how to create dao for create,read,update and delete?
/*
*ConnectionManager
*
*
*Version:1.0
*
*Date:25-Nov-2011
*
*/
package com.student.dao;
import java.sql.*;
import org.apache.log4j.Logger;
import org.apache.log4j.PropertyConfigurator;
public class ConnectionManager {
static Connection con;
static String url;
static final Logger logger = Logger.getLogger(ConnectionManager.class);
public static Connection getConnection() {
PropertyConfigurator.configure("log4j.properties");
try {
String url = "jdbc:oracle:thin:@172.24.137.30:1521:ora10g";
// assuming "DataSource" is your DataSource name
Class.forName("oracle.jdbc.OracleDriver");
try {
con = DriverManager.getConnection(url, "e533121", "project1");
// assuming your SQL Server's username is "username"
// and password is "password"
}
catch (SQLException ex) {
ex.printStackTrace();
}
}
catch (ClassNotFoundException e) {// "logger" prints in to a file;
// Normally used to trace the
// process
logger.error(e);
}
return con;
}
}
createid:
/*
*CollegeRegistrationDao
*
*
*Version:1.0
*
*Date:31-Nov-2011
*
*/
package com.student.dao;
import java.sql.*;
import com.student.beans.*;
import org.apache.log4j.Logger;
import org.apache.log4j.PropertyConfigurator;
public class CreateIdDAO {
static Connection currentCon = null;
static ResultSet rs = null;
static PreparedStatement pstmt = null;
static ResultSet rs1 = null;
static PreparedStatement pstmt1 = null;
static final Logger logger = Logger.getLogger(CreateIdDAO.class);
public static StudentBean register(StudentBean bean) {
/**
* method to search student
*
* @533026,533121
*
*/
// preparing some objects for connection
Statement stmt = null;
PropertyConfigurator.configure("log4j.properties");
try {
// connect to DataBase
// connect to DataBase
currentCon = ConnectionManager.getConnection();
stmt = currentCon.createStatement();
String getMax = "select Max(std_id) from studentids";
rs1 = stmt.executeQuery(getMax);
rs1.next();
int maxId = rs1.getInt(1);
System.out.println(maxId);
int nextId = maxId + 1;
String stdId = "S" + Integer.toString(nextId);
String query1 = "insert into studentids values(?)";
pstmt1 = currentCon.prepareStatement(query1);
pstmt1.setInt(1, nextId);
pstmt1.executeUpdate();
bean.setStudentId(stdId);
} catch (Exception ex) {// "logger" prints in to a file; Normally used
// to trace the process
logger.error("Registration failed: An Exception has occurred! "
+ ex);
}
// exception handling
finally {
if (rs != null) {
try {
rs.close();
} catch (Exception e) {
}
rs = null;
}
if (stmt != null) {
try {
stmt.close();
} catch (Exception e) {
}
stmt = null;
}
if (currentCon != null) {
try {
currentCon.close();
} catch (Exception e) {
}
currentCon = null;
}
}
return bean;
}
}
registration:
try {
// connect to DataBase
// connect to DataBase
currentCon = ConnectionManager.getConnection();
String stdId=bean.getStudentId();
System.out.println(stdId);
// query for inserting into the table
String query = "insert into newstudent(std_id,std_name,maths,social,hindi,science,english) values(?,?,?,?,?,?,?)";
pstmt = currentCon.prepareStatement(query);
// inserting values
pstmt.setString(1,stdId);
pstmt.setString(2,bean.getStudentName());
pstmt.setInt(3, bean.getMaths());
pstmt.setInt(4, bean.getSocial());
pstmt.setInt(5, bean.getHindi());
pstmt.setInt(6, bean.getScience());
pstmt.setInt(7, bean.getEnglish());
pstmt.executeUpdate();
bean.setValid(true);
}
delete: try {
String std = bean.getStudentId();
PropertyConfigurator.configure("log4j.properties");
String searchQuery = "delete from newstudent where std_id='"+ std + "'";
bean.setValid(true);
// // "logger" prints in to a file; Normally used to trace the process
