I am beginner in JSP and Servlets. I have searched about the issue and couldn't found exactly what the solution is.
I am passing data from jsp to servlet and inserting in database and from there retrieving the same and passing to JSP for display
I was able to pass data from JSP and insert in database successfully but unable to retrieve and display in jsp again. Below is code.
jsp:
<!DOCTYPE HTML><%#page language="java"
contentType="text/html; charset=ISO-8859-1" pageEncoding="ISO-8859-1"%>
<html>
<head>
<title>loginform</title>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
</head>
<body>
<form name=loginform action=TestServlet method=post>
Input ID <input type=text name="id" size=10></input> <br><br>
<Input type="button" value=Retrive> <br>
<label for = "getdata" ></label> <br>
value is <%= request.getSession().getAttribute("data") %>
<input type=submit value=submit></input>
</form>
</body>
</html>
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 javax.servlet.http.HttpSession;
import java.sql.*;
/**
* Servlet implementation class TestServlet
*/
public class TestServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* #see HttpServlet#HttpServlet()
*/
public TestServlet() {
super();
// TODO Auto-generated constructor stub
}
/**
* #see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
}
/**
* #see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
response.setContentType("text/html");
// Actual logic goes here.
try {
String getvalue=request.getParameter("id");
PrintWriter out = response.getWriter();
out.println(getvalue);
out.println("attempting to read from table");
Class.forName("oracle.jdbc.driver.OracleDriver");
// Open a connection
Connection conn = DriverManager.getConnection("jdbc:oracle:thin:#IP:Port:ServiceName, UN, Pass);
// Execute SQL query
Statement stmt = conn.createStatement();
String sqlinsert, sqlselect;
sqlinsert = "Insert into abc(abc) values("+getvalue+")";
sqlselect="Select abc from abc";
ResultSet rs = stmt.executeQuery(sqlinsert);
ResultSet rs1 = stmt.executeQuery(sqlselect);
int id=0 ;
// Extract data from result set
while(rs1.next()){
//Retrieve by column name
id = rs1.getInt("ABC");
//Display values
out.println("ID: " + id + "<br>");
}
HttpSession session = request.getSession(false);
request.setAttribute("data", "0");
request.getRequestDispatcher("/loginform.jsp").forward(request, response);
// out.println("</body></html>");
// Clean-up environment
rs.close();
stmt.close();
conn.close();
}catch(SQLException se){
//Handle errors for JDBC
se.printStackTrace();
}catch(Exception e){
//Handle errors for Class.forName
e.printStackTrace();
}
}
}
I am unable to understand where is the problem. Every time I run the code I am able to see only null in JSP.
Simply change request.getSession().getAttribute("data") to request.getAttribute("data") and it will work fine.
In your Java code you use request.setAttribute("data", "0"); ,but in you JSP page you use request.getSession().getAttribute("data") ,so you will not get the data.
you are actually storing your data in session and try to fetch it from request scope so i think you are getting null value.
in jsp remove <%= request.getSession().getAttribute("data") %> line and use this line <%= request.getAttribute("data") %>
Related
I am trying to make a login form. and want the username parameter to accessed by the changepass.java file.
The flow of the application is:
login.jsp -> LoginServlet -> AfterLogin.jsp -> ChangePass.jsp -> ChangePassword Servlet
I tried using the session and request dispatcher for this it is not working.
I am able to get the parameter from login.jsp to ChangePass.jsp but after that the changePassword servlet is not able to access it.
