In our web application we are using servlets,jsp and spring technologies.Here we are also maintaining session mechanism in our application.But now i need to count number of users accessing our web application at a time. How can i implement this mechanism...
View RepliesFor one of my project, required to capture the audit history reports of all the activities of the users within the application.
We are using Servlet/JSP in J2EE environment.
For Ex: Whenever user updates some fields, we need to capture the Old value, new value, user id and time stamp. We have single form with more than 200 fields.
Just want to know the best way to do this..any frameworks available for it...or doing at the database side like using triggers..
I have to design/develop a module in java eg. Login. This module can be accessed by multiple concurrent users say 200, 500, 800 etc.
How such type of modules can be designed in such a way that it can perform successfully.
What are the main concepts at code level / Infrastructure level which we should take care while designing such modules.
Question : What would you do block a user if he fails to login in 3 consecutive attempts ?
My Answer : I will make use of Session object, so that server could identify that all 3 requests came from the same system.
Dont know if i am right .
How is this possible? Here is the servlet page.
/**
* Servlet implementation class InvoicingDeptServlet
*/
@WebServlet("/InvoicingDeptServlet")
public class InvoicingDeptServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
//Make arraylist global object
ArrayList<InvoiceData> invoiceList = new ArrayList<InvoiceData>();
[Code] ....
//read the file
//make the numbers 1 string line
//count the number of repetitiveness in the string for the numbers
//display four lowest ones
import java.io.*;
import java.util.*;
public class Lottery2
[Code] ....
when I run it the array gets sorted but how do i keep the data in other words
what it is supposed to do is grab numbers from a file, and give me the lowest 4 numbers back. I know the numbers using the array but how do i pull out the lowest 4 and keep the data true no matter what numbers or how many of them are in the file.
I need to implement a URL which looks something like below one. The Notable thing is that its only one parameter i need to access and the value that's supposed to be held by the parameter is encrypted which may contains characters like & and =.
Example 1.
www.abc.com/disp?v=qww78agd=
The parameter v in above url contains value qww78agd=.
Supposing the encryption turns out the following way.
Example 2.
www.abc.com/disp?v=qww7&f=iuy68=
www.abc.com/disp?v=qww7&f==iuy68=
Then servlet will take v and f as two separate parameters, whereas i want to obatain qww7&f==iuy68= from parameter.I thought of taking up all key value pairs from request HashMap and concatenating the joints via & and =. But the problem is that two consecutive = signs as in second case of example 2, its treated as only one equal to in request key,value map. Hence, my other = sign(s) are lost.Is there any way such that i can get query string part as it is on my servlet and parse it using string processing on my own?
So I have 2 args[] one that reads the file name in the same directory and the other that tries to count how many of any letter (maybe even words) in the txt file ....
View Replies View RelatedWe have been given an assignment to create a small library, with the following classes Library, Book, Author and Copy. With a given class Biblio which has predefined code and adds the books to the class book in an arraylist in Class Copy.
The UML Domain is attached so you know the flow of the classes Everything is working fine and the generated output is correct.
There is just one method in class Library that is not working, the int method has to count the number of Copy's based on the Class Book (String):
I have to go through the Arraylist in Class Copy and look for a specific book and return the number of copy's.
I have tried multiple steps using a for loop Now I have found a similar post the uses hashset, I have tried below code but the return comes back with 0. (There are 3 copy's)
package domein;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;
import domein.Boek;
import domein.Exemplaar;
[code]....
import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
public class Paragraph {
public static void main(String[] args) throws FileNotFoundException, IOException
[Code] .....
i want to create a program in java which counts the number of prints taken from a printer..
View Replies View RelatedI am using count++ in my program in order to count the number of division that occurs. It works but outputs:
The number of divisions is 1
The number of divisions is 2
The number of divisions is 3
The number of divisions is 4
The number of divisions is 5
All i want is the last line. How do I solve this?
import java.util.Scanner;
public class Program3
{
public static void main(String [] args)
{
int div;
[Code] ....
