Code Converts A String That Has All Numbers Into Integer
May 8, 2015
I am trying to code using error handling and I am a bit confused on how to go about doing it correctly. My code converts a string that has all numbers into an integer and the error handling should recognize that if it isn't a proper number and ask the user to try again or enter 'q' to quit.Do I place a throw new exception in the try block and put conditionals like if charAt(i) is some letter or a symbol then throw new exception?
Java Code:
import java.util.Scanner;
public class practice {
public static void main(String[] args) {
Integer finalValue = null;
boolean validValue = false;
Scanner scan = new Scanner(System.in);
int result = 0;
The code here I have works fine if I just want to ask the user to enter four digits: //java application that asks user to input binary numbers(1 or 0) and convert them to decimal numbers import java.util.Scanner; //program uses class scanner public class binarynumber{
//main method that executes the java application public static void main(String args[]){ //declares variables
int digit; int base=2; int degree; double decimal; int binary_zero=0; int binary_one=1; //create scanner for object input
[code]....
The thing is, I want the java application to input more than four digits for the user and I want it to loop it manytimes f until the user ask it to stop.
Write a program that will read two numbers and an integer code from the keyboard. The value of the integer code should 1, 2, 3, 4. If the value of the code is 1, compute the sum of the two numbers. If the code is 2, compute the difference (first number minus second). If the code is 3, compute the product of the two numbers. If the code is 4, and the second number is zero, compute the quotient (first divided by second). If the code is not equal to 1,2,3,4, display an error message. The program is then to display two numbers, the integer code and the computed result to the screen
here is the code that I have so far:
public static void main(String[] args) { Scanner read = new Scanner (System.in); int num1, num2, code, sum; System.out.println("Please enter a number"); num1 = read.nextInt();
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
My program gives me an error when I try to "digUp" the purse. The error appears in the purse class.
import java.io.*; public class Purse { //Fields public double gp; public double gold; public double silver; public double copper; public double platinum; public static final double GOLD_VALUE = 1;
a. Write a Java program to input 10 integer numbers into an array named fmax and determine the maximum value entered. Your program should contain only one loop, and the maximum should be determined as array element values are being input. (Hint: Set the maximum equal to the first array element, which should be input before the loop used to input the remaining array values.)
b. Repeat 1a, keeping track of both the maximum element in the array and the index number for the maximum. After displaying the numbers, display these two messages:
The maximum value is: _________ This is element number __________ in the list of numbers
Have your program display the correct values in place of the underlines in the messages.
c. Repeat 1b, but have your program locate the minimum value of the data entered.
I did parts a and b but for part see i just want to know if i did it correctly or not
import java.util.Scanner; public class MinimumValueArray { public static void main(String[] args) { //Variable Declaration Scanner keyboard = new Scanner(System.in); int size = 10;
[Code] ,.....
When I run it i get this The minimum value is 0.0
The element that holds the value is 0 right away. is this right for the minimum or am i supposed to enter values and it will display the minimum value like in parts a and b wit the maximum? will the minimum just always be 0 or ?
1. Create a program that will return the maximum and minimum numbers in the elements of ONE-dimensional integer array. Save it as MaxMin_OneDim.java
2. Create a program that will return the maximum and minimum numbers in the elements of each row in a TWO-dimensional integer array. Save it as MaxMin_TwoDim.java
3. Write a program PrintPattern which prompt a user to enter a number and prints the following patterns using nested loops (assumed user entered number is 8 output is:)
1 .... 87654321
12 .... 7654321
123 .... 654321
1234 .... 54321
12345 .... 4321
123456 .... 321
1234567 .... 21
12345678 .... 1
(Without the dots, i just put them to give spaces)
How do I code this without having the need to use iterator? Code a Java method that accepts an ArrayList of integers and an integer. The method should delete all elements in the array list exactly divisible by the integer and return the number of remaining elements.
I have to write a client and server class for a UDP protocol sending integer numbers by UDP packets. So far i have this;
Client Code:
import java.io.*; import java.net.*; class UDPClient { public static void main(String args[]) throws Exception { BufferedReader inFromUser = new BufferedReader(new InputStreamReader(System.in));
[Code] ....
But i now need to change this so that:
The client;
1. Reads an integer from keyboard input and stores its value in a UDP packet. // byte[] send = ByteBuffer.allocate(4).putInt(num).array(); ???
2. Sends the UDP packet to the server, on port number 1999;
3. Listens for UDP packets from the server (until it receives a packet with a non-positive number; see step (b) below). While listening:
(a) Once it receives a UDP packet from the server, it subtracts 2 from the integer value num contained in it. // int num = ByteBuffer.wrap(receive).getInt(); ??? (b) Checks the integer value num: if the value is greater than 0 (num>0) then the client stores it in a new UDP packet and sends the packet to the server; otherwise (num<=0) the client terminates.