My code for the flow is:
login.jsp
<%# page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="ISO-8859-1">
<title>Insert title here</title>
</head>
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.4.1/css/bootstrap.min.css" integrity="sha384-Vkoo8x4CGsO3+Hhxv8T/Q5PaXtkKtu6ug5TOeNV6gBiFeWPGFN9MuhOf23Q9Ifjh" crossorigin="anonymous">
<body>
<div align="center">
<form name="login" onsubmit="return onSubmit()" action="LoginServlet">
<h2 style="color:blue">Account Login</h2>
<table style="background-color:powderblue;border: 2px solid green;border-color:green;">
<tr><td>Enter User Name:</td><td><input type="text" name="username" minlength="6" required></td></tr>
<tr><td>Enter Pass Word:</td><td><input type="password" name="password" id="password" required></td></tr>
<tr><td colspan="2" align="center"><input type="submit" value="login"></td></tr>
</table>
<br>
<u>Home</u>
</form>
</div>
<%
String msg=(String) request.getAttribute("msg");
if(msg!=null){
%>
<p style="color:red"><%=msg%></p>
<%
}
%>
<script type="text/javascript">
function onSubmit(){
var y=document.login.password.value;
var passR=/^(?=.*\d)(?=.*[A-Z]).{6,20}$/;
if(!y.match(passR)){
alert("Password must contain at least one number and one UpperCase letter");
document.getElementById("password").focus();
}
}
</script>
</body>
</html>
LoginServlet.java
package com.wipro.controller;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import com.wipro.util.DButil;
/**
* Servlet implementation class LoginServlet
*/
#WebServlet("/LoginServlet")
public class LoginServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* #see HttpServlet#HttpServlet()
*/
public LoginServlet() {
super();
// TODO Auto-generated constructor stub
}
/**
* #see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
try{
Connection con=DButil.getConnection();
PrintWriter out=response.getWriter();
String username=request.getParameter("username");
String password=request.getParameter("password");
String sql="select * from user_table where username=? and password=?";
PreparedStatement st=con.prepareStatement(sql);
st.setString(1, username);
st.setString(2, password);
ResultSet rs=st.executeQuery();
if(rs.next()) {
HttpSession se=request.getSession();
se.setAttribute("username", username );
request.getRequestDispatcher("AfterLogin.jsp").include(request, response);
}
else {
request.setAttribute("msg", "Invalid Credentials");
request.getRequestDispatcher("login.jsp").include(request, response);
}
}
catch(Exception e) {
e.printStackTrace();
}
}
/**
* #see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
doGet(request, response);
}
}
AfterLogin.jsp
<%# page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
<h1><font color=green> Welcome <%=session.getAttribute("username")%></font></h1>
Change Password
</body>
</html>
ChangePass.jsp
<%# page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
<div align="center">
<form name="changePS" onsubmit="return onSubmit()" action="ChangePassword">
<%
String username=(String)session.getAttribute("username");
request.setAttribute("username", username);
%>
<h1><font color=green> Welcome <%=username%></font></h1>
<h2 style="color:blue">Change Password</h2>
<table style="background-color:powderblue;border: 2px solid green;border-color:green;">
<tr><td>Old Password:</td><td><input type="password" name="oldpwd" id="oldpwd" required></td></tr>
<tr><td>New Password:</td><td><input type="password" name="newpwd" id="newpwd" required></td></tr>
<tr><td>Confirm Password:</td><td><input type="password" name="confpwd" id="confpwd" required></td></tr>
<tr><td colspan="2" align="center"><input type="submit" value="login"></td></tr>
</table>
<br>
<u>Home</u>
</form>
</div>
<script type="text/javascript">
function onSubmit(){
y=document.changePS.oldpwd.value;
z=document.changePS.newpwd.value;
a=document.changePS.confpwd.value;
passR=/^(?=.*\d)(?=.*[A-Z]).{6,20}$/;
if(z != a){
alert("New Password and Confirm Password do not match");
document.getElementById("confpwd").focus();
return false;
}
if(!y.match(passR)){
alert("Old Password must contain at least one number,one UpperCase letters");
document.getElementById("oldpwd").focus();
return false;
}
if(!z.match(passR)){
alert("New Password must contain at least one number,one UpperCase letters");
document.getElementById("newpwd").focus();
return false;
}
return true;
}
</body>
</html>
ChangePassword.java
package com.wipro.controller;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.PreparedStatement;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import com.wipro.util.DButil;