logger.info("Your employee id is " + std);
logger.info("Query: " + searchQuery);
}
catch (Exception ex) {
logger.error("Log In failed: An Exception has occurred! " + ex);
}
search:
Statement stmt = null;
String username = bean.getStudentId();
String searchQuery = "select * from newstudent where std_id ='"
+ username + "' ";
// "logger" prints in to a file; Normally used to trace the process
logger.info("Student ID is " + username);
logger.info("Query: " + searchQuery);
try {
// connect to DB
currentCon = ConnectionManager.getConnection();
stmt = currentCon.createStatement();
rs = stmt.executeQuery(searchQuery);
boolean more = rs.next();
// if user does not exist set the isValid variable to false
if (!more) {
logger
.warn("Sorry, you are not a registered user! Please sign up first");
bean.setValid(false);
}
// if user exists set the isValid variable to true
else if (more) {
String studentId = rs.getString("std_id");
String studentName = rs.getString("std_NAME");
int maths = rs.getInt("maths");
int social = rs.getInt("social");
int hindi = rs.getInt("hindi");
int science = rs.getInt("science");
int english = rs.getInt("english");
bean.setStudentId(studentId);
bean.setStudentName(studentName);
bean.setMaths(maths);
bean.setSocial(social);
bean.setHindi(hindi);
bean.setScience(science);
bean.setEnglish(english);
bean.setValid(true);
int total=maths+social+hindi+science+english;
if(total>=450){
bean.setGrade("A+");
}
if(total>=400 && total<=449){
bean.setGrade("A");
}
if(total>=350 && total<=399){
bean.setGrade("B");
}
if(total>=300 && total<=349){
bean.setGrade("C");
}
if(total>=250 && total<=299){
bean.setGrade("D");
}
if(total>=200 && total<=249){
bean.setGrade("E");
}
if(total<200){
bean.setGrade("Fail");
}
}
}
profile and update:
Statement stmt = null;
String username = bean.getStudentId();
// query to select row from College using College_Id
String searchQuery = "select * from newstudent where std_Id='"
+ username + "' ";
// "logger" prints in to a file; Normally used to trace the process
logger.info("Your user name is " + username);
logger.info("Query: " + searchQuery);
try {
// connect to DataBase
currentCon = ConnectionManager.getConnection();
stmt = currentCon.createStatement();
rs = stmt.executeQuery(searchQuery);
boolean more = rs.next();
// check for rows
if (more) {
String studentId = rs.getString("std_id");
String studentName = rs.getString("std_NAME");
int maths = rs.getInt("maths");
int social = rs.getInt("social");
int hindi = rs.getInt("hindi");
int science = rs.getInt("science");
int english = rs.getInt("english");
bean.setStudentId(studentId);
bean.setStudentName(studentName);
bean.setMaths(maths);
bean.setSocial(social);
bean.setHindi(hindi);
bean.setScience(science);
bean.setEnglish(english);
bean.setValid(true);
} else {
bean.setValid(false);
}
}
catch (Exception ex) {
logger.error("Log In failed: An Exception has occurred! " + ex);
}
public static StudentBean register(StudentBean bean) {
Statement stmt = null;
/**
* method to search student
*
* @533026
*
*/
// preparing some objects for connection
/*
* String sName = bean.getStudentName(); String searchQuery =
* "select * from Student where Student_Name='" + sName + "' "; //
* "System.out.println" prints in the console; Normally used to trace
* the process System.out.println("Your user name is " + sName);
* System.out.println("Query: "+searchQuery);
*/
PropertyConfigurator.configure("log4j.properties");
try {
// connect to DataBase
currentCon = ConnectionManager.getConnection();
// if user does not exist set the isValid variable to false
// query for inserting into the table
String sid = bean.getStudentId();
String sn = bean.getStudentName();
