jsp+servlet+jdbc增删改查功能实现（一）
环境：
Eclipse Neon.3 Release (4.6.3),
Tomcat 8.5
Jdk1.8
数据库:MySQL
效果图如下
一、创建数据库t_user然后创建student表
create table student(
id INT NOT NULL AUTO_INCREMENT,
name VARCHAR(50) NOT NULL,
age INT(40) NOT NULL,
gender VARCHAR(30) NOT NULL,
major VARCHAR(50) NOT NULL,
PRIMARY KEY ( id )
);
二、创建WEB项目配置好tomcat和jdk后，添加mysql驱动包 mysql-connector-java-5.1.30-bin.jar
三、创建bean包和dbservlet包如下图，bean下创建Page类和StudentInfo类，dbservlet下创建AllServlet类
三、各页面代码：
1.Page页面
package bean;
public class Page {
private int totalPage;
private int currentPage;
private int totalRecord;
private int currentRecord;
private int pageSize=8;
//获得和设置当前页
public int getCurrentPage(){
return currentPage;
}
public void setCurrentPage(int currentRecord,int pageSize){
if(currentRecord%pageSize==0){
currentPage=currentRecord/pageSize;
}
else{
currentPage=currentRecord/pageSize+1;
}
}
//获得和设置当前记录
public int getCurrentRecord(){
return currentRecord;
}
public void setCurrentRecord(int currentRecord){
this.currentRecord=currentRecord;
}
//获得和设置每页记录数量
public int getPageSize(){
return pageSize;
}
public void setPageSize(int pageSize){
this.pageSize=pageSize;
}
//获得和设置总页数
public int getTotalPage(){
return totalPage;
}
public void setTotalPage(int totalRecord,int pageSize){
if(totalRecord%pageSize==0){
totalPage=totalRecord/pageSize;
}
else{
totalPage=totalRecord/pageSize+1;
}
}
//获得和设置总记录
public int getTotalRecord(){
return totalRecord;
}
public void setTotalRecord(int totalRecord){
this.totalRecord=totalRecord;
}
}
2.StudentInfo.java代码
package bean;
public class StudentInfo {
private int id; //学号
private String name; //姓名
private int age; //年龄
private String gender; //性别
private String major; //专业
public StudentInfo(){
}
public StudentInfo(int id,String name,int age,String gender,String major){
this.id=id;
this.name=name;
this.age=age;
this.gender=gender;
this.major=major;
}
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 int getAge(){
return age;
}
public void setAge(int age){
this.age=age;
}
public String getGender(){
return gender;
}
public void setGender(String gender){
this.gender=gender;
}
public String getMajor(){
return major;
}
public void setMajor(String major){
this.major=major;
}
}
3.AllServlet代码
package dbservlet;
import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.List;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import bean.Page;
import bean.StudentInfo;
public class AllServlet extends HttpServlet {
/**
*
*/
private static final long serialVersionUID = 1L;
//doPost方法
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
request.setCharacterEncoding("UTF-8");
response.setCharacterEncoding("UTF-8");
String methodName=request.getParameter("methodName");
int method=Integer.parseInt(methodName);
try {
switch(method)
{
case 0:
insert(request,response);
case 1:
difpage(request,response);
break;
case 2:
delete(request,response);
break;
case 3:
update(request,response);
break;
case 4:
update1(request,response);
break;
case 5:
dispatch(request,response);
break;
}
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
//doGet方法
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doPost(request,response);
}
//数据库连接方法
public Connection connect() throws ClassNotFoundException, SQLException{
Connection conn=null;
Class.forName("com.mysql.jdbc.Driver");
String url = "jdbc:mysql://localhost:3306/t_user?"