/**
* Servlet implementation class ChangePassword
*/
#WebServlet("/ChangePassword")
public class ChangePassword extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* #see HttpServlet#HttpServlet()
*/
public ChangePassword() {
super();
// TODO Auto-generated constructor stub
}
/**
* #see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
try{
Connection con=DButil.getConnection();
PrintWriter out=response.getWriter();
String username = (String)request.getAttribute("username");
String password=request.getParameter("newPwd");
String sql="update user_table set password=? where username=?";
PreparedStatement st=con.prepareStatement(sql);
st.setString(1, username);
st.setString(2, password);
int rs=st.executeUpdate();
if(rs!=0) {
out.println("<h1><font color=green> Updated the password </font></h1>");
}
else {
out.println("<h1><font color=red> Sorry no username with this name </font></h1>"+username);
}
}
catch(Exception e) {
e.printStackTrace();
}
}
/**
* #see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
doGet(request, response);
}
}
I am developing a small sql servlet application that takes in a SQL command from a text area in an html page, sends the command to a servlet that makes an sql connection and puts in the resultset into an arraylist. I have all of that down, and i can print column names to the browser in the java servlet class. One thing i need to do is print the results into a table using a JSP page. The JSP page will look just like the html page we first used. I can not figure out how i am going to get the arraylist from the servlet to the JSP page to be displayed to the user.
Here is the HTML page:
<html>
<head>
<title>WebApp</title>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
</head>
<body style="background-color:blue;">
<center>
<font color="white">
<h1> Welcome to the Project 4 Remote Database Management System</h1>
<hr>
You are connected to the Project4 database. <br>Please enter any valid SQL query or update statement.<br>
If no query/update command is given the Execute button will display all supplier information in the database. <br>All execution results will appear below.
<br>
<br>
<form action="NewServlet" method="post">
<textarea rows="10" cols="60"name="command"></textarea>
<br>
<button type="submit">Execute Query</button>
<button type="submit">Clear Command</button>
</form>
<hr>
<h1>Database Results</h1>
</font>
</body>
</html>
and here is the servlet code:
import java.io.IOException;
import java.io.PrintWriter;
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.Vector;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.swing.JOptionPane;
/**
*
* #author KJ4CC
*/
public class NewServlet extends HttpServlet {
/**
* Processes requests for both HTTP <code>GET</code> and <code>POST</code>
* methods.
*
* #param request servlet request
* #param response servlet response
* #throws ServletException if a servlet-specific error occurs
* #throws IOException if an I/O error occurs
*/
Connection connection;
Vector<String> columnNames = new Vector<String>();
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html;charset=UTF-8");
try (PrintWriter out = response.getWriter()) {
/* TODO output your page here. You may use following sample code. */
String command = request.getParameter("command");
out.println("<!DOCTYPE html>");
out.println("<html>");
sqlConnection(command);
//prints out column names into the browser.
out.println(columnNames);
}
}
public void sqlConnection(String command){
String driver = "com.mysql.jdbc.Driver";
String url = "jdbc:mysql://localhost:3306/project3";
String user = "root";
String pass = "Brandy?1994";
ResultSet rs;
try {
Class.forName(driver);
} catch (ClassNotFoundException ex) {
Logger.getLogger(NewServlet.class.getName()).log(Level.SEVERE, null, ex);
}
try {
connection = DriverManager.getConnection(url,user,pass);
} catch (SQLException ex) {
Logger.getLogger(NewServlet.class.getName()).log(Level.SEVERE, null, ex);
}
Statement stmt;
try {
stmt = connection.createStatement();
rs = stmt.executeQuery(command);
int colNum = rs.getMetaData().getColumnCount();
for (int i = 0; i < colNum; i++) {
columnNames.add(rs.getMetaData().getColumnLabel(i+1));
}
} catch (SQLException ex) {
Logger.getLogger(NewServlet.class.getName()).log(Level.SEVERE, null, ex);
}
}
// <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
/**
* Handles the HTTP <code>GET</code> method.
