How do I sort string of numbers in ascending order?

In the following example we are going to sort a string containing the following numbers "2, 5, 9, 1, 10, 7, 4, 8" in ascending order, so we will get the result of "1, 2, 4, 5, 7, 8, 9, 10".

package org.kodejava.util;

import java.util.Arrays;

public class SortStringNumber {
    public static void main(String[] args) {
        // We have some string numbers separated by comma. First we
        // need to split it, so we can get each individual number.
        String data = "2, 5, 9, 1, 10, 7, 4, 8";
        String[] numbers = data.split(",");

        // Convert the string numbers into Integer and placed it into
        // an array of Integer.
        Integer[] intValues = new Integer[numbers.length];
        for (int i = 0; i < numbers.length; i++) {
            intValues[i] = Integer.parseInt(numbers[i].trim());
        }

        // Sort the number in ascending order using the
        // Arrays.sort() method.
        Arrays.sort(intValues);

        // Convert back the sorted number into string using the
        // StringBuilder object. Prints the sorted string numbers.
        StringBuilder builder = new StringBuilder();
        for (int i = 0; i < intValues.length; i++) {
            Integer intValue = intValues[i];
            builder.append(intValue);
            if (i < intValues.length - 1) {
                builder.append(", ");
            }
        }
        System.out.println("Before = " + data);
        System.out.println("After  = " + builder);
    }
}

When we run the program we will get the following output:

Before = 2, 5, 9, 1, 10, 7, 4, 8
After  = 1, 2, 4, 5, 7, 8, 9, 10

How do I turn on the Scroll Lock button?

The program below show you how to turn on the Scroll Lock button programmatically. Setting the locking state to Boolean.TRUE activate the Scroll Lock.

package org.kodejava.awt;

import java.awt.*;
import java.awt.event.KeyEvent;

public class TurnScrollLockOn {
    public static void main(String[] args) {
        // Gets the default toolkit.
        Toolkit toolkit = Toolkit.getDefaultToolkit();

        // Update the locking state for scroll lock button to true
        // will turn the scroll lock on.
        toolkit.setLockingKeyState(KeyEvent.VK_SCROLL_LOCK, Boolean.TRUE);
    }
}

How do I turn on the Num Lock button?

The example below show you how to activate the Num Lock button programmatically. Setting the locking state to Boolean.TRUE will turn the Num Lock on.

package org.kodejava.awt;

import java.awt.Toolkit;
import java.awt.event.KeyEvent;

public class TurnNumLockOn {
    public static void main(String[] args) {
        // Gets the default toolkit.
        Toolkit toolkit = Toolkit.getDefaultToolkit();

        // Update the locking state for num lock button to true
        // will turn the num lock on.
        toolkit.setLockingKeyState(KeyEvent.VK_NUM_LOCK, Boolean.TRUE);
    }
}

How do I turn on the Caps Lock button?

The code below show you how to activate the Caps Lock button programmatically. Setting the locking state to Boolean.TRUE will turn the Caps Lock on.

package org.kodejava.awt;

import java.awt.Toolkit;
import java.awt.event.KeyEvent;

public class TurnCapsLockOn {
    public static void main(String[] args) throws Exception {
        // Gets the default toolkit.
        Toolkit toolkit = Toolkit.getDefaultToolkit();

        // Update the locking state for caps lock button to true 
        // will turn the caps lock on.
        toolkit.setLockingKeyState(KeyEvent.VK_CAPS_LOCK, Boolean.TRUE);
    }
}

How do I read the status of Scroll Lock key?

This example show you how to detect if the Scroll Lock key is in active mode. If you run the program you will get an output telling you that the Scroll Lock button is active or not active.

package org.kodejava.awt;

import java.awt.Toolkit;
import java.awt.event.KeyEvent;

public class ScrollLockState {
    public static void main(String[] args) {
        Toolkit toolkit = Toolkit.getDefaultToolkit();

        // Get the locking state of the Scroll Lock button. This method 
        // return boolean true value if it is "on".
        boolean isOn = toolkit.getLockingKeyState(KeyEvent.VK_SCROLL_LOCK);

        System.out.println("ScrollLock button is " + (isOn ? "on" : "off"));
    }
}