MVC实现增删改查的小例子(精)

MVC

作者：深蓝王子

SearchList.jsp

92期学员信息如下

String sql="select * from student order by id";

java.util.List list=sBean.getSearch(sql;

for(Iterator it=list.iterator(;it.hasNext(;{

//获得JavaBean的一个对象

jBean=(com.jq92.bean.JavaBeanit.next(;

}

Update.jsp

您要更新的数据如下：

查询

Insert.jsp

92期学院管理页面

查询

Error.jsp

对不起，您<%=request.getAttribute("error" %>失败

Servlet部分

Update.java

public void doPost(HttpServletRequest request, HttpServletResponse response throws ServletException, IOException {

//获得前台表单信息

String sid=request.getParameter("id";

int id=Integer.parseInt(sid;

String name=request.getParameter("name";

String password=request.getParameter("password";

String sex=request.getParameter("sex";

String Sage=request.getParameter("age";

int age=Integer.parseInt(Sage;

//封装到JavaBean对象中去

JavaBean jBean=new JavaBean(;

jBean.setId(id;

jBean.setName(name;

jBean.setPassword(password;

jBean.setSex(sex;

jBean.setAge(age;

String sql="update student set name=?,password=?,sex=?,age=? where id=?"; SqlBean sBean=new SqlBean(;

int count=sBean.getUpdate(sql, jBean;

String url="";

if(count>0{

url="SearchList.jsp";

}

else{

url="Error.jsp";

request.setAttribute("error", "更新";

}

request.getRequestDispatcher(url.forward(request, response;

}

SearchById.java

public void doPost(HttpServletRequest request, HttpServletResponse response throws ServletException, IOException {

//获得id

String sid=request.getParameter("id";

int id=Integer.parseInt(sid;

String sql="select * from student where id=?";

SqlBean sBean=new SqlBean(;

JavaBean jBean=sBean.getSearchById(sql, id;

//ID

request.setAttribute("id", jBean.getId(;

//姓名

request.setAttribute("name",jBean.getName(;

//密码

request.setAttribute("password", jBean.getPassword(;

//性别

String sex="";

String man="";

String woman="";

if(jBean.getSex(!=null{

sex=jBean.getSex(.trim(;

if(sex.equals("男"{

man="checked";

}

else{

woman="checked";

}

request.setAttribute("man",man;

request.setAttribute("woman",woman;

//年龄

request.setAttribute("age", jBean.getAge(;

//转发

request.getRequestDispatcher("Update.jsp".forward(request, response;

}

Insert.java

public void doPost(HttpServletRequest request, HttpServletResponse response throws ServletException, IOException {

//获取前台页面信息

String name=request.getParameter("name";

String password=request.getParameter("password";

String sex=request.getParameter("sex";

String Sage=request.getParameter("age";

int age=Integer.parseInt(Sage;

//封装到JavaBean对象中

com.jq92.bean.JavaBean jBean=new com.jq92.bean.JavaBean(; jBean.setName(name;

jBean.setPassword(password;

jBean.setSex(sex;

jBean.setAge(age;

//调用模型层

String sql="insert into student values(?,?,?,?";

SqlBean sBean=new SqlBean(;

int count=sBean.getInsert(sql, jBean;

String url="";

if(count>0{

url="SearchList.jsp";

}

else{

url="Error.jsp";

request.setAttribute("error","注册";

}

//转发

request.getRequestDispatcher(url.forward(request, response;

}

Delete.java

public void doPost(HttpServletRequest request, HttpServletResponse response throws ServletException, IOException {

//获得删除超链接传来的参数

String sId=request.getParameter("id";

int id=Integer.parseInt(sId;

//调用模型层删除方法

String sql="delete from student where id=?";

SqlBean sBean=new SqlBean(;

int count=sBean.getDelete(sql, id;

String url="";

if(count>0{

url="SearchList.jsp";

}

else{

url="Error.jsp";

request.setAttribute("error", "删除";

}

request.getRequestDispatcher(url.forward(request, response;

}

JavaBean.java

package com.jq92.bean;

public class JavaBean {

private int id;

private String name;

private String password;

private String sex;

private int age;

public int getAge( {

return age;

}

public void setAge(int age { this.age = age;

}

public int getId( {

return id;

}

public void setId(int id {

this.id = id;

}

public String getName( {

return name;

}

public void setName(String name { https://www.360docs.net/doc/b8415470.html, = name;

}

public String getPassword( { return password;

}

public void setPassword(String password { this.password = password;

}

public String getSex( {

return sex;

}

public void setSex(String sex {

this.sex = sex;

}

SqlBean.java

package com.jq92.bean;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.PreparedStatement; import java.sql.ResultSet;

import java.sql.SQLException;

import java.util.ArrayList;

import java.util.List;

public class SqlBean {

Connection con;

PreparedStatement pre;

ResultSet rs;

public SqlBean({

try {

Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver";

} catch (ClassNotFoundException e {

// TODO 自动生成 catch 块

e.printStackTrace(;