*
* #param request servlet request
* #param response servlet response
* #throws ServletException if a servlet-specific error occurs
* #throws IOException if an I/O error occurs
*/
#Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
/**
* Handles the HTTP <code>POST</code> method.
*
* #param request servlet request
* #param response servlet response
* #throws ServletException if a servlet-specific error occurs
* #throws IOException if an I/O error occurs
*/
#Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
/**
* Returns a short description of the servlet.
*
* #return a String containing servlet description
*/
#Override
public String getServletInfo() {
return "Short description";
}// </editor-fold>
}
Here is the start of the JSP page:
<html>
<head>
<title>WebApp</title>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
</head>
<body style="background-color:blue;">
<center>
<font color="white">
<h1> Welcome to the Project 4 Remote Database Management System</h1>
<hr>
You are connected to the Project4 database. <br>Please enter any valid SQL query or update statement.<br>
If no query/update command is given the Execute button will display all supplier information in the database. <br>All execution results will appear below.
<br>
<br>
<form action="NewServlet" method="post">
<textarea rows="10" cols="60"name="command"></textarea>
<br>
<button type="submit">Execute Query</button>
<button type="submit">Clear Command</button>
</form>
<hr>
<h1>Database Results</h1>
<%
DO TABLE STUFF HERE TO OUTPUT SQL RESULTS
%>
</font>
</body>
</html>
I think i will create a javaBean to store the arrays so that the JSP page can access the column arraylist. Then use a for loop to iterate through the array list so that i can create the table columns. how could i link the JSP page to the servlet so that if can get the information needed?
I have to do the sql connection in the servlet and cannnot make the connection in the JSP page.
In your servlet method, set attribute in page context as below
HttpServletRequest req = (HttpServletRequest)request;
.... // find out what to put
req.getPageContext.setAttribute('some', objectYouFound);
In your jsp, use el to access the variable:
${some}
In the servlet, store the data in a request attribute:
request.setAttribute("rows", rows);
In the JSP, use the JSTL to loop over the rows:
<c:forEach var="row" value="${rows}">
...
</c:forEach>
Do NOT use Java scriptlets in your JSP.
You have few issues with your current code:
(1) A single servlet instance will be shared across all request threads, so you should NOT create the instance variables for a servlet class i.e.,
Connection connection;
Vector<String> columnNames = new Vector<String>();
These two variables should be created inside your processRequest() method so that they will be local to each request thread.
(2) You are ONLY querying the META DATA of the table, so you can display only column names, but if you wanted to fetch the data as well, you need to use resultSetObj.hasNext() and then use next() method like below:
while (rs.hasNext())
{
String X = rs.getString("empno");
//Retrieve all data
//add to a bean object
//add to list
}
//Now return the list which contains the data
You can look at here for a good example.
(3) Use the request.setAttribute to set the results to the request object and then you can retrieve to the next JSP (results) page.
