I'm having an issue, I have a scanner (Scan.nextLine();) that scans the console for input to fetch the string "word". Then I want to fetch a character using Scan.findInLine(word).charAt(number);. The problem is that the console requires me to write 2 lines in order for the program to move on. I only want the program to scan for a word, and then move on with what it has instead of requiring 2 inputs.
View RepliesI am having a great deal of frustration trying to use the scanner to get user input from the eclipse console. Here is what I am trying to do.
Print a menu for the user with options, take that (1) char input and run it into a switch statement for processing. I have that done and it is working fine.
If the user chooses to enter strings for storage, They are instructed to enter their string and press enter to complete that string entry. Then enter the next string and press enter, etc.
So I have a While loop for this. Get the scanner input, store it in the LinkedList, get the next scanner input, etc. I get the scanner string and store it in a Linked list. That works fine. The user is instructed to simply enter a blank string to end the entry procedure, like just press Enter on the new line without typing a new string.
The problem is the scanner doesn't seem to return anything for me to Test to close this procedure. How do I TRAP the fact that the user just pressed enter so I can end my procedure? I have tried next() and nextLine() and reset(), etc. And I am getting knowhere.
I am trying to make a program in which first I am entering number of charachters and then in nextline their is exactly that number of characters should be enter after than program should stop taking input from console..this is I have try so far
private static ArrayList<String> chars;
static String inputdata;
public static void main(String[] args) {
Scanner in=new Scanner(System.in);
chars=new ArrayList<String>();
[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 am attempting to write a application that asks user input of a decimal, and outputs a value rounded to the nearest integer of the input.
Here is what I have so far, and I am seeing an error at Static Scanner Console that says Cannot Find Symbol for the class Scanner. and I am not sure how to resolve it.
Note the program so far is only asking for input - I have not gotten to the output part yet.
public class IT145Exercise13 {
static Scanner console = new Scanner(System.in);
/**
* @param args the command line arguments
*/
public static void main(String[] args) {
double decimal;
int rounded;
[Code] ......
This is my second Java program (First was HelloWorld, which went really well )
Seems I need to include
import java.util;
when I do, the error at the console line goes away.
I am not clear what this import statement is doing so will check that out.
I have built a binary tree, from a file. In each node, I am storing each word as a string, and an int frequency for each time the word occurs. For the assignment, I need to find how many words occur only once in the file. I wrote the program, but for some reason I am getting a number different from what my professor is expecting.
As far as I know, this file has loaded into the tree correctly, because all of my other answers in the assignment are correct. What am I doing wrong?
public void findUnique() {
System.out.println("There are " + findUniqueWords(root, 0) + " unique words.");
}
private int findUniqueWords(Node subTree, int uniqueCount) {
// Base Case: At the end of the branch
if(subTree == null){
return uniqueCount;
[Code] ....
I have a small bug in my program. The user is asked what person(s) information they want to access but lets say they want captain they must enter "captain" twice. I think it will make more sense to you with the code. I have searched all over to see what is causing the bug but still have found no resolution. I even tried making two different scanners but that didn't work either.
I know the while loop (line 16) I am using is causing the bug because it works fine without that but then I cannot validate the input.
package myproject;
import java.util.Scanner;
public class Enterprise {
public static void main (String[]args){
String userInput;
[Code]......
I'm having some kind of weird problem reading input from a file. It says that my scanner object I'm using to hold an item of information isn't initialized, when I do try to initialize it, it says error variable already initialized. I'm using the scanner to read input from a file whose contents are this
10
150.4
88.4
-3.14
499.4
799.4
1299.8
0
1900.2
901.7
4444.4
This is my program
import java.util.*;
import java.io.*;
public class QudratullahMommandi_3_07 {
Toolkit_General toolKit = new Toolkit_General();
public static void main (String[]args)throws IOException
[Code] .....
This is the error message
QudratullahMommandi_3_07.java:34: error: variable holder2 might not have been initialized
String holder2 = holder2.trim();
^
1 error
----jGRASP wedge2: exit code for process is 1.
----jGRASP: operation complete.
