How To Compare Int To A Empty String To Input Error Message To User
Apr 16, 2015
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;
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
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!!");
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());
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()
I'm writing basically my first program for school. I've written small ones, following instructions, but this is the most vague. I'm having issues. I can't figure out what the error means. I'm not done with the code, but I think the ArrayList is throwing me off. I'm trying to gather user input and sum the total. Here's the code:
package graduationplanner; import java.util.ArrayList; import java.util.Scanner; import java.lang.Double; public class GraduationPlanner { public static void main(String[] args) {
I'm attempting to compare user input to a text file that I have set up whenever the user types in an employee ID number. I want to be able to tell the user that either the ID number is valid, or that it is not valid and must be re-entered by comparing it to the employee.txt file, and then record the valid ID number to the timeclock.txt file. I'm recording the next available employee ID number instead of the one I typed in. The output of the program looks like this: i82014/06/06 12:16:56 (I typed 1 as the employee ID.)
What I'm trying to do is compare String input to a char array. Let me make it a little more plain, I'm working on a cipher assignment, and my line of thought is this: I will get String input from the user, COMPARE the characters in the string input to an alphabet array, which will then be compared to the cipher array so that the cipher's counterpart can be chosen over the alphabet's. Any way that I might compare the random input keyed in by the user to that alphabet array?
Example : I have code and name but my code must start with the first letter of the inputed name if the 2 input is match it will be inserted into database
code = "A"001 name ="Angela" = success this will inserted into database
else
code ="B"002 name="Angela" =failed this will not inserted into database
else
code="A"003 name="Andy" =success still accepts the input cause they have diff code number
What I am thinking on this was compare the code the name? if == it will be inserted but how do i get the 1st letter of the input name?
I trying to get this code to get user input instead of reading from a hardcoded array. I'm getting compile errors while trying to get user input. Here's some of the code:
I have to take a users input. The general gist of the problem is I want to convert a decimal number entered by the user inputs into it's binary equivalent....the conversion part I know how to do.
I'm stuck at the user input phase. If the user inputs a decimal number within the correct range (lets say between 0-5000 for this example) the conversion goes ahead as planned and the program outputs on the screen the binary equivalent.
If on the other hand the user inputs a number outside of this range ... OR a String OR and empty space, an error message is given and the user is asked to try again. I don't know how to handle it if the user enters the different types...int or String.
I'm having an issue with my program that needs 2 lines of input when I only want one. First I call Scan.nextLine(); to fetch a word. Then I want Scan.findInLine(word).charAt(number); to scan the string word for a letter instead of having to put another line in the console. How do I make Scan.findInLine(word).charAt(number); scan a single String instead of scanning input typed by the user?
I am having trouble with getting a user input once they enter it in to a JTextArea and then storing it in to a string value. See, I wanted the user to enter an answer in to the JTextArea, and then once I store it in to a string value, I would be able to use it later. I wanted to after storing the variable to print it on to a JLabel, but nothing is showing up... Heres my code.
static String usera[]= new String [10]; for (int i=0; i< usera.length; i++) { //These are the JTextArea names usera[0]= Question1.getText(); usera[1]= Question2.getText();
[Code].....
I already initialized the JLabels earlier in my code, and I did not feel the need to post all my code here. This is where I am trying to get the string variable and then printing it out.
I am a first-timer using J2EE and here on coderanch.com and wanted to make a Simple Email-like System which a Registered User can Send Message/Email to another Registered User. how to do it. I have already my register/login process done but I'm stuck on how to make the Email. And I have an sample Bootstrap for my UserInterface which I want to use.
So this application gets input from the user and converts it into a string. It then uses various methods to set instance variables of this class and ends up printing those classes to display information to the user about that products.
package javaapplication5; import java.text.NumberFormat; import java.util.Scanner; public class Product { private String product; private String description; private double price;
[Code] ....
I am getting a logical error. My output is this:
Enter a product for information. Choose either Java or C++ java Prduct: null Description: null Price 0.0
I decided to code this quiz I took in class about asking the user to input a string and the code is suppose to check for upper case letters. If a upper case letter is found, it should increase a count by one. Once the check is done, it should display the number of uppercase letters. For some reason I am getting this weird compile error stating that symbols can't be found...