I am trying to add or insert values into table of database using servlet and jsp and MySQL Workbench as database. These are the following details:
1.> Register.java
package register.com;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.sql.*;
import javax.servlet.*;
/**
* Servlet implementation class Register
*/
#WebServlet("/register")
public class Register extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* #see HttpServlet#HttpServlet()
*/
public Register() {
super();
// TODO Auto-generated constructor stub
}
/**
* #see Servlet#init(ServletConfig)
*/
public void init(ServletConfig config) throws ServletException {
// TODO Auto-generated method stub
}
/**
* #see HttpServlet#service(HttpServletRequest request, HttpServletResponse response)
*/
protected void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
}
/**
* #see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
}
/**
* #see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
response.setContentType("text/html");
PrintWriter pw = response.getWriter();
//String connectionURL = "jdbc:mysql://127.0.0.1:3306/newData";// newData is the database
//Connection connection;
Connection conn=null;
String url="jdbc:mysql://localhost:3306/";
String dbName="userlogindb";
String driver="com.mysql.jdbc.Driver";
//String dbUserName="root";
//String dbPassword="root";
try{
String Fname = request.getParameter("fname");
String Mname = request.getParameter("mname");
String Lname = request.getParameter("lname");
String Uname = request.getParameter("username");
String Emailid = request.getParameter("emailid");
String Mobno = request.getParameter("mobno");
String Address = request.getParameter("address");
String Password1 = request.getParameter("password1");
String Password2 = request.getParameter("password2");
Class.forName(driver).newInstance();
conn = DriverManager.getConnection(url+dbName,"root", "root");
PreparedStatement pst =(PreparedStatement) conn.prepareStatement("insert into 'userlogindb'.'registerutable'(fname,mname,lname,username,emailid,mobno,address,password1,password2) values(?,?,?,?,?,?,?,?,?)");//try2 is the name of the table
pst.setString(1,Fname);
pst.setString(2,Mname);
pst.setString(3,Lname);
pst.setString(4,Uname);
pst.setString(5,Emailid);
pst.setString(6,Mobno);
pst.setString(7,Address);
pst.setString(8,Password1);
pst.setString(9,Password2);
int i = pst.executeUpdate();
conn.commit();
String msg=" ";
if(i!=0){
msg="Record has been inserted";
pw.println("<font size='6' color=blue>" + msg + "</font>");
}
else{
msg="failed to insert the data";
pw.println("<font size='6' color=blue>" + msg + "</font>");
}
pst.close();
}
catch (Exception e){
pw.println(e);
}
}
}
2.> index.jsp
<%# page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
<form name="registrationform" action="register" method="post">
<p>
Enter your first name: <input type="text" name="fname"><br>
Enter your middle name: <input type="text" name="mname"><br>
Enter your last name: <input type="text" name="lname"><br>
</p><br>
<p>
Enter username: <input type="text" name="username"><br>
</p><br>
<p>
Enter email id: <input type="text" name="emailid"><br>
Enter mobile number: <input type="text" name="mobno"><br>
Enter address: <textarea rows="5" cols="5" name="address"></textarea><br>
</p><br>
<p>
Enter the password: <input type="password" name="password1"><br>
Reenter the password: <input type="password" name="password2"><br>
</p><br>
<p>
<input type="submit">
</p><br>
</form>
</body>
</html>
3.> web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
<display-name>RegisterExample</display-name>
<welcome-file-list>
<welcome-file>index.html</welcome-file>
<welcome-file>index.htm</welcome-file>
<welcome-file>index.jsp</welcome-file>
<welcome-file>default.html</welcome-file>
<welcome-file>default.htm</welcome-file>
<welcome-file>default.jsp</welcome-file>
</welcome-file-list>
<servlet>
<description>Register Servlet</description>
<display-name>Register</display-name>
<servlet-name>Register</servlet-name>
<servlet-class>register.com.Register</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>Register</servlet-name>
<url-pattern>/register</url-pattern>
</servlet-mapping>
</web-app>
4.> I have added mysql-connector-java-5.0.8-bin.jar and servlet-api-3.0.jar is anything else needed to add it. I have created a connection to database in Data Source Explorer.
When I m compiling or debuging it shows no error. During runtime also there is no error.
When I fill in the form and submit it shows only blank screen :(
No output is displayed. :(
Also in the database values are not updated.
Please help me. I m getting hangover with this snippet.
Check that doPost() method of servlet is called from the jsp form and remove conn.commit.
Can you check value of i by putting logger or println(). and check with closing db conn at the end. Rest your code looks fine and it should work.
Same problem fetch main problem in PreparedStatement use simple statement then you successfully insert record same use below.
