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passing an array as an argument; Setting up Array in Java with user input with Scanner Class

I am trying to take user input, place it into my array, display the array and then print all the values larger than the "n" values the user provides. I think I am close, but I can't get the user input to go to the array. I keep getting an error in eclipse when I call the method (main at very bottom) the "arrayValues" cannot be resolved to a variable:
import java.util.Arrays;
import java.util.Scanner;
public class LargerThanN {
//initialize n
static int n;
static int arraySize;
//setup the array
static int [] integerArray = new int [] {};
public static void printGreaterThanN(int[] integerArray, int n) {
for (int i = 0; i < integerArray.length; i++) {
if (integerArray[i]>n) {
System.out.println(integerArray[i]);
}
}
}
public static int[] fillArrayWithUserInt() {
Scanner sc = new Scanner(System.in);
System.out.println("How big will the array be?");
int arraySize = sc.nextInt();
sc.nextLine(); // clears rest of input, including carriage return
int[] integerArray = new int[arraySize];
System.out.println("Enter the " + arraySize + " numbers now.");
for (int i = 0; i < integerArray.length; i++) {
integerArray[i] = sc.nextInt();
}
return integerArray;
}
/**
* This method prints the array to the standard output
* #param array
*/
private static void displayArray( int[] integerArray) {
for (int i = `0; i < integerArray.length; i++) {
System.out.print(integerArray[i] + " ");
}
}
public static void main(String[] args) {
int [] array ;
array = fillArrayWithUserInt();
Scanner sc = new Scanner(System.in);
fillArrayWithUserInt();
displayArray(array);
System.out.println("To which number would you like to compare the rest? Your n value is: ");
n = sc.nextInt();
printGreaterThanN(array, n);
but now my output looks like:
How big will the array be?
4
Enter the 4 numbers now.
1 2 3 4
How big will the array be?
3
Enter the 3 numbers now.
1 2 3
1 2 3 4
To which number would you like to compare the rest? Your n value is:
2
3
4

Heads up, the following code does nothing in java...
public void set(int n, int value) {
n = value;
}
You seem to written code like this in many functions where a value should be returned.
For example, the function definition :
static void fillArrayWithUserInt(int[] integerArray, int arraySize, int arrayValues, int n)
Should really be written as :
static int[] fillArrayWithUserInt()
It could be implemented as follows
public static int[] fillArrayWithUserInt() {
Scanner sc = new Scanner(System.in);
System.out.println("How big will the array be?");
int arraySize = sc.nextInt();
sc.nextLine(); // clears rest of input, including carriage return
int[] integerArray = new int[arraySize];
System.out.println("Enter the " + arraySize + " numbers now.");
System.out.println("What are the numbers in your array?");
for (int i = 0; i < integerArray.length; i++) {
integerArray[i] = sc.nextInt();
}
return integerArray;
}
The above function will ask the user for the array size. Create the array with the given size. Then prompt the user to fill the array with the correct number of values. The array created in this process is then returned.
All you must handle differently now is finding the value to compare. This must be done outside the fillArrayWithUserInt function.
Like so :
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
int[] array = fillArrayWithUserInt();
displayArray(array);
System.out.println("To which number would you like to compare the rest? Your n value is: ");
int n = sc.nextInt();
printGreaterThanN(array, n);
}
Lastly, you should not need to declare any static variables at the top of your class.
These lines can all be deleted :
//initialize n
static int n;
static int arraySize;
//setup the array
static int [] integerArray = new int [] {};

Here is my solution check it out.
import java.util.Scanner;
public class LargerThanN {
static int[] integerArray = null;
static int n ;
public static void printGreaterThanN() {
for (int i = 0; i < integerArray.length; i++) {
if (integerArray[i] > n) {
System.out.println(integerArray[i]);
}
}
}
public static void fillArrayWithUserInt() {
Scanner sc = new Scanner(System.in);
System.out.println("How big will the array be?");
int arraySize = sc.nextInt();
sc.nextLine(); // clears rest of input, including carriage return
integerArray = new int[arraySize];
System.out.println("Enter the " + arraySize + " numbers now.");
System.out.println("What are the numbers in your array?");
for (int i = 0; i < integerArray.length; i++) {
integerArray[i] = sc.nextInt();
}
System.out.println("To which number would you like to compare the rest? Your n value is: ");
n = sc.nextInt();
}
/**
* This method prints the array to the standard output
*
* #param array
*/
private static void displayArray() {
for (int i = 0; i < integerArray.length; i++) {
System.out.print(integerArray[i] + " ");
}
}
public static void main(String[] args) {
fillArrayWithUserInt();
displayArray();
printGreaterThanN();
}
}

