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
View RepliesI'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
[Code] .....
I have a data structure such as: ArrayList<ArrayList<Integer,String>
The data looks as [[1,2,3] [3,4] [99,98,40,32,45,65,1]]
I am trying to access each element and put them into a hashtable such as:
Hashtable<Integer,String>
With what I am doing below I am getting an out of bound error but can't see any other way of accessing the element
public static void hash(ArrayList<ArrayList<String>> list)
{
for(int i = 0; i < list.size(); i++)
{
int cnt = 0;
for(int y = 0; y < list.size(); y++)
{
if (! hashMap.containsValue(list.get(i).get(y)))
{
hashMap.put(cnt, list.get(i).get(y));
cnt++;
}
...
What is wrong in this
class Gen<k,v>
{
K a;
V b;
Gen(K s, V f) {
a=s;
b=f;
[Code] .....
a is object of type k,then how can I retrieve content of a?
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.
View Replies View RelatedI am solving a problem in which first my program will ask a number N and then N numbers form the user
suppose:
5
4 3 4 5 6
another
6
3 2 7 8 9 3
and I am using this code
inputValues=new LinkedHashMap<Integer, Integer>();
Scanner in=new Scanner(System.in);
int N=in.nextInt();
String inputString=in.nextLine();
[Code] .....
But its not working as i want . Where is fault?
Set<? super TreeMap> s = new HashSet<SortedMap>();
SortedMap<String,String> sm = new TreeMap<String,String>();
TreeMap<String,String> tm = new TreeMap<String,String>();
s.add(sm); //This fails
s.add(tm);
Why does adding sorted map to a Set that allows ? super TreeMap and instantiated as such fail?
My book defines this generic method
Java Code:
public static <E extends Comparable<E>> void sort(E[] list... mh_sh_highlight_all('java');
Comparable is an interface and from how i look at this piece of code is that I can only use a class that implements the Comparable interface; however, this is the context my book uses when explaining the following code
First, it specifies that E is a subtype of Comparable.
Second, it specifies that the elements to be compared are of the E type as well.
What does it mean when it says E is a subtype.
I am very new to coding and I am struggling with one of my intro to Java Projects. This project involves creating a GUI that has a list of trees and their possible heights, giving each tree a range for their possible minimum and maximum heights.
I am having trouble creating this method for the TreeDatabase (TreeDB class):
public String queryByPossibleHeight(int key) Instructions for this method are as follows: this method creates and returns a single string that contains the trees that can be found such that the value key is in the range for possible height. Traverse the entire ArrayList of Trees and for each one of the trees contained in the ArrayList invoke the method inRange() from the class Tree. Pass to the method inRange() the parameter key. If inRange() returns true, invoke the method toString() from the class Tree. Append the value returned by invoking the method toString() to the String result, adding a “” at the end. Once the entire ArrayList has been traversed, return the String result.
My 3 classes so far (I haven't gotten to the actual GUI yet):
public class Range {
private int low;
private int high;
private int value;
public Range(int plow,int phigh){
low = plow;
high = phigh;
[Code]...
As you can see in the last TreeDB class, in the public String queryByPossibleHeight(int key) method I have something wrote in, but I was just testing random things.
I'm working with Doubly Linked Lists and using Java Generics..
My nodes looks like this:
class DNode<E> {
DNode<E> previous;
DNode<E> next;
E element;
//and all methods inside
}
My list of Nodes looks like this:
class DLL<E>{
private DNode<E> head;
private DNode<E> tail;
private int size;
[code]....
As you can see, as arguments they get "E o"...I need to write a program, which from the main function asks the users how long is the list, and after they type it's length, I ask them to start typing the elements (integers)...and this is how my main method is written, but I can't seem to make it work, specialy when I call the "insLast" method,I guess it's because the arguments i'm giving to the function...how to read the elements and write them into the list?
public static void main(String[] args) throws IOException {
DLL<Integer> lista=new DLL<Integer>();
BufferedReader stdin = new BufferedReader(new InputStreamReader(System.in));
String s = stdin.readLine();
int N = Integer.parseInt(s);
s = stdin.readLine();
String[] pomniza = s.split(" ");
for (int i = 0; i < N; i++) {
lista.instLast(Integer.parseInt(pomniza[i]));
}
}
I have doubt in generics,
List<int> c=new ArrayList<int>();
why we cannot use primitive data type like int,double.
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 want to what should I do?
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
[Code] .....
I want to conver String value into Integer, and I have this :
String timeInterval = tfInputTinter.getText();
Integer tint=(Integer.parseInt(timeInterval))*1000;
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.
I am having problem in converting JSTL variable into integer type in JSP (not using Spring). I am looking to do something like below:
<c:set var="total_amt">${list.totalAmount}</c:set>
<c:when test="${new Integer(total_amt) > 500}">
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'.
View Replies View Relatedi want to take integer from a file into a string and using stringtokenizer convert them into tokens and collect those tokens into an array and sort it
View Replies View RelatedI 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;
[code]....
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.
I am looking for a good and reliable library to read a string to construct a list of Integers, Doubles, Booleans, etc. This library should be robust enough to handle faulty input from an inexperienced user.
Example:
input: "1, 2, 3, 4"
output List<Integer> [1, 2, 3, 4]
input: "1, 2, 3.6, 4"
output List<Double> [1.0, 2.0, 3.6, 4.0]
input: "true, true, false"
output List<Boolean> [true, true, false]
input: "[1, 2, 3]"
output List<Integer> [1, 2, 3]
input: "(1, 2, 3)"
output List<Integer> [1, 2, 3]
It would be really nice if such a library would already exist.
I'm trying to do something like this:
Java Code:
for (int i=1; i<2; i++);
int randomNum = rn.nextInt(range) + 1;
if (randomNum == CardList.CARD_NAME[randomNum]){
} mh_sh_highlight_all('java');
But the CARD_NAME variable is a string. I just want to compare the array to the integer.
Run the code along with the attached csv file. The GUI contains a short explanation of what I am looking for. I have tried converting the integer array to a string array but the output is not the same as the command line. I receive errors when I compile.
View Replies View RelatedI need to allow users only enter integer into a String variable, "input" and I am not sure what statement to use.
import java.util.Scanner;
public class assq2b {
public static void main(String []args) {
Scanner reader = new Scanner(System.in);
String input,b;
[Code] ......
I'm actually trying to complete the excersise of the Servlets and JSP book in page 303 but I'm getting the following error in Eclipse Cannot cast from String to ArrayList(JSP).Here is the code
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<%@ page import="java.util.*" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Hobbies Sharing</title>
</head>
[code]...
The error as it appears in line <% ArrayList al = (ArrayList)request.getParameter("Names"); %>