Jsp+servlet+javabean+dao------Students ' physique information management

1. Data class describing student information: Student

 Packageexam1; Public classStudent {Private intID; PrivateString name; PrivateString sex; Private intAge ; Private floatweight; Private floathight;  Public intgetId () {returnID; }     Public voidSetId (intID) { This. ID =ID; }     PublicString GetName () {returnname; }     Public voidsetName (String name) { This. Name =name; }     PublicString Getsex () {returnsex; }     Public voidsetsex (String sex) { This. Sex =sex; }     Public intGetage () {returnAge ; }     Public voidSetage (intAge ) {         This. Age =Age ; }     Public floatgetweight () {returnweight; }     Public voidSetweight (floatweight) {         This. Weight =weight; }     Public floatgethight () {returnhight; }     Public voidSethight (floathight) {         This. hight =hight; }    }

2. Database connection and shutdown tools: JavaBean

 Packageexam1;ImportJava.sql.*; Public classDbconnect {Private StaticString drivername= "Com.mysql.jdbc.Driver"; Private StaticString username= "Root"; Private StaticString userpwd= "123456"; Private StaticString dbname= "Student"; StaticConnection getdbconnection () {String url1= "jdbc:mysql://localhost:3306/" +DbName; String Url2= "? user=" +username+ "&password=" +userpwd; String Url3= "&useunicode=true&characterencoding=utf-8"; String URL=url1+url2+Url3; Try{class.forname (drivername); Connection Con=drivermanager.getconnection (URL); returncon; }Catch(Exception e) {e.printstacktrace (); }        return NULL; }     Public Static voidclosedb (Connection con,preparedstatement pstmt,resultset rs) {Try{            if(rs!=NULL) Rs.close (); if(pstmt!=NULL) Pstmt.close (); if(con!=NULL) Con.close (); }Catch(SQLException e) {e.printstacktrace (); }    }}

3. Implementing a combination of database access and business logic DAO

 Packageexam1;ImportJava.sql.*;Importjava.util.ArrayList;Importjava.util.List; Public  classStudentdaoImplementsIstudentdao {protected Static FinalString fields_insert= "Id,name,sex,age,weight,hight"; protected StaticString insert_sql= "INSERT into Stu_info (" +fields_insert+ ")" + "VALUES (?,?,?,?,?,?)"; protected StaticString select_sql= "Select" +fields_insert+ "from Stu_info where id=?"; protected StaticString update_sql= "UPDATE stu_info Set" + "id=?,name=?,sex=?,age=?,weight=?,hight=? where id=? "; protected StaticString delete_sql= "DELETE from Stu_info where id=?";  PublicStudent Create (Student stu)throwsexception{Connection con=NULL; PreparedStatement prestmt=NULL; ResultSet RS=NULL; Try{con=dbconnect.getdbconnection (); Prestmt=con.preparestatement (Insert_sql); Prestmt.setint (1, Stu.getid ()); Prestmt.setstring (2, Stu.getname ()); Prestmt.setstring (3, Stu.getsex ()); Prestmt.setint (4, Stu.getage ()); Prestmt.setfloat (5, Stu.getweight ()); Prestmt.setfloat (6, Stu.gethight ());         Prestmt.executeupdate (); }Catch(Exception e) {}finally{dbconnect.closedb (Con, prestmt, RS); }         returnStu; } @Override Public voidRemove (Student stu)throwsException {//TODO auto-generated Method Stub} @Override PublicStudent Find (Student stu)throwsException {Connection con=NULL; PreparedStatement prestmt=NULL; ResultSet RS=NULL; Student STU2=NULL; Try{con=dbconnect.getdbconnection (); Prestmt=con.preparestatement (Select_sql); Prestmt.setint (1, Stu.getid ()); RS=Prestmt.executequery (); if(Rs.next ()) {STU2=NewStudent (); Stu2.setid (Rs.getint (1)); Stu2.setname (Rs.getstring (2)); Stu2.setsex (Rs.getstring (3)); Stu2.setage (Rs.getint (4)); Stu2.setweight (Rs.getfloat (5)); Stu2.sethight (Rs.getfloat (6)); }        }Catch(Exception e) {}finally{dbconnect.closedb (Con, prestmt, RS); }        returnSTU2; } @Override PublicList<student> FindAll ()throwsException {Connection con=NULL; PreparedStatement prepstmt=NULL; ResultSet RS=NULL; List<Student> student=NewArraylist<student>(); Con=dbconnect.getdbconnection (); Prepstmt=con.preparestatement ("SELECT * from Stu_info");  while(Rs.next ()) {Student STU2=NewStudent (); Stu2.setid (Rs.getint (1)); Stu2.setname (Rs.getstring (2)); Stu2.setsex (Rs.getstring (3)); Stu2.setage (Rs.getint (4)); Stu2.setweight (Rs.getfloat (5)); Stu2.sethight (Rs.getfloat (6));                Student.add (STU2);            } dbconnect.closedb (Con, prepstmt, RS); returnstudent; } @Override Public voidUpdate (Student Stu)throwsException {Connection con=NULL; PreparedStatement prestmt=NULL; ResultSet RS=NULL; Try{con=dbconnect.getdbconnection (); Prestmt=con.preparestatement (Update_sql); Prestmt.setint (1, Stu.getid ()); Prestmt.setstring (2, Stu.getname ()); Prestmt.setstring (3, Stu.getsex ()); Prestmt.setint (4, Stu.getage ()); Prestmt.setfloat (5, Stu.getweight ()); Prestmt.setfloat (6, Stu.gethight ()); intRowcount=prestmt.executeupdate (); if(rowcount==0){                Throw NewException ("Update error:student Id:" +Stu.getid ()); }        }Catch(Exception e) {}finally{dbconnect.closedb (Con, prestmt, RS); }            }}

4. Interfaces to implement business logic processing

 Packageexam1;Importjava.util.List; Public InterfaceIstudentdao { Public AbstractStudent Create (Student stu)throwsException;  Public Abstract voidRemove (Student stu)throwsException;  Public AbstractStudent Find (Student stu)throwsException;  Public AbstractList<student>findall ()throwsException;  Public Abstract voidUpdate (Student Stu)throwsException;}

Jsp+servlet+javabean+dao------Students ' physique information management