i wrote a code using array and methods to display numbers from the smallest o the largest numbers

i wrote a code using array and method that allow the user to enter any number of numbers and
display the numbers sorted from the smallest number to the largest number however the program works but it doesn't show the numbers here is the code that i wrote
import java.util.Scanner;
public class Numbers {
public static void main(String[] args) {
Scanner s = new Scanner(System.in);
System.out.println("How many numbers you want to enter? ");
int size = s.nextInt();
int i;
double[] numbers1 = new double[size];
System.out.println("Enter " + numbers1.length + " numbers: ");
getNumbers(numbers1);
double[] numbers2 = new double[numbers1.length];
for (i = 0; i < numbers1.length; i++) {
numbers2[i] = numbers1[i];
}
displayNumbers(numbers1);
System.out.println("The numbers after sorting are: ");
sortNumbers(numbers2);
displayNumbers(numbers2);
}
public static void getNumbers(double[] numbers) {
Scanner s = new Scanner(System.in);
for (int i = 0; i < numbers.length; i++) {
numbers[i] = s.nextDouble();
}
}
public static void sortNumbers(double[] numbers) {
double temp;
double pass;
for (pass = 0; pass < numbers.length; pass++) {
for (int i = 0; i < numbers.length - 1; i++) {
if (numbers[i] > numbers[i + 1]) {
temp = numbers[i];
numbers[i] = numbers[i + 1];
numbers[i + 1] = temp;
}
}
}
}
public static void displayNumbers(double[] numbers) {
Scanner s = new Scanner(System.in);
for (int i = 0; i < numbers.length; i++) {
numbers[i] = s.nextDouble();
System.out.print(numbers + " ");
}
System.out.println();
}
}

Your displayNumbers() method is wrong. In the loop you wrote:
numbers[i] = s.nextDouble();
System.out.print(numbers + " " );
You're trying to read again 4 doubles (everytime you call that method) and you're printing the whole array (which doesn't do what you'd expect). What you probably want is this:
System.out.print(numbers[i] + " " );

Your code is inefficient and unclear.
You don't need to create a new Scanner everytime and also why instead of println the array with Arrays.toString(double[]).
You should also make more cleaner instructions and variable names.
Here is an example of how the code should be
public static void main(String[] args)
{
//create a new Scanner with a name that defines it
Scanner scanner = new Scanner(System.in);
//print your instructions
System.out.println("How many numbers would you like to sort?");
//print "> " to let the user to know he should be entering values
System.out.print("> ");
//read the number the user has entered which we will define as how many numbers he would enter next
int totalNumbers = scanner.nextInt();
//create a new array the size of the total numbers
double[] unsortedNumbers = new double[totalNumbers];
//tell the user to enter his unsorted numbers
System.out.println("Enter your unsorted numbers: ");
//loop totalNumbers times until the whole unsortedNumbers is full
for(int index = 0; index < totalNumbers; index++)
{
System.out.print("> ");
unsortedNumbers[index] = scanner.nextDouble();
}
//Print the numbers he entered
System.out.println("You entered: ");
//Arrays.toString prints the array in format [number, number, ...]
System.out.println(Arrays.toString(unsortedNumbers));
//sort the arrays with Arrays.sort which sorts in ascending numerical order
Arrays.sort(unsortedNumbers);
//Print the final result - sorted numbers
System.out.println("Sorted: " + Arrays.toString(unsortedNumbers));
}

return array from one method to another method

This is my program and every time it is asking me to input the array.
I want to input a array once and process on that array.
But this program is asking me to input array again.
from method named "first" I just want to return array and use that array in two different methods add and delete. But it is always asking me to input all the elements of array that is every time the first method is running while i call any add or delete method from main method.
package Program;
import java.util.Arrays;
import java.util.Scanner;
public class Functionality {
public static int[] first( )
{
System.out.println("Enter the number of element in array");
Scanner num = new Scanner(System.in);
int data = num.nextInt();
//return data;
Scanner ar = new Scanner(System.in);
int arr[] = new int[data];
System.out.println("Enter "+data+" Numbers");
for(int i =0; i<data; i++){
System.out.println("Enter NUmber :"+(i+1));
arr[i] = num.nextInt();
}
System.out.println();
System.out.println(Arrays.toString(arr));
return arr;
}
public static void main(String[] args) {
add();
delete();
}
static void add(){
int arr[]=first();
System.out.println("Enter the number you want to add");
Scanner one = new Scanner(System.in);
int naya = one.nextInt();
for(int i = 0; i<=arr.length-1; i++){
arr[i]= arr[i] + naya;
}
System.out.println("The added array is");
System.out.println(Arrays.toString(arr));
}
static void delete(){
int arr[]=first();
System.out.println("Enter the number you want to substract");
Scanner two = new Scanner(System.in);
int arko = two.nextInt();
for(int i =0; i <= arr.length-1; i++ ){
arr[i]=arr[i]-arko;
}
System.out.println("The Substracted array is");
System.out.println(Arrays.toString(arr));
}