Is there any way to use scanner to get input and distinguish between int and text? I'm trying to make a scanner method I can call whenever I need user input no matter if I need int or text. Using two methods (one for int, other for text) at the moment.
import java.util.Scanner;
public class Application {
public static void main(String[] args) {
Person person1 = new Person();
System.out.println("What is your name?");
[Code] .....
So I clipped this out of my Jeopardy game code and made it into its own project for testing. using this code I want to check to see if the input for wage is an integer?
import java.util.Scanner;
public class test {
/**
* @param args
*/
public static void main(String[] args)
{
Scanner input = new Scanner (System.in);
Obviously right now if you enter "aflwkj" or some such for the wager, the program terminates. How to make a loop that will keep asking the user for a value for wage until the input is an integer?
I'm trying to read user input from the terminal and separate the input into separate arrays depending on if the user input is an integer, scanner, or a string. The terminal should keep asking the user for input until the user types "quit".
import java.util.*;
public class arrayScanner {
public static void main(String[] args) {
ArrayList<Integer> intList = new ArrayList<Integer>();
ArrayList<Double> doubleList = new ArrayList<Double>();
ArrayList<String> otherList = new ArrayList<String>();
[code].....
Assignment: Your task is to implement a similar scheme to store polynomials of any number of terms, such that the number of terms and the components (coefficient, variable and exponent) of every term are entered from the keyboard. To implement the interactive input we will using the Java class Scanner, defined in the java.utils standard package. The Scanner class can be used in Java to read data types from a file.
Since the input console (keyboard) is treated as the file called System.in, we can create a Scanner for that input stream as new Scanner (System.in), as shown below. Once you define a Scanner object, using its method next() you can read Strings from the file/keyboard. The incomplete program below is your assignment. You are supposed to complete without changing the existing code. Your output should be the terms of the polynomial entered by the user, separated by + signs. Additional instructions in the code below, that you will change to achieve the requested functionality.
import java.util.Scanner;
public class Polynomials {
public static void storeTerm (int coeff, String var, int exp, String poly[][], int
where){
//ENTER THE COEFFICIENT, VARIABLE AND EXPONENT INTO THE
//ARRAY POLY THAT REPRESENTS THE POLYNOMIAL, AT POSITION "where"
//THAT RANGES BETWEEN INDEX 0 AND POLY.LENGTH-1
[Code] ....
Anyways, I'm not looking for straight answers. I just want to know which section I should start on first because I was advised to tackle programs one problem at a time.
I Just made a simple code, but in any case it's not taking the input I'm trying to enter for the city.
View Replies View RelatedThe method below is called within a large loop in another method. The code has been boiled down to easily show the problem I'm having. I found that the method worked fine (prompts user for input, gets input, returns input) until I added a statement at the end of the method that closes the Scanner object. When the kb.close() statement is present, the method works the first time through, but subsequent calls to this method only display the prompt and the Scanner object never waits for the user to input anything thereafter.
public int scanIt()
{
int i;
Scanner kb = new Scanner(System.out);
System.out.print("==> "); // prompt for input
if(kb.hasNextInt())
{
i = kb.nextInt();
System.out.println("User entered " + i);
}
kb.close();
}
I want to input character data from the console without using the BufferedReader class. I tried using the Scanner class but the compiler shows an error. This is what I tried:
sc.nextCharacter();
sc.nextcharacter();
sc.nextChar();
Sc.nextchar();
Is there any way I can input character data without using the BufferedReader class?
I have this very simple application just to test console input:
import java.util.ArrayList;
import java.util.Scanner;
public class WriteTester {
[Code]....
When I let it run, only every third entry is put into the array list and I have to hit "enter" three times for the "break" in line 21 to trigger. I cannot find out why.
this is my code...in my code i cant give input form my console...it takes input but it doesn't save in a target file..My code is :-
package filetester;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Scanner;
[code]....
I couldn't get this code working:
import java.util.*;
public class scan {
public static void main (String args[]) {
String testi;
Scanner scan = new Scanner(System.in);
[Code] .....
Did i write something wrong or can't Scanner be used with String?
I am currently tackling homework for a small I/O-program with console input.Right now, only the part when you enter "E" or "e" on the console is implemented and the issue I am trying to tackle is described in the comment starting at line 38:
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Vector;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.lang.reflect.InvocationTargetException;
import java.util.Scanner;
[code]....
