How To Accept Enter As Empty Input
Nov 8, 2014How can I get enter(return) as empty input from user?!
scanner.next will wait until I input a string ...
But I want it when I hit return sets the variable to empty string ...
How can I get enter(return) as empty input from user?!
scanner.next will wait until I input a string ...
But I want it when I hit return sets the variable to empty string ...
I am learning Java on my own, and I am creating little programs to do so.The program below asks the user to input text and hit enter. When user does that, it asks if that is correct. If the user enters "y," the program ends. That's good.If the users enters "n," the strGrategul is set to empty which triggers the while statement to start over again. That's good. However, when the program asks the user to "Tell me one thing you are grateful for..." it doesn't wait for user input. Instead it skips to "You said ''? Enter 'y' or 'n'" It thinks the user enter an empty line.
public static void main(String[] args) {
String strGrateful = "";
String strGoal = "";
String strContinue = "";
Scanner scn = new Scanner(System.in);
[code]....
This is what i've done so far.
table.addKeyListener(new KeyListener() {
public void keyPressed(KeyEvent e) {
if (e.getKeyCode()==KeyEvent.VK_ENTER) {
model.addRow(new Object[]{"", "","",""}); } }
public void keyReleased(KeyEvent e) { }
public void keyTyped(KeyEvent e) { } } );
I've added JTable to JPanel and used DefaultTableModel. I have to add a new empty Row to table after i press enter key. But somehow I've not been successful so far.
I have a GUI with a JTextField. I need to check that the input entered by the user is made up of only integers.
For example I accept: 1, 10, 530, ...
I do not accept: -10, 1.5, -6 ...
I would like to implement this control by using a regular expression so I would have a code like that.
JTextField text = new JTextField();
String input = text.getText();
boolean bool = checkInteger(input);
if(bool)
System.out.println("Ok");
else
System.out.println("Error");
The checkInteger(String input) method should check if the input string is correct or not.
How can I do to implement this control with regular expressions?
Is there an easier way to do it?
I am trying to create a fortune teller and everything is running fine except the program does not prompt you to answer the questions
Do you like donuts?
and
What did you have for breakfast?
Here is the code this is in Bluej :
import java.util.Scanner;
public class FortuneTeller {
public static void main(String[] args) {
Scanner keyboard = new Scanner(System.in);
System.out.println("Welcome to Fortune Teller");
[Code] .....
This program is supposed to accept an integer as an input and display the message that the number is even or odd. The main method calls a Boolean method. Write a method private static boolean iseven(int number and the message is printed from the Main method. This is what I have.
import java.util.Scanner;
public class OddorEven {
int number;
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
[Code] ....
I know the message is not being printed from the Main method. I'm not sure how to do that.
I want to write a program that accepts user input and then prints its average in a serial way.
Suppose i enter 5. I should get result 5 first time then i input 10 then it should return the average of (5 and 10) and then i enter say 20 it should return average of (5,10 and 20) and so on.
I am attempting to write a program that accepts input of a positive integer, reports each digit and then the sum of all digits. This is what I have so far:
*/
package numbersum;
import java.util.*;
public class Week4NumberSum {
static Scanner console = new Scanner(System.in);
/**
* @param args the command line arguments
[Code]...
It works if I enter 1234567891 (10 digits)
Enter a positive integer: 1234567891
digit: 1
digit: 2
digit: 3
digit: 4
digit: 5
digit: 6
digit: 7
digit: 8
digit: 9
digit: 1
The sum of the digits is 46
But if I enter 11 digits, it fails:
Enter a positive integer: 123456789123 (12)
Exception in thread "main" java.util.InputMismatchException: For input string: "123456789123"
at java.util.Scanner.nextInt(Scanner.java:2123)
at java.util.Scanner.nextInt(Scanner.java:2076)
at week4numbersum.Week4NumberSum.main(Week4NumberSum. java:26)
java - Scanner error with nextInt() - Stack Overflow gives me some infor for InputMismatchException - which I find described as In order to deal with this exception you must verify that the input data of your application meet its specification. When this error is thrown, the format of the input data is incorrect and thus, you must fix it, in order for your application to proceed its execution.
I don't understand why the 10 digit integer is OK but the 11 or > digit integer is a mismatch.
I am having issues with the program below everything works but I can't figure out a way to add code that if a user just hits enter without inputting anything it says "entering in nothing is not a valid choice" I am stuck on how to compare a int to a string ...