String st2="insert into
user(gender,name,address,telephone,fax,email,
destination,sdate,edate,Participant,hcategory,
Culture,Nature,People,Cities,Beaches,Festivals,username,password)
values('"+gender+"','"+name+"','"+address+"','"+phone+"','"+fax+"',
'"+email+"','"+desti+"','"+sdate+"','"+edate+"','"+parti+"',
'"+hotel+"','"+chk1+"','"+chk2+"','"+chk3+"','"+chk4+"',
'"+chk5+"','"+chk6+"','"+user+"','"+password+"')";
int i=stm.executeUpdate(st2);
In your JSP at line <form> tag,
try this code
<form name="registrationform" action="Register" method="post">
String user = request.getParameter("uname");
out.println(user);
String pass = request.getParameter("pass");
out.println(pass);
Class.forName( "com.mysql.jdbc.Driver" );
Connection conn = DriverManager.getConnection( "jdbc:mysql://localhost:3306/rental","root","root" ) ;
out.println("hello");
Statement st = conn.createStatement();
String sql = "insert into login (user,pass) values('" + user + "','" + pass + "')";
st.executeUpdate(sql);
Remove conn.commit from Register.java
In your jsp change action to :<form name="registrationform" action="Register" method="post">
I had a similar issue and was able to resolve it by identifying which JDBC driver I intended to use. In my case, I was connecting to an Oracle database. I placed the following statement, prior to creating the connection variable.
DriverManager.registerDriver( new oracle.jdbc.driver.OracleDriver());
I am newbie here. I have an assignment that requires to connect mysql, servlet and java (because i want to separate java code and html code. Previously, i combined the codes to make it easier and was rejected)
So, basically, in mySql i write this,
create table login2 (username varchar (30), password varchar(30), designation varchar(10));
insert into login2 values('lala','123','A');
and i create loginDisp.java in the servlet using eclipse. This is my command
package Servlet;
import java.io.*;
import java.util.*;
import javax.sql.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class loginDisp extends HttpServlet {
public void service(HttpServletRequest request,
HttpServletResponse response)
throws IOException, ServletException{
// String username=request.getParameter("Username");
// String password=request.getParameter("Password");
response.setContentType("text/html");
PrintWriter out = response.getWriter();
out.println("<html>");
out.println("<head><title>Servlet JDBC</title></head>");
out.println("<body>");
out.println("<h1>Servlet JDBC</h1>");
out.println("</body></html>");
// connecting to database
Connection con = null;
Statement stmt = null;
ResultSet rs = null;
try {
Class.forName("com.mysql.jdbc.Driver");
con =DriverManager.getConnection
("url/tablename","uname","pssword");
stmt = con.createStatement();
rs = stmt.executeQuery("SELECT * FROM login2");
// displaying records
while(rs.next()){
out.print(rs.getObject(1).toString());
out.print("\t\t\t");
out.print(rs.getObject(2).toString());
out.print("<br>");
}
} catch (SQLException e) {
throw new ServletException("Servlet Could not display records.", e);
} catch (ClassNotFoundException e) {
throw new ServletException("JDBC Driver not found.", e);
} finally {
try {
if(rs != null) {
rs.close();
rs = null;
}
if(stmt != null) {
stmt.close();
stmt = null;
}
if(con != null) {
con.close();
con = null;
}
} catch (SQLException e) {}
}
out.close();
}
}
When i execute, it is well displayed. Hence, i started to make the Login.jsp as i want to make a text.box for user to insert username and password. This is my code
<%# page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
<body>
<center>
<div class="wrapper">
<br>
<br>
<h2>Doctor</h2>
<form name="form1" method="post" action="loginDisp" > <!-- onsubmit="return validateForm()" -->
<table width="326" border="1" align="center">
<center> <tr>
<th width="138" scope="row">Username</th>
<td width="142"><input type="text" name="Username"></td>
</tr>
</center>
<tr>
<th height="31" style="width: 162px;"><span class="style2">Password</span>
</th>
<td width="142"><input type="password" name="Password"></td>
</tr>
<tr>
</tr>
</table>
<p align="center">
<input type="submit" name="Submit" value="Submit">
</p> ${message}
</form>
</div>
</center>
</body>
</body>
</html>
and I get the data from mySQL displayed. I add another log.java in servlet because i thought when we need a data fetched from jsp to databased and displayed when be called. This is code in log.java
package Servlet;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class log extends HttpServlet {
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
//Get username and password from the JSP page
String username=request.getParameter("Username");
String password=request.getParameter("Password");
//Print the above got values in console
System.out.println("The username is" +username);
System.out.println("\nand the password is" +password);
}
}
The username and password inserted in login.jsp does not inserted automatically in mySQL, hence when i try to executed loginDisp.java , it will display only the data i inserted manually in mySQL.