}

try {

con=DriverManager.getConnection("jdbc:microsoft:sqlserver://localhost:1433;Database Name=jq92Model2","sa","sa";

} catch (SQLException e {

// TODO 自动生成 catch 块

e.printStackTrace(;

}

public int getInsert(String sql,JavaBean jBean{

int count=0;

try {

pre=con.prepareStatement(sql;

pre.setString(1,jBean.getName(;

pre.setString(2,jBean.getPassword(;

pre.setString(3, jBean.getSex(;

pre.setInt(4, jBean.getAge(;

count=pre.executeUpdate(;

} catch (SQLException e {

// TODO 自动生成 catch 块

e.printStackTrace(;

}

finally{

try{

pre.close(;

con.close(;

}catch (SQLException e {

// TODO 自动生成 catch 块

e.printStackTrace(;

}

return count;

}

public int getDelete(String sql,int id{ int count=0;

try {

pre=con.prepareStatement(sql; pre.setInt(1, id;

count=pre.executeUpdate(;

} catch (SQLException e {

// TODO 自动生成 catch 块

e.printStackTrace(;

}

finally{

try{

pre.close(;

}catch (SQLException e {

// TODO 自动生成 catch 块

e.printStackTrace(;

}

return count;

}

public JavaBean getSearchById(String sql,int id{ JavaBean jBean=new JavaBean(;

try {

pre=con.prepareStatement(sql;

pre.setInt(1, id;

rs=pre.executeQuery(;

while(rs.next({

jBean.setId(rs.getInt("id";

jBean.setName(rs.getString("name";

jBean.setPassword(rs.getString("password"; jBean.setSex(rs.getString("sex";

jBean.setAge(rs.getInt("age";

}

} catch (SQLException e {

// TODO 自动生成 catch 块

e.printStackTrace(;

}

public int getUpdate(String sql,JavaBean jBean{ int count=0;

try {

pre=con.prepareStatement(sql;

pre.setString(1,jBean.getName(;

pre.setString(2, jBean.getPassword(;

pre.setString(3, jBean.getSex(;

pre.setInt(4, jBean.getAge(;

pre.setInt(5, jBean.getId(;

count=pre.executeUpdate(;

} catch (SQLException e {

// TODO 自动生成 catch 块

e.printStackTrace(;

}

finally{

try{

pre.close(;

con.close(;

}catch (SQLException e {

// TODO 自动生成 catch 块

e.printStackTrace(;

}

public List getSearch(String sql{

List list=new ArrayList(;

//获得prepareStatement对象

try {

pre=con.prepareStatement(sql;

rs=pre.executeQuery(;

while(rs.next({

JavaBean jBean=new JavaBean(;

jBean.setId(rs.getInt("id";

jBean.setName(rs.getString("name"; jBean.setPassword(rs.getString("password"; jBean.setSex(rs.getString("sex";

jBean.setAge(rs.getInt("age";

list.add(jBean;

}

} catch (SQLException e {

// TODO 自动生成 catch 块

e.printStackTrace(;

}

finally{

try{

pre.close(;

con.close(;

}catch (SQLException e {

// TODO 自动生成 catch 块

e.printStackTrace(;

}

return list;

}

Filter过滤器编码转换

package com.jq92.filter;

import java.io.IOException;

import javax.servlet.Filter;

import javax.servlet.FilterChain;

import javax.servlet.FilterConfig;

import javax.servlet.ServletException;

import javax.servlet.ServletRequest;

import javax.servlet.ServletResponse;

public class EncodingFilter implements Filter {

String encoding="";

public void destroy( {

// TODO 自动生成方法存根

}

public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain throws IOException, ServletException {

// TODO 自动生成方法存根

request.setCharacterEncoding(encoding;

chain.doFilter(request, response;

}

public void init(FilterConfig config throws ServletException { // TODO 自动生成方法存根

encoding=config.getInitParameter("encoding";

}

web.xml

xmlns="https://www.360docs.net/doc/b8415470.html,/xml/ns/j2ee"

xmlns:xsi="https://www.360docs.net/doc/b8415470.html,/2001/XMLSchema-instance" xsi:schemaLocation="https://www.360docs.net/doc/b8415470.html,/xml/ns/j2ee

https://www.360docs.net/doc/b8415470.html,/xml/ns/j2ee/web-app_2_4.xsd">

com.jq92.filter.EncodingFilter

encoding

utf-8

This is the description of my J2EE component

This is the display name of my J2EE component

Insert

com.jq92.servlet.Insert

This is the description of my J2EE component

This is the display name of my J2EE component

Delete

com.jq92.servlet.Delete

This is the description of my J2EE component This is the display name of my J2EE component SearchById

com.jq92.servlet.SearchById

This is the description of my J2EE component This is the display name of my J2EE component Update

com.jq92.servlet.Update

Insert

/Insert

Delete

/Delete

SearchById

/SearchById

Update

/Update