Given a Numbers instance, whose fields are arrays of all the built-in Java numeric types (int, long, float, double, big-decimal, etc), write a method to sort all the numbers into a master list, and then print out the numbers where the number of digits past the decimal point is equal to the index of the number in the master list.
Is there a function in Java that will give me just the numbers after the decimal? I tried Decimalformat but couldn't get it to work. Here is what I have so far; however, I think I might be on the wrong track.
public class Numbers
{
public static void main(String[] args) {
Byte bNum = new Byte((byte) -50);
Integer iNum = new Integer(168);
Long lNum = new Long(100000L);
Short sNum = new Short((short) 10000);
Float fNum = new Float(12.19f);
Double dNum = new Double(23.123);
BigDecimal bd = new BigDecimal("3.14159265358979323846");
[code]....
So far so good, I need to count the number of rows in a table. What I wrote:
<sql:query dataSource="${statistics}" var="result4">
SELECT COUNT(id) AS count FROM statistics;
</sql:query>
<c:forEach var="row" items="${result4.rows}">
Total players: ${result4.count}
</c:forEach>
But, it doesn't work.
I'm trying to write a program that counts the number of times each number in an array occurs. In theory I understand how it work, you take the first element in the array, compare it again the rest of the array and any time it occurs in the array you increment a counter by 1. Then move onto the next element A[1] and so on...
This is what I've done so far :
public static void main(String[] args) {
int[] array = {5,6,2,5,2,2,0,1,6};
int count = 0;
for(int i = 0; i <array.length; i++) {
int val = array[i];
for(int j = i+1; j<array.length; j++)
[Code] .....
I think I'm on the right track as it correctly prints out the frequency of the first 3 elements, but I'm definitely going wrong somewhere as it just doesn't do it right after that!
I am trying to count the number of occurrences of a string in an array list. I used the following code:
int count = Collections.frequency(strings, search);
strings is the name of the array list and search is the string that I am trying to count the number of occurrences of. My program compiles correctly, but when I enter the string to search for, I get the following error: "Exception in thread "main" java.lang.NullPointerException at java.util.Collections.frquency(Collections.java:37 18)
Why am I getting this error message and how do I fix it?
I need to read the contents of file A, and B and store it in file C by joining the contents of A and B and also counting the number of letters/characters present in it.
I've come up with this so far.
import java.io.FileInputstream;
import java.io.FileNotFoundException;
import java.io.IOException;
public class JavaApplication43{
public static putwrite(string fname) throws FileNotFoundException, IOException
[code]...
I have problems getting the right number of times for each number of the array. Here is my code:
public static void main(String[] args) {
int[] a = { 3, 13, 5, 9, 13, 6, 9, 13, 2, 3 };
int num = 3;
int count = numbers(a, num);
for (int i = 0; i < a.length; i++) {
[Code]...
I have been working on this for hours and cannot get it to work properly. The program is to count the number of characters contained in both strings and display the results. It is also to display the final statement, but only once. This version has a complete statement for each matching character.
import java.util.Scanner;
public class CountMatches {
public static void main(String[] args) {
String firstStr = ("");
String s1 = firstStr;
[Code] ....
I'm attempting to create a program that employs a method to count the number of 7s a user puts as an input into the program. I'm just getting started, but I'm getting an error when I try to implement a main method that says "Illegal start of expression"
What adjustments could I make to eliminate this error message?
// Add a main method here.
public static void main(String[] args) {
//Error occurs here
public static int countSevens(int n) {
// 0. Clean-up. Get rid of any minus signs as that is not a digit.
n = Math.abs(n);
[Code] .....
Write a program using a while-loop (and a for-loop) that asks the user to enter a string, and then asks the user to enter a character. The program should count and display the number of times that the specified character appears in the string. (So, you will have two separate program codes, one using a while-loop and the other one using a for-loop.)
