用myeclipse做一个增删改查的小程序

整个程序如下：用户登录--进入用户文章页面--可对文章进行增删改

数据库还是用SQL2005

create database Test use Test create table UserInfo
(
id int primary key identity(1,1), 
username varchar(20),
password varchar(20)
) create table Article
(
id int primary key identity(1,1), 
title varchar(50),
content varchar(100),
uid int FOREIGN KEY REFERENCES UserInfo(id)
) 
insert into UserInfo values('test','123')

package com.test.util; import java.sql.*;
public class DBcon {
private Connection con = null;
public DBcon()
{
try
{
Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
String url="jdbc:sqlserver://localhost:1433; DatabaseName=Test";
con= DriverManager.getConnection(url,"sa","123456"); 
System.out.println("数据库成功连接");
} catch (ClassNotFoundException e)
{
e.printStackTrace();
}catch (SQLException e) 
{
e.printStackTrace();
}
}

public Connection getCon() {
return con;
}

public void close() {
if (con != null) {
try {
con.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
} }

package com.test.entity; public class User {
private int id;
private String username;
private String password;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
}


Article.java

package com.test.entity; public class Article {
private int id;
private String title;
private String content;
private int uid;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public String getContent() {
return content;
}
public void setContent(String content) {
this.content = content;
}
public int getUid() {
return uid;
}
public void setUid(int uid) {
this.uid = uid;
} }

package com.test.service; import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List; import com.test.entity.Article;
import com.test.entity.User;
import com.test.util.DBcon;
public class TestService {
public User userLogin(String name,String password) {
User user = new User();
PreparedStatement ps = null;
ResultSet rs = null;
DBcon mycon = null;
String sql ="select * from UserInfo where username=?";
try{
mycon=new DBcon();
ps=mycon.getCon().prepareStatement(sql);
ps.setString(1, name);
rs=ps.executeQuery();
if(rs.next()) 
{
if(password.equals(rs.getString("password")))
{
//登录成功
user.setId(rs.getInt("id"));
user.setUsername(rs.getString("username"));
return user;
}else{
return null;
}
}else{
return null;
}
}catch (SQLException e) {
e.printStackTrace();
}finally {
try {
ps.close();
mycon.close();
} catch (SQLException e) {
e.printStackTrace();
} }
return user;
}

public List<Article> GetList(int userid) {
List<Article> list=new ArrayList<Article>();
PreparedStatement ps = null;
ResultSet rs = null;
DBcon mycon = null;
String sql ="select * from Article where uid=?";
try{
mycon=new DBcon();
ps=mycon.getCon().prepareStatement(sql);
ps.setInt(1, userid);
rs=ps.executeQuery();
while(rs.next()) 
{
Article article=new Article();
article.setId(rs.getInt("id"));
article.setTitle(rs.getString("title"));
article.setContent(rs.getString("content"));
article.setUid(rs.getInt("uid"));
list.add(article);
}
}catch (SQLException e) {
e.printStackTrace();
}finally {
try {
rs.close();
ps.close();
mycon.close();
} catch (SQLException e) {
e.printStackTrace();
} }
return list;


}

public boolean Add(Article article){
boolean flag = false;
PreparedStatement ps=null;
DBcon mycon=null;
String sql="insert into Article values(?,?,?)";
try{
mycon=new DBcon();
ps=mycon.getCon().prepareStatement(sql);
ps.setString(1, article.getTitle());
ps.setString(2, article.getContent());
ps.setInt(3, article.getUid());
int i=ps.executeUpdate();
if(i!=0){
flag=true;
}

}catch (SQLException e) {
e.printStackTrace();
}finally {
try {
ps.close();
mycon.close();
} catch (SQLException e) {
e.printStackTrace();
} }
return flag;

}
public Article GetArticle(int id)
{
Article article=null;
PreparedStatement ps=null;
DBcon mycon=null;
ResultSet rs=null;
String sql="select * from Article where id=?";
try{
mycon=new DBcon();
ps=mycon.getCon().prepareStatement(sql);
ps.setInt(1, id);
rs=ps.executeQuery();
if(rs.next())
{
article=new Article();
article.setId(rs.getInt("id"));
article.setTitle(rs.getString("title"));
article.setContent(rs.getString("content"));
article.setUid(rs.getInt("uid"));
}

}catch (SQLException e) {
e.printStackTrace();
}finally {
try {
ps.close();
mycon.close();
} catch (SQLException e) {
e.printStackTrace();
} }
return article;

}


public boolean Update(Article article){
boolean flag = false;
PreparedStatement ps=null;
DBcon mycon=null;
String sql="update Article set title=?,content=? where id=?";
try{
mycon=new DBcon();
ps=mycon.getCon().prepareStatement(sql);
ps.setString(1, article.getTitle());
ps.setString(2, article.getContent());
ps.setInt(3, article.getId());
int i=ps.executeUpdate();
if(i!=0){
flag=true;
}

}catch (SQLException e) {
e.printStackTrace();
}finally {
try {
ps.close();
mycon.close();
} catch (SQLException e) {
e.printStackTrace();
} }
return flag;
}

public boolean Delete(int id){
boolean flag = false;
PreparedStatement ps=null;
DBcon mycon=null;
String sql="delete from Article where id=?";
try{
mycon=new DBcon();
ps=mycon.getCon().prepareStatement(sql);
ps.setInt(1, id);
int i=ps.executeUpdate();
if(i!=0){
flag=true;
}

}catch (SQLException e) {
e.printStackTrace();
}finally {
try {
ps.close();
mycon.close();
} catch (SQLException e) {
e.printStackTrace();
} }
return flag;
}


}

package com.test.servlet;
import java.io.IOException;
import java.io.PrintWriter; import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse; import com.test.entity.Article;
import com.test.service.TestService; public class AddServlet extends HttpServlet { /**
* Constructor of the object.
*/
public AddServlet() {
super();
} /**
* Destruction of the servlet. <br>
*/
public void destroy() {
super.destroy(); // Just puts "destroy" string in log
// Put your code here
} /**
* The doGet method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to get.
* 
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException { request.setCharacterEncoding("GBK");
response.setCharacterEncoding("GBK");
response.setContentType("text/html");
PrintWriter out = response.getWriter();
int uid=0;
String title=request.getParameter("title");
String content=request.getParameter("content");
String s_id=request.getParameter("id");
if(s_id!=null)
uid=Integer.parseInt(s_id);

Article article=new Article();
article.setTitle(title);
article.setContent(content);
article.setUid(uid);

TestService ts=new TestService();
if(ts.Add(article))
out.print("<script>alert('添加成功');location.href='list?id="+uid+"'</script>");
else
out.print("<script>alert('添加失败');</script>");

} /**
* The doPost method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to post.
* 
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException { this.doGet(request, response);
} /**
* Initialization of the servlet. <br>
*
* @throws ServletException if an error occurs
*/
public void init() throws ServletException {
// Put your code here
} }

package com.test.servlet; import java.io.IOException;
import java.io.PrintWriter; import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse; import com.test.service.TestService; public class DeleteServlet extends HttpServlet { /**
* Constructor of the object.
*/
public DeleteServlet() {
super();
} /**
* Destruction of the servlet. <br>
*/
public void destroy() {
super.destroy(); // Just puts "destroy" string in log
// Put your code here
} /**
* The doGet method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to get.
* 
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException { int id=0,uid=0;
String s_id=request.getParameter("id");
String s_uid=request.getParameter("uid");
if(s_id!=null&&s_uid!=null){
id=Integer.parseInt(s_id);
uid=Integer.parseInt(s_uid);
}

TestService ts=new TestService();
if(ts.Delete(id))
response.sendRedirect("list?id="+uid);

} /**
* The doPost method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to post.
* 
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException { response.setContentType("text/html");
PrintWriter out = response.getWriter();
out
.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">");
out.println("<HTML>");
out.println(" <HEAD><TITLE>A Servlet</TITLE></HEAD>");
out.println(" <BODY>");
out.print(" This is ");
out.print(this.getClass());
out.println(", using the POST method");
out.println(" </BODY>");
out.println("</HTML>");
out.flush();
out.close();
} /**
* Initialization of the servlet. <br>
*
* @throws ServletException if an error occurs
*/
public void init() throws ServletException {
// Put your code here
} }

package com.test.servlet; import java.io.IOException;
import java.io.PrintWriter; import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse; import com.test.entity.Article;
import com.test.service.TestService; public class GetArticleServlet extends HttpServlet { /**
* Constructor of the object.
*/
public GetArticleServlet() {
super();
} /**
* Destruction of the servlet. <br>
*/
public void destroy() {
super.destroy(); // Just puts "destroy" string in log
// Put your code here
} /**
* The doGet method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to get.
* 
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException { this.doPost(request, response);
} /**
* The doPost method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to post.
* 
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException { int id=0;
String s_id=request.getParameter("id");
if(s_id!=null)
id=Integer.parseInt(s_id);

TestService ts=new TestService();
Article article=ts.GetArticle(id);
request.setAttribute("article", article);
// response.sendRedirect("update.jsp");
request.getRequestDispatcher("update.jsp").forward(request, response);

} /**
* Initialization of the servlet. <br>
*
* @throws ServletException if an error occurs
*/
public void init() throws ServletException {
// Put your code here
} }

package com.test.servlet; import java.io.IOException;
import java.io.PrintWriter;
import java.util.List; import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse; import com.test.entity.Article;
import com.test.service.TestService; public class ListServlet extends HttpServlet { /**
* Constructor of the object.
*/
public ListServlet() {
super();
} /**
* Destruction of the servlet. <br>
*/
public void destroy() {
super.destroy(); // Just puts "destroy" string in log
// Put your code here
} /**
* The doGet method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to get.
* 
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
int userid=0;
String id=request.getParameter("id");
if(id!=null)
userid=Integer.parseInt(id);
TestService ts=new TestService();
List<Article> list = ts.GetList(userid);
request.getSession().setAttribute("list", list);
response.sendRedirect("list.jsp");
} /**
* The doPost method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to post.
* 
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException { response.setContentType("text/html");
PrintWriter out = response.getWriter();
out
.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">");
out.println("<HTML>");
out.println(" <HEAD><TITLE>A Servlet</TITLE></HEAD>");
out.println(" <BODY>");
out.print(" This is ");
out.print(this.getClass());
out.println(", using the POST method");
out.println(" </BODY>");
out.println("</HTML>");
out.flush();
out.close();
} /**
* Initialization of the servlet. <br>
*
* @throws ServletException if an error occurs
*/
public void init() throws ServletException {
// Put your code here
} }

package com.test.servlet; import java.io.IOException;
import java.io.PrintWriter; import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse; import com.test.entity.User;
import com.test.service.TestService; public class LoginServlet extends HttpServlet { /**
* Constructor of the object.
*/
public LoginServlet() {
super();
} /**
* Destruction of the servlet. <br>
*/
public void destroy() {
super.destroy(); // Just puts "destroy" string in log
// Put your code here
} /**
* The doGet method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to get.
* 
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException { request.setCharacterEncoding("GBK");
response.setCharacterEncoding("GBK");
response.setContentType("text/html");
PrintWriter out = response.getWriter();
TestService ts=new TestService();
String username=request.getParameter("username");
String password=request.getParameter("password");
User user=ts.userLogin(username, password);
if(user==null)
out.print("<script>alert('登录失败');location.href='login.jsp'</script>");
else{
request.getSession().setAttribute("user", user);
out.print("<script>alert('登录成功');location.href='list?id="+user.getId()+"'</script>");
}


} /**
* The doPost method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to post.
* 
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException { this.doGet(request, response);
} /**
* Initialization of the servlet. <br>
*
* @throws ServletException if an error occurs
*/
public void init() throws ServletException {
// Put your code here
} }

package com.test.servlet; import java.io.IOException;
import java.io.PrintWriter; import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse; import com.test.entity.Article;
import com.test.service.TestService; public class UpdateServlet extends HttpServlet { /**
* Constructor of the object.
*/
public UpdateServlet() {
super();
} /**
* Destruction of the servlet. <br>
*/
public void destroy() {
super.destroy(); // Just puts "destroy" string in log
// Put your code here
} /**
* The doGet method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to get.
* 
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException { request.setCharacterEncoding("GBK");
response.setCharacterEncoding("GBK");
response.setContentType("text/html");
PrintWriter out = response.getWriter();
int id=0;
String title=request.getParameter("title");
String content=request.getParameter("content");
String s_id=request.getParameter("id");
if(s_id!=null)
id=Integer.parseInt(s_id);
TestService ts=new TestService();
Article article=ts.GetArticle(id);
article.setTitle(title);
article.setContent(content);
if(ts.Update(article))
out.print("<script>alert('修改成功');location.href='list?id="+article.getUid()+"'</script>");




} /**
* The doPost method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to post.
* 
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException { this.doGet(request, response);
} /**
* Initialization of the servlet. <br>
*
* @throws ServletException if an error occurs
*/
public void init() throws ServletException {
// Put your code here
} }

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" 
xmlns="http://java.sun.com/xml/ns/javaee" 
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee 
http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
<servlet>
<description>This is the description of my J2EE component</description>
<display-name>This is the display name of my J2EE component</display-name>
<servlet-name>LoginServlet</servlet-name>
<servlet-class>com.test.servlet.LoginServlet</servlet-class>
</servlet>
<servlet>
<description>This is the description of my J2EE component</description>
<display-name>This is the display name of my J2EE component</display-name>
<servlet-name>ListServlet</servlet-name>
<servlet-class>com.test.servlet.ListServlet</servlet-class>
</servlet>
<servlet>
<description>This is the description of my J2EE component</description>
<display-name>This is the display name of my J2EE component</display-name>
<servlet-name>AddServlet</servlet-name>
<servlet-class>com.test.servlet.AddServlet</servlet-class>
</servlet>
<servlet>
<description>This is the description of my J2EE component</description>
<display-name>This is the display name of my J2EE component</display-name>
<servlet-name>GetArticleServlet</servlet-name>
<servlet-class>com.test.servlet.GetArticleServlet</servlet-class>
</servlet>
<servlet>
<description>This is the description of my J2EE component</description>
<display-name>This is the display name of my J2EE component</display-name>
<servlet-name>UpdateServlet</servlet-name>
<servlet-class>com.test.servlet.UpdateServlet</servlet-class>
</servlet>
<servlet>
<description>This is the description of my J2EE component</description>
<display-name>This is the display name of my J2EE component</display-name>
<servlet-name>DeleteServlet</servlet-name>
<servlet-class>com.test.servlet.DeleteServlet</servlet-class>
</servlet> 
<servlet-mapping>
<servlet-name>LoginServlet</servlet-name>
<url-pattern>/login</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>ListServlet</servlet-name>
<url-pattern>/list</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>AddServlet</servlet-name>
<url-pattern>/add</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>GetArticleServlet</servlet-name>
<url-pattern>/get</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>UpdateServlet</servlet-name>
<url-pattern>/update</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>DeleteServlet</servlet-name>
<url-pattern>/delete</url-pattern>
</servlet-mapping>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
</web-app>