int ma = bean.getMaths();
int sc = bean.getSocial();
int hi = bean.getHindi();
int si = bean.getScience();
int eng = bean.getEnglish();
String query = "update newstudent set std_name='" + sn + "',maths=" + ma + ",social="
+ sc + ",hindi=" + hi + ",science=" + si + ",english=" + eng + " where std_id='" + sid + "'";
// "logger" prints in to a file; Normally used to trace the process
logger.info(query);
pstmt = currentCon.prepareStatement(query);
pstmt.executeUpdate();
} catch (Exception ex) {
logger.error("Log In failed: An Exception has occurred! " + ex);
}
/*
*ConnectionManager
*
*
*Version:1.0
*
*Date:25-Nov-2011
*
*/
package com.student.dao;
import java.sql.*;
import org.apache.log4j.Logger;
import org.apache.log4j.PropertyConfigurator;
public class ConnectionManager {
static Connection con;
static String url;
static final Logger logger = Logger.getLogger(ConnectionManager.class);
public static Connection getConnection() {
PropertyConfigurator.configure("log4j.properties");
try {
String url = "jdbc:oracle:thin:@172.24.137.30:1521:ora10g";
// assuming "DataSource" is your DataSource name
Class.forName("oracle.jdbc.OracleDriver");
try {
con = DriverManager.getConnection(url, "e533121", "project1");
// assuming your SQL Server's username is "username"
// and password is "password"
}
catch (SQLException ex) {
ex.printStackTrace();
}
}
catch (ClassNotFoundException e) {// "logger" prints in to a file;
// Normally used to trace the
// process
logger.error(e);
}
return con;
}
}
createid:
/*
*CollegeRegistrationDao
*
*
*Version:1.0
*
*Date:31-Nov-2011
*
*/
package com.student.dao;
import java.sql.*;
import com.student.beans.*;
import org.apache.log4j.Logger;
import org.apache.log4j.PropertyConfigurator;
public class CreateIdDAO {
static Connection currentCon = null;
static ResultSet rs = null;
static PreparedStatement pstmt = null;
static ResultSet rs1 = null;
static PreparedStatement pstmt1 = null;
static final Logger logger = Logger.getLogger(CreateIdDAO.class);
public static StudentBean register(StudentBean bean) {
/**
* method to search student
*
* @533026,533121
*
*/
// preparing some objects for connection
Statement stmt = null;
PropertyConfigurator.configure("log4j.properties");
try {
// connect to DataBase
// connect to DataBase
currentCon = ConnectionManager.getConnection();
stmt = currentCon.createStatement();
String getMax = "select Max(std_id) from studentids";
rs1 = stmt.executeQuery(getMax);
rs1.next();
int maxId = rs1.getInt(1);
System.out.println(maxId);
int nextId = maxId + 1;
String stdId = "S" + Integer.toString(nextId);
String query1 = "insert into studentids values(?)";
pstmt1 = currentCon.prepareStatement(query1);
pstmt1.setInt(1, nextId);
pstmt1.executeUpdate();
bean.setStudentId(stdId);
} catch (Exception ex) {// "logger" prints in to a file; Normally used
// to trace the process
logger.error("Registration failed: An Exception has occurred! "
+ ex);
}
// exception handling
finally {
if (rs != null) {
try {
rs.close();
} catch (Exception e) {
}
rs = null;
}
if (stmt != null) {
try {
stmt.close();
} catch (Exception e) {
}
stmt = null;
}
if (currentCon != null) {
try {
currentCon.close();
} catch (Exception e) {
}
currentCon = null;
}
}
return bean;
}
}
registration:
try {
// connect to DataBase
// connect to DataBase
currentCon = ConnectionManager.getConnection();
String stdId=bean.getStudentId();
System.out.println(stdId);
// query for inserting into the table
String query = "insert into newstudent(std_id,std_name,maths,social,hindi,science,english) values(?,?,?,?,?,?,?)";
pstmt = currentCon.prepareStatement(query);
// inserting values
pstmt.setString(1,stdId);
