I have a matrix int[][] and I want it to be accessible to all jsp files.
The code is:
int[][] matrix = methodThatGeneratesTheMatrix;
How can I access/use this matrix in all jsp files?
I have index.jsp in that page logout is available. while hitting the button . i want to invalidate all the session variable which i used. but it is not happening.
<html:image src="/x/images/logout1.png" onclick="logout()"> </html:image><script type="text/javascript">
function logout() {
document.forms[0].action = "/x/x.do?method=dologout";
document.forms[0].submit();
[Code] .....
Even when i logout. then i start from new session means., session values continues from previous session. not killed.
i have some jsps under WEB-INF folder and as i know that they cant be access directly. so how can i access those jsps.
View Replies View RelatedI need to access and view files/foldersand if possible i can download from shared folder from other system using java
View Replies View RelatedI'm trying to acces my variable "cost" so when i press a button it prints the cost(for now) but the int value just prints 0
public class Holiday extends JFrame
{
private RoutinePanel routine; // A panel for routine charge checkboxes
private JPanel HolidayPanel; // A panel for non-routine charges
[Code].....
why I cant access a variable from another class, in particular why in the main class cant i assign " quiz1 = getQuizOne();" ? It constantly giving me error.
Java Code:
import java.util.Scanner;
public class Grade {
private int quiz1, quiz2, midtermExam, finalExam = 0;
public static void main(String[] args)
{
Student John = new Student();
John.StudentData();
[code]....
Java Code:
public class MountainBike extends Bicycle {
// the MountainBike subclass has
// one field
public int seatHeight;
// the MountainBike subclass has
// one constructor
public MountainBike(int startHeight, int startCadence,
[Code] ....
At first,
Java Code: public int seatHeight; mh_sh_highlight_all('java');
tells us that seatHeight is NOT a static field (because of the absence of static keyword).
Whereas in the constructor, the absence of dot notation (like something like this.seatHeight) in
Java Code: seatHeight = newValue; mh_sh_highlight_all('java');
shows that it IS a non-member/static variable.
How does this make sense?
I want to access variable of java file into jsp Page. So I tried to do this but it does not work.
Problem : when I am trying to access "getName" method of java class into jsp file it displaying error, i already imported "Ajaxmethod.java" file in to "success.jsp" I want to access "getName" method in to jsp file without creating object of class.
Ajaxmethod.java
package a.b;
public class Ajaxmethod implements Action{
public String name;
public String getName() {
return name;
}
[Code]...
how to get an access to the method with a parameter of class type variable, lets say: public void insert(Record newRecord, int pos)?
View Replies View Relatedjava program that will determine if the matrix is a lower or upper triangular matrix. I only need to use java.util.Scanner;.
View Replies View RelatedI am currently building a Plugin system for an application and I wanted to add a little security feature.
I have read many tutorials on this and they basically all came down to the same answer:
"Its complicated: You need a custom class loader and security manager and ... and even then its still tricky"
So I thought, before I load the classes dynamically I will simply read the class files. Why bother with a SecurityManager or ClassLoader if I can simply whitelist all allowed classes and search for all illegal Class access before I even load anything.
I'm getting an error on line 137 and all it is rsmd = rs.getMetaData();The error happens only after I press a JButton and it is
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerExceptionat softwareDesign.createAccount.actionPerformed(createAccount.java:137)
There is a lot more to it but that has nothing to do with my code it's just the stuff with Eclipse anyway I want to know how do I fix this problem?
What step to know to develop software..
View Replies View RelatedGiven the case I have an object which is assigned only once. What is the difference in doing:
public class MyClass {
private MyObj obj = new MyObj("Hello world");
private MyClass(){}
//...
}
and
public class MyClass {
private MyObj obj;
private MyClass(){
obj = new MyObj("Hello world");
}
//...
}
Is there a difference in performance or usability? (Given also the case there are no static calls expected) ....
The term "Local variable" is related to scope. That is a local variable is one which is defined in a certain block of code, and its scope is confined inside that block of code.And a "Member variable" is simple an instance variable.