You can not use the java file name as action this is defined in the web.xml file and there is servlet mapping and you can use
<servlet>
<servlet-name>log</servlet-name>
<servlet-class>loginDisplay</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>log</servlet-name>
<url-pattern>/loginDisplay</url-pattern>
</servlet-mapping>
and now you can use the action = "loginDisplay" in the action tag and by using this
I hope you did not face the problem of 404 error.
You entered a wrong action in form.
Since form's action attribute takes the path of the servlet you should give the relavent mapping specified in web.xml
action="loginDisplay.java"
should be action="/loginDisplay"
<form name="form1" method="post" action="loginDisplay.java" onsubmit="return validateForm()">
It should be
<form name="form1" method="post" action="/loginDisplay" onsubmit="return validateForm()">
If /loginDisplay is not the exact mapping in your web.xml check the web.xml file and see the mapping for loginDisplay and give that path as action.
A quick example
Create a new package (called dao or model) where you put your logic to access to the DB.
Then create a Java Bean Object where store the results of your DB and instanciate your class of the logic in the servlet, then access to the properties of the Bean and show it in the WEB.
package model:
class DaoAccess (methods to connect with DB)
class Login (properties of the table with getXXX and setXXX of each one)
package Servlet.
class loginDisplay:
public class loginDisplay extends HttpServlet {
public void service(HttpServletRequest request, HttpServletResponse response)
throws IOException, ServletException {
response.setContentType("text/html");
PrintWriter out = response.getWriter();
out.println("<html>");
out.println("<head><title>Servlet JDBC</title></head>");
out.println("<body>");
out.println("<h1>loginDisplay</h1>");
out.println("</body></html>");
// connecting to database
Connection con = null;
Statement stmt = null;
ResultSet rs = null;
DaoAccess dao = new DaoAccess();
List<Login> list = dao.readAll();
for(Login obj: list){
out.write(obj.getName());
out.write(obj.getPassword());
}
out.close();
}
}
I have a query that is being used to pull usernames and info about the user. In Access I had the LIKE function so that the user didn't have to type in a specific name. I am now transferring it over to JSP. Here is the line in the query that I am having troubles with in JSP:
WHERE ObjectName Like '" + "%"+ VariableName + "%" +"';
The query runs fine but does not show any information even if I put in the entire name. If I change it to:
WHERE ObjectName = '" + VariableName +"';
it works, but I would like to give the user a chance to have to ability to put in partial names in case they do not know how to spell the name or typ eit incorrectly. Any help would be apprecited.
Thanks
The line you've shown is a bit odd, but syntactically valid. So the problem lies somewhere else. What does variableName actually contain?