+ "user=root&password=19900908&useUnicode=true&characterEncoding=UTF8";
conn=DriverManager.getConnection(url);
return conn;
}
//关闭数据库资源
public void close(Statement stat,Connection conn) throws SQLException{
if(stat!=null){
stat.close();
}
if(conn!=null){
conn.close();
}
}
//插入方法
public void insert(HttpServletRequest request, HttpServletResponse response) throws ClassNotFoundException, SQLException{
Connection conn=null;
Statement stat=null;
String id=request.getParameter("id");
String name=request.getParameter("name");
String age=request.getParameter("age");
String gender=request.getParameter("gender");
String major=request.getParameter("major");
conn=connect();
stat=conn.createStatement();
stat.execute("insert into student(id,name,age,gender,major) values("+id+",'"+name+"',"+age+",'"+gender+"','"+major+"')");
close(stat,conn);
}
//查询方法
public ArrayList select(String id,String name) throws ClassNotFoundException, SQLException{
Connection conn=null;
Statement stat=null;
ResultSet rs=null;
conn=connect();
stat=conn.createStatement();
ArrayList result=new ArrayList();
if(id==""&&name==""){
rs=stat.executeQuery("select * from student");
}
if(id!=""&&name==""){
rs=stat.executeQuery("select * from student where id="+id+"");
}
if(id==""&&name!=""){
rs=stat.executeQuery("select * from student where name='"+name+"'");
}
if(id!=""&&name!=""){
rs=stat.executeQuery("select * from student where id="+id+" and name='"+name+"'");
}
while(rs.next())
{
StudentInfo st=new StudentInfo();
st.setId(rs.getInt("id"));
st.setName(rs.getString("name"));
st.setAge(rs.getInt("age"));
st.setGender(rs.getString("gender"));
st.setMajor(rs.getString("major"));
result.add(st);
}
if(rs!=null){
rs.close();
}
close(stat,conn);
return result;
}
//条件查询跳转
public void dispatch(HttpServletRequest request, HttpServletResponse response) throws ClassNotFoundException, SQLException, ServletException, IOException{
String id5=request.getParameter("id");
String name5=request.getParameter("name");
if(select(id5,name5).isEmpty()){
request.getRequestDispatcher("selectnothing.jsp").forward(request, response);
}
else{
request.setAttribute("result", select(id5,name5));
request.getRequestDispatcher("idnameselect.jsp").forward(request, response);
}
}
//设置分页相关参数方法
public Page setpage(HttpServletRequest request, HttpServletResponse response) throws ClassNotFoundException, SQLException{
String crd=request.getParameter("currentRecord");
//String id=request.getParameter("id");
// String name=request.getParameter("name");
ArrayList result=select("","");
Page pager=new Page();
pager.setTotalRecord(result.size());
pager.setTotalPage(result.size(),pager.getPageSize());
if(crd!=null)
{
int currentRecord=Integer.parseInt(crd);
pager.setCurrentRecord(currentRecord);
pager.setCurrentPage(currentRecord,pager.getPageSize());
}
return pager;
}
//获得分页显示的子集
public void difpage(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException, ClassNotFoundException, SQLException{
// String id=request.getParameter("id");
// String name=request.getParameter("name");
ArrayList result=select("","");
Page pager=new Page();
pager=setpage(request,response);
List subResult=null;
int currentRecord=pager.getCurrentRecord();
if(currentRecord==0){
if(pager.getTotalRecord()<8){
subResult=(List) result.subList(0,pager.getTotalRecord());
}
else{
subResult=(List) result.subList(0,pager.getPageSize());
}
}
else if(pager.getCurrentRecord()+pager.getPageSize()) result.subList(pager.getCurrentRecord(),pager.getCurrentRecord()+pager.getPageSize());
}
else
{
subResult=(List) result.subList(pager.getCurrentRecord(),result.size());
}
request.setAttribute("pager", pager);
request.setAttribute("subResult", subResult);
request.getRequestDispatcher("layout.jsp").forward(request, response);
}
//信息删除方法
public void delete(HttpServletRequest request, HttpServletResponse response) throws ClassNotFoundException, SQLException, ServletException, IOException{
Connection conn=null;
Statement stat=null;
conn=connect();
stat=conn.createStatement();
String id2=request.getParameter("id");
stat.execute("delete from student where id="+id2+"");
request.getRequestDispatcher("delete.jsp").forward(request, response);
}
//信息修改方法
public void update1(HttpServletRequest request, HttpServletResponse response) throws ClassNotFoundException, SQLException, ServletException, IOException{
String id4=request.getParameter("id");
request.setAttribute("result", select(id4,""));
request.getRequestDispatcher("update1.jsp").forward(request, response);
}
public void update(HttpServletRequest request, HttpServletResponse response) throws ClassNotFoundException, SQLException, ServletException, IOException{
Connection conn=null;
Statement stat=null;
String id3=request.getParameter("id");
String name3=request.getParameter("name");
String age3=request.getParameter("age");
String gender3=request.getParameter("gender");
String major3=request.getParameter("major");
conn=connect();
stat=conn.createStatement();
stat.execute("update student set id="+id3+",name='"+name3+"',age="+age3+",gender='"+gender3+"',major='"+major3+"' where id="+id3+"");
request.setAttribute("result", select(id3,""));
request.getRequestDispatcher("update.jsp").forward(request, response);
}
}
四、jsp页面见下一篇