I read in a discussion forum that when local variables are declared (example code below), their name reservation takes place in memory but they are not automatically initialized to anything. On the other hand, when member variables are declared, they are automatically initialized to null by default.
Java Code: public void myFunction () {
int [] myInt; // A local, member variable (because "static" keyword is not there) declared
} mh_sh_highlight_all('java');
So it seems that they are comparing local variables and member variables. While I think a member variable can also be be local in a block of code, isn't it?
In a program I created, I'm using a text file that contains some texts needed for the program. The method relevant to this is something like the following.
private String wordgen(){
try {
BufferedReader reader = new BufferedReader(new FileReader("src/Resources/adjectives.txt"));
Random rand = new Random();
int low = rand.nextInt(400);
String fil="";
int i=0;
while(i!=low){
[Code]...
The program runs fine in netbeans project but once the jar is created it does not corporate with the text file. ("null" is returned) How can I attach text files to jar and exe?
Given a reference variable : Car c1 = new Car();
when we create another variable and set it equal to the first : Car c2 = c1;
we're pointing c2 at the same car object that c1 points to (as opposed to pointing c2 at c1, which in turn points at the car). So if we have code like,
Car c1 = new Car();
Car[] cA = {c1, c1, c1, c1};
are we doing the same? Are we creating four *new* reference variables, each of which points at the same car (again as opposed to pointing them at c1 itself)? I think so, but want to make sure I'm understanding this correctly.
Im trying to get the user to input the rows one by one but my input stops after the first. the examples i looked at in my book had this way i used as well. i are my rows and j are my columns. What is the correct way to do it?
import java.util.Scanner;
public class Exercise08_01 {
public static void main(String[] args) {
[Code]....
Ok I am trying to at this point read in a matrix from a txt file in the format with order of the matrix leading the matrix. Like this :
1
5
2
2 3
5 9
3
3 -2 4
-1 5 2
-3 6 4
4
2 4 5 6
0 3 6 9
0 0 9 8
0 0 0 5
4
2 4 5 6
0 0 0 0
0 0 9 8
0 0 0 5
My code then is supposed to read it in and store it as an Array of singly linked lists. I am having trouble with my code, I am only getting outputs where it is only storing the first line of the txt matrixs like so:
5.0
2.0 3.0
2.0 3.0
3.0 -2.0 4.0
3.0 -2.0 4.0
3.0 -2.0 4.0
2.0 4.0 5.0 6.0
2.0 4.0 5.0 6.0
2.0 4.0 5.0 6.0
2.0 4.0 5.0 6.0
2.0 4.0 5.0 6.0
2.0 4.0 5.0 6.0
2.0 4.0 5.0 6.0
2.0 4.0 5.0 6.0
Is there something obvious in my code that is making it only save the first lines and how can i fix it.
//import java tools
import java.io.*;
import java.util.Scanner;
//Test.java
//See readMe.txt file for implementation instructions
//input: "input.txt"
[code]...
why my code is not printing the matrix and sum?
The Java-program Matrix below first asks the user for the number of rows and columns in a matrix. After this the program asks for the values of the elements. Finally, program prints the elements of the matrix and their sum on screen. Your task is to create the missing methods. Check the example print to see how to modify the print. When printing the matrix, values on the same row are separated using tabulator.
Program to complete:
import java.util.Scanner;
public class Matrix {
public static void main(String[] args) {
int rows, columns;
Scanner reader = new Scanner(System.in);
System.out.print("Type in the number of rows: ");
[code]...
Write the missing methods here / Methods are written in the text box below.
Example output
Type in the number of rows: 3
Type in the number of columns: 4
Type in the element 1 of the row 1: 1
Type in the element 2 of the row 1: 2
Type in the element 3 of the row 1: 3
Type in the element 4 of the row 1: 4
Type in the element 1 of the row 2: 5
[code]...
Matrix:
1 2 3 4
5 6 7 8
9 10 11 12
Sum of the elements of the matrix: 78
my code
import java.util.Scanner;
public class apples {
public static void main(String[] args) {
int rows, columns;
Scanner reader = new Scanner(System.in);
System.out.print("Type in the number of rows: ");
[code]...