That said, you shouldn't be writing raw Java code in JSP files. Do that in a Java class. You can use a Servlet class to preprocess or postprocess requests. Also grab PreparedStatement to avoid SQL injections. Here's a kickoff example:
public List<User> search(String username) throws SQLException {
Connection connection = null;
PreparedStatement statement = null;
ResultSet resultSet = null;
List<User> users = new ArrayList<User>();
try {
connection = database.getConnection();
statement = connection.prepareStatement("SELECT id, username, age, email FROM user WHERE username LIKE ?");
statement.setString(1, "%" + username + "%");
resultSet = statement.executeQuery();
while (resultSet.next()) {
users.add(mapUser(resultSet));
}
} finally {
close(connection, statement, resultSet);
}
return users;
}
Avoid writing SQL queries in JSP
"SELECT * FROM something WHERE ObectName LIKE '%" + VariableName + "%'" should work
this is an answer for starting users
i am created a data base in a name ASHRAF, then i create a table in name CASH. the code is given below
CREATE TABLE CASH(NO INT NOT NULL PRIMARY KEY AUTO_INCREMENT,NAME VARCHAR(50) NOT NULL,ADDRESS VARCHAR(100),PET_NAME VARCHAR(50),PLACE VARCHAR(50),TYPE VARCHAR(20),TYPE_OF_PAY VARCHAR(20),AMOUNT INT(6) NOT NULL);
here the NO is auto increment ant it is primary key anyway you can search the contents from the table using jsp code that i given below
am search here using both NAME ADDRESS you can pass the parameters using a html page and a servlet
The html page(show.html) that i created is given below
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>show.html</title>
</head>
<body>
<h1><b><font color=020202>SHOW</font></b></h1><br><br>
<form name="f6" action="getshow" method="POST" onsubmit="return check(this)">
<table border="0">
<tr>
<td>Name :</td><td><input type="text" name="name"></td>
</tr>
<tr>
<td>House Name :</td><td><input type="text" name="address"></td>
</tr>
<tr>
<td><br><input type="SUBMIT" value="submit"></td>
</tr>
</table>
</form>
</body>
</html>
The servlet is(getshow.java) given below
package Servlets;
import java.io.IOException;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* Servlet implementation class getdata
*/
public class getshow extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* #see HttpServlet#HttpServlet()
*/
public getshow() {
super();
// TODO Auto-generated constructor stub
}
/**
* #see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response)
`` throws ServletException, IOException {
// TODO Auto-generated method stub
}
/**`
* #see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse
``response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
try{
String url=null;
String s1=request.getParameter("name");
String s2=request.getParameter("address");
request.setAttribute("name",s1);
request.setAttribute("address",s2);
url="show.jsp";
RequestDispatcher view=request.getRequestDispatcher(url);
view.forward(request, response);
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
The jsp file is(show.jsp) given below
<%# page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>`
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>show.jsp</title>
</head>
<body>
<%String aid=(String)request.getAttribute("name"); %>
<%String sid=(String)request.getAttribute("address"); %>
<%
Connection con=null;
ResultSet rs=null;
String records=null;
StringBuffer appender=new StringBuffer();
java.sql.PreparedStatement st=null;
try {
Class.forName("com.mysql.jdbc.Driver").newInstance();
con=DriverManager.getConnection("jdbc:mysql://localhost/ASHRAF?user=root&password=password");
st=con.prepareStatement("select *from CASH where NAME like '" + aid + "%" +"' and ADDRESS like '" + sid + "%" +"'");
rs=st.executeQuery();
%>
<center><TABLE cellpadding="15" border="2">
<TR>
<TH>NO</TH>
<TH>NAME</TH>
<TH>HOUSE NAME</TH>
<TH>PET NAME</TH>
<TH>PLACE</TH>
<TH>TYPE OF OCCATION</TH>
<TH>TYPE OF PAY</TH>
<TH>AMOUNT</TH>
</TR>
<%
while (rs.next()) {
%>
<TR>
<TD><%=rs.getString(1)%></TD>
<TD><%=rs.getString(2)%></TD>
<TD><%=rs.getString(3)%></TD>
<TD><%=rs.getString(4)%></TD>
<TD><%=rs.getString(5)%></TD>
<TD><%=rs.getString(6)%></TD>
<TD><%=rs.getString(7)%></TD>
<TD><%=rs.getString(8)%></TD>
</TR>
<% } %>
</TABLE>
</center>
</div>
<%
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
finally
{
try {
con.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
} %>
</body>
</html>
now you can search either with the name nor with the address or with both.