You should obtain reference to an array and passing it during subsequent methods invocations.
This should do the trick:
class Functionality {
static int[] first() {
System.out.println("Enter the number of element in array");
Scanner num = new Scanner(System.in);
int data = num.nextInt();
//return data;
Scanner ar = new Scanner(System.in);
int arr[] = new int[data];
System.out.println("Enter " + data + " Numbers");
for (int i = 0; i < data; i++) {
System.out.println("Enter NUmber :" + (i + 1));
arr[i] = num.nextInt();
}
System.out.println();
System.out.println(Arrays.toString(arr));
return arr;
}
public static void main(String[] args) {
int arr[] = first();
add(arr);
delete(arr);
}
static void add(int arr[]) {
System.out.println("Enter the number you want to add");
Scanner one = new Scanner(System.in);
int naya = one.nextInt();
for (int i = 0; i <= arr.length - 1; i++) {
arr[i] = arr[i] + naya;
}
System.out.println("The added array is");
System.out.println(Arrays.toString(arr));
}
static void delete(int arr[]) {
System.out.println("Enter the number you want to substract");
Scanner two = new Scanner(System.in);
int arko = two.nextInt();
for (int i = 0; i <= arr.length - 1; i++) {
arr[i] = arr[i] - arko;
}
System.out.println("The Substracted array is");
System.out.println(Arrays.toString(arr));
}
}
Your program is asking You every time to input array, because every time You invoke method first() new array is being created

How can I print out the int values from the array?

The code below shows my progress, but I cannot print the numbers that were entered. I don't know where to put println("you entered the following numbers") in the loop so that it'll show up when the loop stops.
import java.util.Scanner;
public class aufgabe5 {
public static void main(String[] args) {
int x;
Scanner input = new Scanner(System.in);
System.out.println("How much numbers do you want to enter?");
x = input.nextInt();
int j = 1;
Scanner scanner = new Scanner(System.in);
int[] numbers = new int[x];
for (int i = 0; i < numbers.length; i++) {
System.out.println("Enter the " + j++ + ". number:");
numbers[i] = scanner.nextInt();
}
System.out.println("You entered following numbers");
System.out.println(x);
}
}

Change x like
System.out.println(x);
to Arrays.toString(int[]) like
System.out.println(Arrays.toString(numbers));
Edit
To print the array reversed,
String str = Arrays.toString(numbers).replace(", ", " ,");
str = str.substring(1, str.length() - 1);
System.out.println(new StringBuilder(str).reverse().insert(0, "[")
.append("]"));

Intialize the String before the loop, then keep adding the values to it.
After the loop finishes you can print the whole thing.
String someVar="You entered following numbers: ";
for(int 1=0;i<array.length;i++)
{
someVar=someVar+numbers[i]+",";
}
System.out.println(someVar);

how to take user input in Array using java?

how to take user input in Array using Java?
i.e we are not initializing it by ourself in our program but the user is going to give its value..
please guide!!

Here's a simple code that reads strings from stdin, adds them into List<String>, and then uses toArray to convert it to String[] (if you really need to work with arrays).
import java.util.*;
public class UserInput {
public static void main(String[] args) {
List<String> list = new ArrayList<String>();
Scanner stdin = new Scanner(System.in);
do {
System.out.println("Current list is " + list);
System.out.println("Add more? (y/n)");
if (stdin.next().startsWith("y")) {
System.out.println("Enter : ");
list.add(stdin.next());
} else {
break;
}
} while (true);
stdin.close();
System.out.println("List is " + list);
String[] arr = list.toArray(new String[0]);
System.out.println("Array is " + Arrays.toString(arr));
}
}
See also:
Why is it preferred to use Lists instead of Arrays in Java?
Fill a array with List data