Java Code:
import java.util.*; import java.lang.*; public class StringCheck{ public static void main(String[] args){ Scanner input = new Scanner(System.in); System.out.println("please enter a string: " ); String s = input.nextLine();
I am trying to make a program that calculates the change due in dollars and cents. The user inputs both the amount due and the amount tendered. My program only works with whole numbers?
My assignment is to create a hangman game. One of my first difficulties with it is how to scan the string for an input supplied by the user.
Here is my method:
//Guesses that character c is in the secret word. //Updates all instance variables accordingly, //and returns true if c is present in the secret word. public boolean guessCharacter(char c){ }
I am creating a simple Symptom Checker application. The problem I have is that I'm trying to retrieve user input (JTextField) by comma's using StringTokenizer which contacts the database for a result which matches the user's input (SELECT * FROM DIAGNOSIS WHERE ?, ?, ?) . It successfully finds the correct result however only in a particular format. Not different combinations....
for example, if I enter say within the JTextField: "tearful, nausea, lack of motivation" it will find the result successfully (as that is how it is formatted within the particular column (in the database table) i wish to display a result from) however, if i enter a different combination of these symptoms: "nausea, lack of motivation, tearful" - it will not find any result. I'm very unsure how to make it work regardless of what is inputted first, second or last.
Here is the code:
public void actionPerformed(ActionEvent e) { try { String abc = fieldsymp1.getText(); StringTokenizer str = new StringTokenizer(abc); while (str.hasMoreTokens()) { str.nextToken((", ")).trim();
I need to design, implement, and test a program to input and analyze a name. The program begins by retrieving a user input string from the keyboard. This string is intended to be the user's name. These are the errors we have to search analyze the user input for: No blanks between names firstName and lastName, Non-alphabetic characters in names, Less than two characters in first name, and Less than two characters in last name. Each of these errors must be thrown. All exceptions must be derived from a programmer-defined class called NameException. Each exception should use a detailed message to differentiate among the file types of errors.
This is the format of my NameException class, is the format itself correct? I will fill in the details of each exception I am just wondering if that is how I should set it up.
public class NameException extends Exception { private String firstName, lastName; public NoBlanksException(String firstName,String lastName) { } public NonAlphabeticalCharactersException(String firstName, String lastName) {
[Code] .....
I was told not to try and catch thrown errors in the main method, would I just create another method in the Driver class to take care of that then?
I am writing a code in which a user inputs data as a string and that data must be verified as a valid number. A valid number is anything from 0-100. Then all valid numbers are converted into double numbers.
I am having trouble in how to write the validation part of the code.
Is it suppose to be an if, else statement? And if so how is it suppose to be validated?
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.
I have a method for a button so when a user inputs something it then will get the string value and check it against the string value within the properties file to see if it exists.
The properties file is called GitCommands.properties that contains -- > key = value <-- in it
I realised I have not used it correctly hence why I keep getting errors - I am lost on how to use it, I think perhaps that may be the issue here? I need to reference the file but I am doing it wrong? When I do use that piece of code I get null pointer exception too...
JButton btnSearch = new JButton("Search"); btnSearch.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { FindSelectedKey();
[code] .....
I understand I am missing my piece of code where it states "//determine whether the string is equal to the property file key string" I understand the logic fine but not actually coding it.
I'm having trouble to compare two string from my LinkedList. I took me 2 days now trying figure out how to compare the current string to previous string in the linkedlist. Here is my code.
public int compareTo(LinkedListNode n){ //Compare two string String myHead = data.toLowerCase(); String comparableHead = data.toLowerCase();
How do I compare a String to each element of a string array?
For example:
int headscount = 0; if (coins[i].equals("heads")){ headscount++; System.out.println("b" + headscount); }
This doesn't give me the right value because the IDE says that equals() is an incompatible type. I also tried changing the "heads" to an variable, but the results remains the same.