pstmt.setString(2,bean.getStudentName());
pstmt.setInt(3, bean.getMaths());
pstmt.setInt(4, bean.getSocial());
pstmt.setInt(5, bean.getHindi());
pstmt.setInt(6, bean.getScience());
pstmt.setInt(7, bean.getEnglish());
pstmt.executeUpdate();
bean.setValid(true);
}
delete:
try
{
String std = bean.getStudentId();
PropertyConfigurator.configure("log4j.properties");
String searchQuery = "delete from newstudent where std_id='"+ std + "'";
bean.setValid(true);
// // "logger" prints in to a file; Normally used to trace the process
logger.info("Your employee id is " + std);
logger.info("Query: " + searchQuery);
}
catch (Exception ex) {
logger.error("Log In failed: An Exception has occurred! " + ex);
}
search:
Statement stmt = null;
String username = bean.getStudentId();
String searchQuery = "select * from newstudent where std_id ='"
+ username + "' ";
// "logger" prints in to a file; Normally used to trace the process
logger.info("Student ID is " + username);
logger.info("Query: " + searchQuery);
try {
// connect to DB
currentCon = ConnectionManager.getConnection();
stmt = currentCon.createStatement();
rs = stmt.executeQuery(searchQuery);
boolean more = rs.next();
// if user does not exist set the isValid variable to false
if (!more) {
logger
.warn("Sorry, you are not a registered user! Please sign up first");
bean.setValid(false);
}
// if user exists set the isValid variable to true
else if (more) {
String studentId = rs.getString("std_id");
String studentName = rs.getString("std_NAME");
int maths = rs.getInt("maths");
int social = rs.getInt("social");
int hindi = rs.getInt("hindi");
int science = rs.getInt("science");
int english = rs.getInt("english");
bean.setStudentId(studentId);
bean.setStudentName(studentName);
bean.setMaths(maths);
bean.setSocial(social);
bean.setHindi(hindi);
bean.setScience(science);
bean.setEnglish(english);
bean.setValid(true);
int total=maths+social+hindi+science+english;
if(total>=450){
bean.setGrade("A+");
}
if(total>=400 && total<=449){
bean.setGrade("A");
}
if(total>=350 && total<=399){
bean.setGrade("B");
}
if(total>=300 && total<=349){
bean.setGrade("C");
}
if(total>=250 && total<=299){
bean.setGrade("D");
}
if(total>=200 && total<=249){
bean.setGrade("E");
}
if(total<200){
bean.setGrade("Fail");
}
}
}
profile and update:
Statement stmt = null;
String username = bean.getStudentId();
// query to select row from College using College_Id
String searchQuery = "select * from newstudent where std_Id='"
+ username + "' ";
// "logger" prints in to a file; Normally used to trace the process
logger.info("Your user name is " + username);
logger.info("Query: " + searchQuery);
try {
// connect to DataBase
currentCon = ConnectionManager.getConnection();
stmt = currentCon.createStatement();
rs = stmt.executeQuery(searchQuery);
boolean more = rs.next();
// check for rows
if (more) {
String studentId = rs.getString("std_id");
String studentName = rs.getString("std_NAME");
int maths = rs.getInt("maths");
int social = rs.getInt("social");
int hindi = rs.getInt("hindi");
int science = rs.getInt("science");
int english = rs.getInt("english");
bean.setStudentId(studentId);
bean.setStudentName(studentName);
bean.setMaths(maths);
bean.setSocial(social);
bean.setHindi(hindi);
bean.setScience(science);
bean.setEnglish(english);
bean.setValid(true);
} else {
bean.setValid(false);
}
}
catch (Exception ex) {
logger.error("Log In failed: An Exception has occurred! " + ex);
}
public static StudentBean register(StudentBean bean) {
Statement stmt = null;
/**
* method to search student
*
* @533026
*
*/
// preparing some objects for connection
/*
* String sName = bean.getStudentName(); String searchQuery =