package userinput;
import java.util.Scanner;
public class USERINPUT {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
//allow user input;
System.out.println("How many numbers do you want to enter?");
int num = input.nextInt();
int array[] = new int[num];
System.out.println("Enter the " + num + " numbers now.");
for (int i = 0 ; i < array.length; i++ ) {
array[i] = input.nextInt();
}
//you notice that now the elements have been stored in the array .. array[]
System.out.println("These are the numbers you have entered.");
printArray(array);
input.close();
}
//this method prints the elements in an array......
//if this case is true, then that's enough to prove to you that the user input has //been stored in an array!!!!!!!
public static void printArray(int arr[]){
int n = arr.length;
for (int i = 0; i < n; i++) {
System.out.print(arr[i] + " ");
}
}
}

import java.util.Scanner;
class bigest {
public static void main (String[] args) {
Scanner input = new Scanner(System.in);
System.out.println ("how many number you want to put in the pot?");
int num = input.nextInt();
int numbers[] = new int[num];
for (int i = 0; i < num; i++) {
System.out.println ("number" + i + ":");
numbers[i] = input.nextInt();
}
for (int temp : numbers){
System.out.print (temp + "\t");
}
input.close();
}
}

You can do the following:
import java.util.Scanner;
public class Test {
public static void main(String[] args) {
int arr[];
Scanner scan = new Scanner(System.in);
// If you want to take 5 numbers for user and store it in an int array
for(int i=0; i<5; i++) {
System.out.print("Enter number " + (i+1) + ": ");
arr[i] = scan.nextInt(); // Taking user input
}
// For printing those numbers
for(int i=0; i<5; i++)
System.out.println("Number " + (i+1) + ": " + arr[i]);
}
}

It vastly depends on how you intend to take this input, i.e. how your program is intending to interact with the user.
The simplest example is if you're bundling an executable - in this case the user can just provide the array elements on the command-line and the corresponding array will be accessible from your application's main method.
Alternatively, if you're writing some kind of webapp, you'd want to accept values in the doGet/doPost method of your application, either by manually parsing query parameters, or by serving the user with an HTML form that submits to your parsing page.
If it's a Swing application you would probably want to pop up a text box for the user to enter input. And in other contexts you may read the values from a database/file, where they have previously been deposited by the user.
Basically, reading input as arrays is quite easy, once you have worked out a way to get input. You need to think about the context in which your application will run, and how your users would likely expect to interact with this type of application, then decide on an I/O architecture that makes sense.

**How to accept array by user Input
Answer:-
import java.io.*;
import java.lang.*;
class Reverse1 {
public static void main(String args[]) throws IOException {
int a[]=new int[25];
int num=0,i=0;
BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
System.out.println("Enter the Number of element");
num=Integer.parseInt(br.readLine());
System.out.println("Enter the array");
for(i=1;i<=num;i++) {
a[i]=Integer.parseInt(br.readLine());
}
for(i=num;i>=1;i--) {
System.out.println(a[i]);
}
}
}

import java.util.Scanner;
class Example{
//Checks to see if a string is consider an integer.
public static boolean isInteger(String s){
if(s.isEmpty())return false;
for (int i = 0; i <s.length();++i){
char c = s.charAt(i);
if(!Character.isDigit(c) && c !='-')
return false;
}
return true;
}
//Get integer. Prints out a prompt and checks if the input is an integer, if not it will keep asking.
public static int getInteger(String prompt){
Scanner input = new Scanner(System.in);
String in = "";
System.out.println(prompt);
in = input.nextLine();
while(!isInteger(in)){
System.out.println(prompt);
in = input.nextLine();
}
input.close();
return Integer.parseInt(in);
}
public static void main(String[] args){
int [] a = new int[6];
for (int i = 0; i < a.length;++i){
int tmp = getInteger("Enter integer for array_"+i+": ");//Force to read an int using the methods above.
a[i] = tmp;
}
}
}

int length;
Scanner input = new Scanner(System.in);
System.out.println("How many numbers you wanna enter?");
length = input.nextInt();
System.out.println("Enter " + length + " numbers, one by one...");
int[] arr = new int[length];
for (int i = 0; i < arr.length; i++) {
System.out.println("Enter the number " + (i + 1) + ": ");
//Below is the way to collect the element from the user
arr[i] = input.nextInt();
// auto generate the elements
//arr[i] = (int)(Math.random()*100);
}
input.close();
System.out.println(Arrays.toString(arr));

This is my solution if you want to input array in java and no. of input is unknown to you and you don't want to use List<> you can do this.
but be sure user input all those no. in one line seperated by space
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
int[] arr = Arrays.stream(br.readLine().trim().split(" ")).mapToInt(Integer::parseInt).toArray();