//import statements
import java.util.*; //for scanner class
// class beginning
public class Guess {
public static void main(String[] args ) {
//Declare variables area
[Code] ....
I've been trying to get my program to not accept empty strings when the user inputs, but I'm having some difficulties. I've tried for loops, as well as while loops.
import java.util.Scanner;
public class GasMileage
{
/**
* displayIntro
* This method displays the introduction to the user
*/
public static void displayIntro()
[Code] .....
I have the code below that just keeps getting the user's name and displaying it until the user enter's an empty string. Well, to simulate that, I just hit the keyboard instead of entering any name but for some reasons I am not seeing in my code, the programme just keeps looping.
System.out.println("Enter your name :
");
Scanner st = new Scanner(System.in);
while(st.hasNext()){
System.out.println("Enter your name :
");
String name = st.nextLine();
System.out.println(name);
if(name==" ") break;
}
System.out.println("you are out of the while loop now!!");
I made a guess a number program but I am having issue figuring out a way that when a user enter's in nothing for the program to spit out a message saying "hey entering nothing doesn't work try again" then ask for input. I have done some research and from what I have found is to read the input in as a String rather than int, and use something like Integer.valueOf() to get the integer value but I am completely lost on how to apply that to my program here is my code
//import statements
import java.util.*; //for scanner class
// class beginning
public class Guess {
public static void main(String[] args ) {
//Declare variables area
int guess, secretNumber = (int) (Math.random() * 10 + 1), lowGuess,highGuess;
[Code] ....
The project is a program that allows the user to enter students and enter grades for each student. One of the requirements is that if there is already a grade stored for the student that it will display the previous grade. IF the user then enters a new grade the new grade will be stored. IF the user simply presses enter (enters an empty string) nothing is done. I have everything working except for the requirement of doing nothing if the user enters an empty string. If I just press enter at this point I get a NumberFormatException.
The below code is a method "setTestGrades" from the student class. This method iterates through each student object stored in an array list and then checks if there is a previous grade (Requirement# unset grades have to default to -1) before allowing the user to set a new grade.
public void setTestGrades(int testNumber) { //Sets the grade for the specified test number for each student in the arraylist.
testNumber -= 1;
Scanner input = new Scanner(System.in);
for (int i = 0; i < studentList.size(); i++) {
System.out.println("Please enter the grade for Test #" + (testNumber + 1) + " For Student " + studentList.get(i).getStudentName());
[code]....
I want to limit the program to only accept a 12 digit input and an integer value but I don't know how to program it,
import java.util.Scanner;
public class testing4
{
public static void main(String []args) {
Scanner reader = new Scanner(System.in);
String input;
[Code]...
I am writing a short quiz program, and when the user inputs their answer they hit the enter key (the are int). But the last question on my quiz is asking the user to they want to repeat the quiz, but when I run the program, it won't allow me to input any information. I can briefly remember my lecturer saying something about entering in a code after each int the user inputs but I can't remember what it was.
Here is a snippet of my code:
//Question 3
do{
System.out.println("Question 3- What Hollywood actor did Mila Kunis have a baby with recently?");
System.out.println( question3 + ".Ashton Kutcher 2.Bradly Cooper 3.Leonardo Dicaperio h.Get a hint");
answer3 = stdIn.nextInt();
if(answer3 != question3)
[Code] ....
Ok so I have my program working for the most part. In this program I am supposed to take input from the user until they enter a negative number and that works, the problem is that it doesn't work if I enter a negative number on the first prompt. For example if I enter a 100 it would prompt me again and if I enter a negative number it would quit and give me the average, but if I enter a negative number the first time I am prompted the program just gives me an error. How do I fix that?
import java.util.List;
import java.util.ArrayList;
import java.util.Scanner;
public class Application {
public static void main(String [] args){
Scanner input = new Scanner(System.in);
List<Integer> grades;
[Code] ....
How to improve my code. I finally was able to create a program that gives you the corresponding letter grade, when you enter in a numeric grade without using an array. The only issue left is that I have to be able to enter 5 grades at a time, and it give me the letter grade for all 5. I have the programming working, but only am able to enter 1 at a time. I am not sure what kind of loop or if I am supposed to use a loop.
public static void main(String[] args){
{
int grade = 0;
Scanner input = new Scanner(System.in);
System.out.println("Enter : ");
grade = input.nextInt();
if (grade >= 90)
[Code] .....