I am making a Sudoku game and creating a matrix of JTextFields. However I am getting the following errors
Exception in thread "main" java.lang.NullPointerException
at SudokuView.board(SudokuView.java:30)
at SudokuView.<init>(SudokuView.java:18)
at SudokuMain.main(SudokuMain.java:5)
I know the problem is with this code
box[i][j] = new JTextField();
panel.add(box[i][j]);
I know this because when I do this:
panel.add(new JTextField());
It works. However it puzzles me why it is not working.
Whole Code:
import java.awt.GridLayout;
import javax.swing.*;
public class SudokuView {
JFrame frame;
JPanel panelBoard;
JTextField[][] box;
int row=10; int col=10;
SudokuView(){
frame = new JFrame("Play Sudoku GOOD LUCK");
[code]....
I am attempting to get the x and y coordinate of a matrix of buttons. I have googled my way to failure and read the docs and I think I am traveling of track.
Below is where I create a matrix of buttons via Swing
public class View extends Mybuttons{
private static final long serialVersionUID = 1L;
JFrame frame;
JPanel matrixPanel, optionsPanel;
Mybuttons[][] matrixBtn;
Later in this class:
JPanel matrixPan(){
matrixBtn = new Mybuttons[25][25];
JPanel panel = new JPanel();
panel.setSize(550,550);
panel.setLayout(new GridLayout(25,25));
//creating a 25x25 matrix of buttons
[Code]...
In the controller class I am trying to get the index of each button in the getUnvisitedChildNode method. I need to do this so I can search the buttons around the button passed to it and check if they are been visited yet. Below getUnvisitedChildNode you will be bfs (breadth first search).
private Mybuttons getUnvisitedChildNode(Mybuttons b){
//example of some of the things I have tried
int x= Mybuttons.getComponentAt(b);
int y= Mybuttons.indexOf(b);
int j=0;
return b;
}
[Code]...
I have a programming assignment in which I have to make a program which loads a crossword from a Properties file and then, when the user press a button, the program checks if the letters the user has typed in the interface are the same as in the correct matrix. If all the letters from a word are correct, the program must paint every letter of the word green.
I'm using two matrix, one that is called "mundo" (I 'm from Latin America) , which has the correct letter for each box. The other one is a JtextField matrix which ='ve created using a Gridllayout. I called this one crucigrama (crossword in Spanish)
This is the code I wrote to validate: So you can understand, here is a translation:
numero = number
fila = row
column = columna
bien - a boolean I used to check if the letter I've checked before are the same as the correct ones
.darLetra() - returns a string with the correct letter
[Code] .....
I have string abcdef.I need to convert that string into 2 dimensional matrix.For each 2 characters in the string will be a matrix.For instance:
String: abcdef
Matrix will be: [a b],[c d],[e f]
How to do that in java?
so I have this matrix
1 2 3 4
5 6 7 8
9 10 11 12
13 14 15 16
If the user for example enter the number 2 for index I need to swap the matrix from this index two lines with two line so this is the result what I need
1 2 5 6
3 4 7 8
9 10 13 14
11 12 15 16
I have to create a square matrix that has a min and max value as well as a size value which is given a integer value in the main method. The matrix has to be filled with random values. Also I have to add that matrix to another one in an addMatrix method and I have to subtract both in a subMatrix method. These are the requirements:
Methods:
Constructor() - receives the row and col size for myMatrix and a max and min values for range of random fill values for the matrix.
RandFill() - fills matrices with random numbers
addMatrix() - receives a matrix object. adds its myMatrix with the received object's myMatrix. The result is placed in this object's myResultMatrix.
subMatrix() - subtracts both matrices
I typed up this code but I'm not sure about some parts of it and I would creating min and max values in the Random method and in the main printing the separate 2 matrices and adding and subtracting them:
import java.util.*;
public class SquareMatrix2 {
public int size;
public int myMatrix [][];
public int myResultMatrix;
public int [][] ResultStatus;
[Code] ....