* "select * from Student where Student_Name='" + sName + "' "; //
* "System.out.println" prints in the console; Normally used to trace
* the process System.out.println("Your user name is " + sName);
* System.out.println("Query: "+searchQuery);
*/
PropertyConfigurator.configure("log4j.properties");
try {
// connect to DataBase
currentCon = ConnectionManager.getConnection();
// if user does not exist set the isValid variable to false
// query for inserting into the table
String sid = bean.getStudentId();
String sn = bean.getStudentName();
int ma = bean.getMaths();
int sc = bean.getSocial();
int hi = bean.getHindi();
int si = bean.getScience();
int eng = bean.getEnglish();
String query = "update newstudent set std_name='" + sn + "',maths=" + ma + ",social="
+ sc + ",hindi=" + hi + ",science=" + si + ",english=" + eng + " where std_id='" + sid + "'";
// "logger" prints in to a file; Normally used to trace the process
logger.info(query);
pstmt = currentCon.prepareStatement(query);
pstmt.executeUpdate();
} catch (Exception ex) {
logger.error("Log In failed: An Exception has occurred! " + ex);
}
/*
*college Registration Bean
*
*
*Version:1.0
*
*Date:2-DEC-2011
*
*/
package com.student.beans;
public class StudentBean {
/**
* Bean class for Student details
*
* @author 533026,533121 version1.0 27/11/2011
*/
// declaring attributes of the student table
private String studentId;
private String studentName;
private int maths;
private int social;
private int hindi;
private int science;
private int english;
private String grade;
public boolean valid;
// getter method for college id
public String getStudentId() {
return studentId;
}
// setter method for college id
public void setStudentId(String newStudentId) {
studentId = newStudentId;
}
// getter method for college name
public String getStudentName() {
return studentName;
}
// setter method for college name
public void setStudentName(String newStudentName) {
studentName = newStudentName;
}
// getter method for college authority
public int getMaths() {
return maths;
}
// setter method for college authority
public void setMaths(int newMaths) {
maths= newMaths;
}
// getter method for college address
public int getSocial() {
return social;
}
// setter method for college address
public void setSocial(int newSocial) {
social = newSocial;
}
// getter method for college address2
public int getHindi() {
return hindi;
}
// setter method for college address2
public void setHindi(int newHindi) {
hindi = newHindi;
}
// getter method for college city
public int getScience() {
return science;
}
// setter method for college city
public void setScience(int newScience) {
science = newScience;
}
// getter method for college state
public int getEnglish() {
return english;
}
// setter method for college state
public void setEnglish(int newEnglish) {
english = newEnglish;
}
// getter method for college state
public String getGrade() {
return grade;
}
// setter method for college state
public void setGrade(String newGrade) {
grade = newGrade;
}
// getter method for is valid
public boolean isValid() {
return valid;
}
// setter method for set valid
public void setValid(boolean newValid) {
valid = newValid;
}
}
package com.student.controllers;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.sql.*;
import com.student.dao.*;
import com.student.beans.*;
import javax.servlet.http.HttpSession;
import org.apache.log4j.Logger;
import org.apache.log4j.PropertyConfigurator;
/**
* Servlet implementation class studentServlet
*/
public class studentServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
static final Logger logger = Logger.getLogger(studentServlet.class);
/**
* Default constructor.