The Server;
1. Listens on port 1999;
2. For each UDP packet it receives from a client: (a) extracts the integer value n contained in it; (b) decreases the value of n by 2; (c) sends back to the client a UDP packet containing the new value of n.
Code: public static void main(String[] args) { // TODO code application logic here Calendar time = Calendar.getInstance(); int min = 1;//time.get(Calendar.MINUTE); String blank = "0"; int checker = ((min > 10 ) ? min : blank+min); System.out.println("The time is " + "12" + ":" + checker ); }
This is my code, as you can see, I have if the min is less than 10, display the string "0" next to it so it will be something like
blank is zero and min is one
So it will display as 01 but after min reaches 10 and above, the 0 goes away. Problem I have is, you just cant add "blank" to int checker because checker is an int and blank is a string. So what must I do in order for it to display the 0 under checker?
I've started writing a new program that Scans for some strings. I want to specify a random Integer to those Strings in order to do my desired idea. what should I do?!! my codes are here :
import java.util.Random; import java.util.Scanner; public class Draw { public static void main(String[] args) { System.out.println("This Program is written to solve little problems in families cause of doing unwanted works!!");
[code].....
now I want to Specify an Integer to each person that has been scanned! for example if the first person is " David " , which is a String, in the next step :
Random randomNumber = new Random(); randomNumber.NextInt(101); int David = randomNumber.NextInt(101);
I have to make a programm where the user gives you the bank sorting code and the account number and you give him the IBAN. That was so far no problem and I was done within minutes except of one thing that I simply can't figure out even though im trying since weeks. At some point I have to convert a string to integer. My research told me its with parseInt() and I dont get a syntax error when I compile my programm (using BlueJ). But when executing the programm stops and gives me some weird bug message. Here is code and bug message:
Java Code:
public class IBAN { public IBAN(String Bankleitzahl, String Kontonummer) { Bankleitzahl=Bankleitzahl.replace(" ",""); // Die Leerzeichen werden entfernt int Anzahl=Bankleitzahl.length(); // Auf der Variabel Anzahl wird die Anzahl der Zeichen von der Bankleitzahl gespeichert
but when I put this second line, the conversion, the program stops to work. I tried also with Integer.valueOf(timeInterval) but again I had the same problem.
If I use the class DecimalFormat to format long number, how can I convert it back to integer?
DecimalFormat longFormat = new DecimalFormat("#,###"); long testLong=11000; String strLong=longFormat.format(testLong); System.out.println("NUM : " + strLong); //Assume that at this point I don't have //testLong, I have only the strLong value... long newLong=Long.parseLong(strLong) * 2; //java.lang.NumberFormatException: For input string: "11,000
I am making a simple dice game and am using JOptionPane for my input, however, all input has to be a String. I need to be able to input an integer. 'note, I am using java JDK'.
public static void main(String[] args) { Scanner scanner = new Scanner(System.in); System.out.println(" Enter the maximum number "); int maxNumber = scanner.nextInt(); int[]numberList = createList (maxNumber);
[code]....
I have a problem with the output. It only get as far as marking the multiples of 2. It does not mark the multiples of 3 and so on.Example output: If the range is from 2 to 15 the output is :2, 3, 0, 5, 0, 7, 0, 9, 0, 11, 0, 13, 0, 15 note: 0 means its marked.As you can see it only marks multiples of 2 but it does not mark multiples of 3 above. I think the problem lies in the for loop inside my main method, because the index does not increment.
I am doing a project to generate three names of fruits. When I take out my switch code the numbers generate randomly, but when I added the switch code back I kept getting three instances of "Bars" as if the random numbers all became 5.
public static void main(String[] args) { System.out.println("Enter the amount of money you would like to gamble."); Scanner keyboard = new Scanner(System.in); int num1; int num2; int num3; int money; money = keyboard.nextInt();
I'm having an issues with adding integer values to a string list. The question is asking me "the method should iterate over runners, and for each runner generate a random number between 90 and 180 (inclusive) which should be used to set the time (in minutes) for that runner."
I have been able to get the random number and iterating over the runner arraylist but I haven't been able to figure out how to add the values generated into the runners list. I am also using BlueJ.
Here's the whole code I have at the moment:
import java.util.*; import java.io.*; import ou.*; import java.util.Random; /** * Write a description of class MarathonAdmin here. */ public class MarathonAdmin { // instance variables - replace the example below with your own
i am interested to add integer objects and String objects into any collection object ..... while iterating the collection object i am not interested to do any type cast in java
When learning HashMaps in C++ I had to create the whole algorithm. In the code I created I could simply place a string into the method and it would store the names for me by turning the string into a integer and storing is accordingly. If there was a collision it would grow linearly at that location.
//play with Hash Tables void getNames(String names) { HashMap<String, Integer> map = new HashMap<String, Integer>(); map.put(names,22); }
How can I do this in Java. I read about them and look at examples and they all for the most part look like this.