Example:
Enter a string: "Hello, JAVA is my favorite programming language."
Enter a character: e
The number of times the specified character appears in the string: 3
I don't even know where to begin I've only got this
import java.util.Scanner;
public class letterCounter {
public static void main(String [] args) {
Scanner sc = new Scanner(System.in);
System.out.println("Enter a string");
String myString = sc.nextLine();
System.out.println("Enter a letter");
String letter = sc.nextLine();
}
}
IDE: BlueJ
I'm creating a small program to count the number of mouse clicks the user is inputting into a BlankArea for a school assignment. I just finished with making the program look nice and all so I was putting in a MouseListener to detect the clicks. However, when I tried adding a MouseListener to the code, the error in the title appeared.
Java Code:
import javax.swing.*;
import java.awt.*;
import javax.swing.border.*;
import java.awt.event.*;
public class CountClick
{
JTextArea textArea = new JTextArea();
[Code] ....
Here's what's going on:
Compiling causes error as described in Title Java Code: createAndShowGUI() mh_sh_highlight_all('java');
cannot be referenced from a static context appears Java Code: public static void main(String [] args) mh_sh_highlight_all('java');
It contains the thread safe and program previously launched without mouse functionality(program appeared when there were no MouseListener components and thread safe had all static method stuff).
I am trying to flip a coin 1000 times and make the driver class count the number of times a head and tails appear. However, I am having some trouble trying to figure out the error:
package Week5;
import java.util.Random;
public class Coin {
private int heads;
private int tails;
private int face;
[Code] ....
I was able to print out the generated numbers, but java will print either heads or tails a thousand times and count that as 1000 and nil for the other probability...
I have tried running the java application without adding the site to site list in java security tab. But I get a sand box message as APPLICATION BLOCKED BY SECURITY SETTINGS. How to run the java application without adding the site to site list in java security tab.
View Replies View RelatedI am trying to restrict the number of views in JSF 2.0.2 using
<context-param>
<param-name>org.apache.myfaces.NUMBER_OF_VIEWS_IN_SESSION</param-name>
<param-value>5</param-value>
</context-param>
In my case my managed bean is View Scoped and it supports a UI page which has multiple forms and each form is submitted as AJAX POST request.
As per the statndard, setting restriction to 5 should create 5 views and after that based on LRU algorithm the oldest views should get deleted if 6th views is created.
Therefore any action on the oldest view will throw the ViewExpiredException and i simply redirect the user to view expired page.
1) When i set the restriction to 5 views, i open 4 tabs with 3 forms each.
2) I submit the 3 forms on first tab everything works fine.
3) As soon as I go to 2nd tab and submit the first form thr, i get view expired exception
4) It seems I am exceeding the number of views I mentioned in web.xml
I want to know :
1) Does every AJAX POST submit itself creates a view ?
2) How I can count the number of views created in a session ?
3)Can i force expiry of a view in JSF 2.0.2 while the session is still alive ?
4) Normally JSF 2.0.2 session cachces the views. Lets assume session is alive the entire day but a view was created in morning at 9:00 AM and is not used again the entire day. Assuming that session doesn't reaches the max number of views it can save in entire day, will the view created in morning expire on its own after certain interval of time ? If not , can we still force its expiry while keeping the session alive ?
I have an array with the following characters {'E', 'L','E','P','H','A','N','T','P','O'}
now, I need an array that will store the first array such that only the occurence occurs e.g {'E','L','P','H','A','N','T','O'} Notice that the characters 'E' and 'P' occur twice and as a result were not repeated the second time in the new array.
How would one go about this using the counting elements technique?
I tried this but not sure how to use the counting elements technique.
char [] arr = new char{'E', 'L','E','P','H','A','N','T','P','O'};
char[] bucket = new char[(arr[0] * arr.length)];
for (int i = 0; i < len; i++)
bucket[arr[i]]++;