//Scanner Test
String stream2 = "ab34ef
56";
// create a new scanner with the specified String Object
Scanner scanner = new Scanner(stream1);
// find a string "World"
[Code] ....
Matched expression found by findInLine: 34
ef56
is new line? right?
The java.util.Scanner.nextLine() method advances this scanner past the current line and returns the input that was skipped. This method returns the rest of the current line, excluding any line separator at the end.
then 56 is in new line and it must return ef.What is the problem?
How does the Scanner goes through the String which is passed to it as a parameter. For example, String input = "222 dddd 222 ddd22" is passed to the method and here's the code:
Java Code:
public static void sum(String anything)
{
Scanner input = new Scanner(anything)
while(input.hasNext())
{
if(input.hasNextDouble())
{
double nextNumber = inut.nextDouble();
sum += nextNumber
}
......
......
} mh_sh_highlight_all('java');
{
So, how does Scanner calculates a passed String? I just want to know the way it calculates/reads.
This may be a multipart question. Basically I have to write a program that accepts a string, converts it to a double splits it and then performs a calculation.
public static void main(String[] args) {
String input = ""; // initalize the string
boolean isOn = true; // used for the while loop...when false, the program will exit.
String exitCommand = "Exit"; // exit command
String[] token = input.split(("(?<=[-+*/])|(?=[-+*/])"));
[Code] ....
This is the error I get:
Enter a math problemException in thread "main" java.lang.NumberFormatException: empty String
at sun.misc.FloatingDecimal.readJavaFormatString(Floa tingDecimal.java:1842)
at sun.misc.FloatingDecimal.parseDouble(FloatingDecim al.java:110)
at java.lang.Double.parseDouble(Double.java:538)
at Calculator.main(Calculator.java:22)
[Code] .....
How do I go about actually fixing it. Without that line commented out I get this:
Enter a math problem
2+2 <-What I entered
[Ljava.lang.String;@135fbaa4
Also, how would I go about using the submethods to check for valid operands and operators (also part of the problem) I have the actual lists made obviously, but am unsure how to get those to work with the problem.
We were suppose to make a program for an assignment and the prof provided some codes to start of. What does this basically mean? How do i access the string arrays from consolelist?
class ConsoleInfo {
private String conTitle;
private double conPrice;
private int conQty;
private String conPic;
private static String empPassword;
ConsoleInfo(String title, double price, int qty,String pic)
[Code]...
I am trying to create a program that first asks the user for an input in the form: condition = value, where condition is a word from the set {limit, deficient, abundant, perfect, prime}, and value is a positive integer. Then it verifies the input. If the input is invalid it prints a message indicating that and terminates. If the input is valid it prints a table with the number of abundant, deficient, perfect and prime numbers less than or equal to N, where N = 1, 2, 3, ..., limit.
My problem is with the input validation. i want it to read the value as a string and verify if it's integer.
Here is my code
import java.util.Scanner;
public class Factors
{
public static void main (String[] args)
{
Scanner scan = new Scanner(System.in);
int n, f, fsum, p=0, a=0, d=0,pe=0,limit=0,abundant=0, deficient=0;
System.out.print("Enter stoping condition (condition = value): ");
String cond = scan.next();
[Code] ....
Write an application that asks the user to enter his/her first name, last name, birthday, and where you born (all fields type String) and prints their information to the console. Use the techniques discuss in class. The data must be encapsulated. The program must be coded in Notpad++ and compiled in the Command Prompt.
Output should be like this:
Welcome!
What is your first name? Carlos
What is your last name? De La Torre
When is your birthday? 08/12/1979
Where did you born? Puerto Rico
First Name: Carlos
Last Name: De La Torre
Birthday : 08/12/1979
Born in : Puerto Rico
This is what I have so far :
package myinfo;
import java.util.Scanner;
public class MyInfo {
private String name;
private String lastName;
private String birthday;
private String birthPlace;
[Code] ....
package jdbc;
import java.sql.*;
import javax.sql.*;
import java.util.*;
public class Jdbc {
public static void main(String[] args) {
[code]....