A friend and I are working on a project in which we must test "super anagrams" (anagrams in which all characters in the first string are found in the second). We have a driver and definitions class pasted below:
Definition
class SuperAnagram{
String left = new String("");
String right = new String("");
[code]....
In the driver class, we get "cannot find symbol" errors at the beginning of cleanStrings and isSuper, both inside and outside of the if statement.
Basically, I'm just trying to let the user enter the name. It crashes whenever the input isn't an int. Also, here's the bit of code I'm using that has to do with that. I don't feel like putting the entire class, so here's that bit of code:
PHP Code: String yourName = user.nextLine(); mh_sh_highlight_all('php');
Anyway, I just haven't figured out how. Also, the scanner is called user in this class.
i was reading my book when in a code,it used accept(),but it did'nt talk about it.would you explain to me where to use accept().(the chapter was about socket programming)
View Replies View RelatedA program to create a class that contains a method that accepts compass directions and displays the same. You need to ensure that the method must accept any one of the directions: NORTH, SOUTH, EAST, WEST, NORTHEAST, SOUTHEAST, SOUTHWEST or NORTHWEST.
View Replies View RelatedI have a method that accepts as a parameter an object:
public void addClient(Client c){ }
Client is a class which has a constructor that has two String parameters:
public Cliente (String name, String lastname){
this.name = name;
this.lastname = lastname;
}
In the main add a Client in this way:
addClient(new Cliente("first", "second"));
Now, i have an array of Client, so I would like to enter within this. Example:
public void addClient(Client c){
for (int i = 0; i<client.length ; i++) { // client is an array of Client object
client[i] = c; // Enter a c in the array, but does not work!
System.out.println("test "+clienti[i]); // print Client@15db9743
}
}
I have used the println for check if worked insertion, but the result shows no
I wrote a couple classes and am trying a test driver but it is having an error I do not know how to solve.
Student Class:
public class Student{
private Course[] courseList;
private static int numCourses;
private final int maxCourses;
public Student(int max){
maxCourses = max;
[Code] .....
Error:
javac tester.java
tester.java:6: error: cannot find symbol
one = new Course(name);
^
symbol: variable name
location: class tester
1 error
Same issue, just only one error as there is only one line. It seems like it does not accept my parameters as it cannot find symbol.
I forgot to put the "" in the brackets, it's been a month since I have looked at any java and made this simple mistake.
The program is to accept a string and display all the palindrome words(the words that are same even if they are reversed-------->mom,madam,malayalam etc.)in the string.
I need to solve this program urgently.
There are no syntax errors but after typing in the sentence,no output is displayed. This is my program....
import java.util.*;
class palindrome_test
{
public static void main(String args[])
{
Scanner in=new Scanner(System.in);
System.out.println("Enter a sentence");
String usersInput=in.nextLine();
[Code] .....
I have a HashMap with multiple values at runtime. In that map one key has empty value , how to avoid this value to add in a list. some code sample is below:
public HashMap getLoop2Map(Map map, String xslFile , int sheetNo){
HashMap hashMap = new HashMap();
try{
ArrayList list = new ArrayList();
System.out.println("-------Map : " +map);
list.add(map.values());
//System.out.println("------- boolean : " +val);
System.out.println("------List : " +list);
}
I do not want to add the empty value in a list ...
result in map
-------Map : {Free Text Entry={},
Mouth / Throat={Free Text Entry={Free Text Entry=<FORMFILENAME>EditChartPhysicalExamText.form
</FORMFILENAME><TAG>"<MUSCULOSKELETAL.PE>"</TAG>},
Salivary Glands Condition={Salivary Glands Condition=MouthAttribute},
Examination Overview- Mouth / Throat={Examination Overview- Mouth / Throat=MouthAttribute},
Tonsils={Tonsils=MouthAttribute},
[Code] ....
I want to downoald a file stored in system directory but when downloading the file in jsf page I get it empty. this is my xhtml page :
<h:form>
<h:commandButton value="Download" action="#{helloBean.downloadFile}" />
</h:form>
and my managed bean :
@ManagedBean
@SessionScoped
public class HelloBean {
public void downloadFile() {
File file = new File("C:datacontacts.doc");
HttpServletResponse response = (HttpServletResponse)
[Code] ....