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 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'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 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());
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'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 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.
I've been beavering away with Java for a few months. But as with all languages the String implementation looks designed to trip up even experienced programmers.
My current development gets data from various sources outside my control. When I get a string I want to test if it is empty/null/or whatever. Simple enough one thinks.
But if you search the internet you see everone seems to have a slightly different approach. So what is the best way of determining that a string is not useful to you?
I've had success with this
if(string == null || string.length() == 0)
But I've seen people using methods - not necessarily of String (e.g equals, empty) and regular expressions.
What is the best approach to this considering coding efficiency and/or processing efficiency (accepting you'd have to be processing a lot of strings for the latter to be an issue).
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.)
I have an empty string and I want to add to it crosses and naughts. I want to simulate a board of TicTacToe game. My goal is print out 5 strings like this : "xox xxx oxo". There are 3 groups of symbols separated with a space. The crosses and naughts are filled randomly.
Random rand = new Random(); char[] characters = new char[] { 'x', 'o' }; int numOfTimes = 0; while (numOfTimes < 5) { String board = ""; String space = " "; for (int group = 0; group < 3 ; group++)
I want to make a program in which i write the Months Strings via while into the checkbox.
I already did that but i have also to add an day if February is a loop day.
So my question is how to say java that if Months is equal to February & year is a leap year, add 1. (i didn't wrote the year code because it's not relevant for my problem.)
Java Code:
public String[] Months ={"January","February","March","April","May", "June", "July", "August", "September", "Oktober", "November", "December"}; public Asg1KeapYear() { initComponents(); int MonthNo = 0;
[Code] ....
Netbeans shows me .equals() on incompatible types on Months.equals, do i have to declare it somehow?
I'm trying to implement a Binary Search Tree that accepts strings. I cannot figure out how to compare the string value in my add method against the node object. While I could make the node class data be the string type I am trying to make the code be as reusable as possible. So my question is this, is there a simple way I can compare the two that I am missing?
public class BTNode<E> { private E data; private BTNode<E> left, right; //constructor public BTNode(E initialData, BTNode<E> initialLeft, BTNode<E> initialRight) { data = initialData; left = initialLeft; right = initialRight;
I'm attempting a small program as I'm teaching myself the ropes. In it, I need to compare one string (the base) to another which is just the base string that's had it's characters shuffled.
Java Code:
String base = "ABCDEFG" String shuffled = "CDAFBEG" mh_sh_highlight_all('java');
What I need to do is run a loop that shuffles the base string each time, but compares and saves any characters that match in the correct location. For example, if shuffled = "CDAFBEG", then the G would be "locked" in place and the rest of the characters shuffled and looped back to the comparison.
I have all the code I need for shuffling the string, but I'm not sure how I would go about comparing each character and then also locking it in place. I get the basics, I think, of needed to use several variables.
I think my code is correct, but I cannot input any value into the parameter without it returning an error. I have tried different forms of the time (0734, 7:34, 7,34, and others) but none of them work. I attached a screenshot of the error message. How can I input the parameter?
public class Time extends Object { private int itsHour; // always in the range 0 to 23 private int itsMin; // always in the range 0 to 59 /** Create an object for the given hour and minute. If min * is negative, adjust the values to make 0 <= min < 60. */
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:
This is a program to input a sentence and print the words that start with a vowel.......There is no syntax error but on executing and typing the sentence and pressing enter,I get a error saying :
java.lang.StringIndexOutOfBoundsException: String index out of range: 0 at java.lang.String.charAt(String.java:658) at sentence.main(sentence.java:22)