*/
public studentServlet() {
// TODO Auto-generated constructor stub
PropertyConfigurator.configure("log4j.properties");
logger.info("Entered Servlet");
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
doPost(request,response);
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
try
{
HttpSession session = request.getSession(true);
switch (Integer.parseInt(request.getParameter("name"))) {
// case for college registration
case 1:
// creating object to java beans
StudentBean createId = new StudentBean();
createId = CreateIdDAO.register(createId);
// storing the values in variables
logger.info("Entered Case 1:Generation of ID");
session.setAttribute("currentSessionUser", createId);
String destination = "./jsp/studentReport.jsp";
response.sendRedirect(response.encodeRedirectURL(destination));
break;
case 2:
// creating object to java beans
StudentBean registration = (StudentBean)(session.getAttribute("currentSessionUser"));
// storing the values in variables
logger.info("Entered Case 1:College Registration");
registration.getStudentId();
registration.setStudentName(request.getParameter("sn"));
registration.setMaths(Integer.parseInt(request.getParameter("ma")));
registration.setSocial(Integer.parseInt(request.getParameter("so")));
registration.setHindi(Integer.parseInt(request.getParameter("hi")));
registration.setScience(Integer.parseInt(request.getParameter("sc")));
registration.setEnglish(Integer.parseInt(request.getParameter("eng")));
registration = RegistrationDAO.register(registration);
session.setAttribute("currentSessionUser", registration);
String destination1 = "./jsp/collegeReportSuccess.jsp";
response.sendRedirect(response.encodeRedirectURL(destination1));
break;
case 3:
logger.info("Entered Case 2:College Search");
StudentBean user = new StudentBean();
user.setStudentId(request.getParameter("sid"));
user = StudentSearchDao.search(user);
if (user.isValid()) {
session.setAttribute("currentUser", user);
String destination2 = "./jsp/collegeSearchSuccess.jsp";
response.sendRedirect(response
.encodeRedirectURL(destination2)); // logged-in page
} else {
String destination3 = "./jsp/invalidStudentSearch.jsp";
response.sendRedirect(response
.encodeRedirectURL(destination3)); // error page
}
break;
case 4:
logger.info("Entered Case 3:College Deletion");
StudentBean collegeStudent = new StudentBean();
collegeStudent.setStudentId(request.getParameter("sid"));
collegeStudent = DeleteStudentDAO.login(collegeStudent);
session.setAttribute("currentSessionUser", collegeStudent);
response.sendRedirect("./jsp/collegeDeleteSuccess.jsp"); // logged-in
// page
break;
case 5:
logger.info("Entered Case 4:Retreving college details");
StudentBean studentProfile = new StudentBean();
studentProfile.setStudentId(request.getParameter("sid"));
studentProfile = StudentProfileDao.details(studentProfile);
if (studentProfile.isValid()) {
session.setAttribute("current", studentProfile);
String destination2 = "./jsp/updateStudentProfile.jsp";
response.sendRedirect(response
.encodeRedirectURL(destination2));
} else {
String destination2 = "./jsp/InvalidUpdateStudent.jsp";
response.sendRedirect(response
.encodeRedirectURL(destination2));
}
break;
// case for updationg college details
case 6:// creating object to java beans
logger.info("Entered Case 5:Updating college details");
StudentBean update = (StudentBean)(session.getAttribute("current"));
// storing the values in variables
update.setStudentId(update.getStudentId());
update.setStudentName(request.getParameter("sn"));
update.setMaths(Integer.parseInt(request.getParameter("ma")));
update.setSocial(Integer.parseInt(request.getParameter("so")));
update.setHindi(Integer.parseInt(request.getParameter("hi")));
update.setScience(Integer.parseInt(request.getParameter("sc")));
update.setEnglish(Integer.parseInt(request.getParameter("eng")));
update = StudentUpdateDao.register(update);
session.setAttribute("currentUpdateUser", update);
String destination9 = "./jsp/updateStudentSuccess.jsp";
response.sendRedirect(response.encodeRedirectURL(destination9));
break;
}
}catch (Exception e) {
e.printStackTrace();
}
}
}