示例
<?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"><display-name>SpringMVC</display-name><servlet> <servlet-name>spring</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>spring</servlet-name> <url-pattern>/</url-pattern> </servlet-mapping> </web-app>
6、在xml文件中定义Bean
spring-servlet.xml
示例
<?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/beanshttp://www.springframework.org/schema/beans/spring-beans.xsdhttp://www.springframework.org/schema/contexthttp://www.springframework.org/schema/context/spring-context.xsdhttp://www.springframework.org/schema/mvchttp://www.springframework.org/schema/mvc/spring-mvc.xsd"> <context:component-scan base-package="com.nhooo.controllers"></context:component-scan> <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="prefix" value="/WEB-INF/jsp/"></property> <property name="suffix" value=".jsp"></property> </bean> <bean id="ds" class="org.springframework.jdbc.datasource.DriverManagerDataSource"> <property name="driverClassName" value="com.mysql.jdbc.Driver"></property> <property name="url" value="jdbc:mysql://localhost:3306/test"></property> <property name="username" value=""></property> <property name="password" value=""></property> </bean> <bean id="jt" class="org.springframework.jdbc.core.JdbcTemplate"> <property name="dataSource" ref="ds"></property> </bean> <bean id="dao" class="com.nhooo.dao.EmpDao"> <property name="template" ref="jt"></property> </bean> </beans>
7、创建请求的页面
index.jsp
示例
<!DOCTYPE html> <html> <body> <a href="viewemp/1">View Employees</a> </body> </html>
8、创建视图组件
viewemp.jsp
示例
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!DOCTYPE html public "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<body>
<h1>Employees List</h1>
<table border="2" width="70%" cellpadding="2">
<tr><th>Id</th><th>Name</th><th>Salary</th></tr> <c:forEach var="emp" items="${msg}"> <tr> <td>${emp.id}</td> <td>${emp.name}</td> <td>${emp.salary}</td> </tr> </c:forEach> </table> <br/> <a href="/SpringMVCPaginationExample/viewemp/1">1</a> <a href="/SpringMVCPaginationExample/viewemp/2">2</a> <a href="/SpringMVCPaginationExample/viewemp/3">3</a>
</body>
</html>
输出:
