ArrayList list = new ArrayList(); 你这个list 是类一级的
你的每次调用如果都使用这个,然后add 进去,那么每次都会往里面加数据了!public void setList(
list = new ArrayList(); // 每次拿数据前,需要把以前的数据清除掉。 好像 list.removeAll() 更好一些。
你的每次调用如果都使用这个,然后add 进去,那么每次都会往里面加数据了!public void setList(
list = new ArrayList(); // 每次拿数据前,需要把以前的数据清除掉。 好像 list.removeAll() 更好一些。
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Admin.javaimport java.sql.*;
public class Admin {
public String id;
public String name;
public String password;
public String sex;
public String tel;
public Admin()
{
}
public String getId()
{
return id;
}
public String getName()
{
return name;
}
public String getPassword()
{
return password;
}
public String getSex()
{
return sex;
}
public String getTel()
{
return tel;
}
public void setId(String id)
{
this.id=id;
}
public void setName(String name)
{
this.name=name;
}
public void setPassword(String pwd)
{
this.password=pwd;
} public void setSex(String sex)
{
this.sex=sex;
}
public void setTel(String tel)
{
this.tel=tel;
}
/*public ResultSet getAdmin(){
String sql="select * from admin ";
DBConnect db= new DBConnect();
ResultSet rs = db.executeQuery(sql);
return rs;
}*/
ArrayList list = new ArrayList();
public final static int PAGE_SIZE = 20;
public void setList(String sql,int pageNum) {
list.clear();
DBConnect db= new DBConnect();
ResultSet rs = db.executeQuery(sql);
try {
int i = 0;
while(rs.next()) {
i++;
if((i > PAGE_SIZE * (pageNum - 1)) && (i <= PAGE_SIZE * pageNum)) {
id=rs.getString("id");
name=rs.getString("name");
password=rs.getString("password");
tel=rs.getString("tel");
sex=rs.getString("sex");
Admin admin=new Admin();
admin.setId(id);
admin.setName(name);
admin.setPassword(password);
admin.setSex(sex);
admin.setTel(tel);
admin.addAdmin();
list.add(admin);
}
}
rs.close();
}
catch(Exception e) {
e.printStackTrace();
}
finally {
db.CloseDataBase();
}
}
public ArrayList getList() {
return this.list;
}
public int getPageCount() throws Exception {
DBConnect db= new DBConnect();
ResultSet rs = db.executeQuery("select count(*) from admin");
int count = 0;
while(rs.next()) {
count = rs.getInt(1);
}
db.CloseDataBase();
int pageCount = 0;
pageCount = (count % PAGE_SIZE == 0)?(count/PAGE_SIZE):(count/PAGE_SIZE + 1);
return pageCount;
}
public Admin getAdmin(String sql) {
DBConnect db= new DBConnect();
ResultSet rs = db.executeQuery(sql);
Admin admin =null;
try {
while(rs.next()) {
id=rs.getString("id");
name=rs.getString("name");
password=rs.getString("password");
tel=rs.getString("tel");
sex=rs.getString("sex");
admin=new Admin();
admin.setId(id);
admin.setName(name);
admin.setPassword(password);
admin.setSex(sex);
admin.setTel(tel);
admin.addAdmin();
}
rs.close();
}
catch(Exception e) {
e.printStackTrace();
}
finally {
db.CloseDataBase();
}
return admin;
}
public void updateAdmin(){
String sql="update admin "
+ " set name='"+name+"',sex='"+sex+"',tel='"+tel+"' "
+" where id='"+id+"' ";
DBConnect db= new DBConnect();
db.executeInsert(sql);
}
public void deleteAdmin(){
String sql="delete from admin where id ='"+id+"' ";
DBConnect db= new DBConnect();
db.executeDelete(sql);
}
public int deleteAdmin(String id){
int num=0;
String sql="delete from admin where id ='"+id+"' ";
DBConnect db= new DBConnect();
num=db.executeDelete(sql);
return num;
}
public void addAdmin() {
String sql="insert into admin(id,name,password,sex,tel) "
+"VALUES('"+id+"','"+name+"','"+password+"','"+sex+"','"+tel+"')";
DBConnect db= new DBConnect();
db.executeInsert(sql);
}
public boolean hasLogin(String id){ //检查该管理员是否已经注册
boolean f=true;
String sql="select id from admin where id ='"+id+"'";
DBConnect db =new DBConnect();
try{
ResultSet rs=db.executeQuery(sql);
if(rs.next()){ f=false;}
else{ f=true;}
}catch(Exception e){ e.getMessage();}
return f;
}
}
import java.sql.*;
import javax.servlet.*;
import javax.servlet.http.*;public class AdminControl extends HttpServlet{
public void doGet(HttpServletRequest req, HttpServletResponse res)
throws ServletException, IOException {
String id =req.getParameter("id");
int success = 0;
String action = req.getParameter("action");
Admin admin = null;
String message="";
if ("new".equalsIgnoreCase(action)) {
admin = doNew(req,res);
sendBean(req, res, admin, "/admin.jsp");
}
if ("update".equalsIgnoreCase(action)) {
try{
admin = doUpdate(req,res, id);
sendBean(req,res,admin,"/admin.jsp");
}
catch(SQLException e){}
}
if ("delete".equalsIgnoreCase(action)) {
try{
success = doDelete(id);
System.out.println("sssusss" + success);
}
catch(SQLException e){}
if (success != 1) {
doError(req, res, "AddAdmin: Delete unsuccessful. Rows affected: " + success);
} else {
res.sendRedirect("http://localhost:8080/ssglnit/admin.jsp");
}
}
}
public Admin doNew(HttpServletRequest req,HttpServletResponse res )
throws ServletException,IOException{
Admin admin= new Admin();
String id=req.getParameter("id");
String name=new String(req.getParameter("name").getBytes("ISO8859_1"));
String password= req.getParameter("password");
String sex =new String(req.getParameter("sex").getBytes("ISO8859_1"));
String tel=req.getParameter("tel");
if( hasLogin(req,res,id)){
admin.setId(id);
admin.setName(name);
admin.setPassword(password);
admin.setSex(sex);
admin.setTel(tel);
admin.addAdmin();
}
return admin;
} public Admin doUpdate(HttpServletRequest req,HttpServletResponse res , String id)
throws ServletException,IOException,SQLException {
Admin admin = new Admin();
String name=new String(req.getParameter("name").getBytes("ISO8859_1"));
String password= req.getParameter("password");
String sex =new String(req.getParameter("sex").getBytes("ISO8859_1"));
String tel=req.getParameter("tel");
admin.setId(id);
admin.setName(name);
admin.setPassword(password);
admin.setSex(sex);
admin.setTel(tel);
admin.updateAdmin();
return admin;
} public int doDelete(String id) throws SQLException {
int num=0;
Admin admin=new Admin();
num=admin.deleteAdmin(id);
System.out.println("成功" + id);
return num;
}
public void sendBean(HttpServletRequest req, HttpServletResponse res, Admin admin, String target)
throws ServletException, IOException {
req.setAttribute("admin", admin);
RequestDispatcher rd = getServletContext().getRequestDispatcher(target);
rd.forward(req, res);
}
public void doError(HttpServletRequest req, HttpServletResponse res, String str)
throws ServletException, IOException {
req.setAttribute("problem", str);
RequestDispatcher rd = getServletContext().getRequestDispatcher("/errorpage.jsp");
rd.forward(req, res);
}
public boolean hasLogin(HttpServletRequest req, HttpServletResponse res,String id)
throws ServletException, IOException{
boolean f=true;
String message="对不起,该房间已经被注册过了!";
Admin admin= new Admin();
f= admin.hasLogin(id);
if(f==false){
doError(req,res,message);
}
return f;
}
public void doPost(HttpServletRequest req, HttpServletResponse res)
throws ServletException, IOException { doGet(req, res); }
}