Simple Program to sort Arraylist in Ascending and Descending order. U can also sort String,Float,Double.. etc in ArrayList.
ArrayList can be sorted using inbuilt java 1.5 class method Collections.sort(..).
Here is code, save it as file : Sorting.java
import java.util.*;
public class Sorting
{
public static void main(String[] args)
{
//Initilize ArrayList
ArrayList<Integer> arrayList = new ArrayList<Integer>();//also it can sort String,Float,Double.. etc
//creating Random numbers
//Random is a inbuilt java class in 1.5 in util package
Random random = new Random();
//putting Values
for(int i=1;i<=10;i++)
{
int temp = random.nextInt(100);//get random int values between 0 and 100
arrayList.add(temp);
}
//Sorting ArrayList
System.out.println("Before Sorting..");
System.out.println(arrayList);
Collections.sort(arrayList);//Sorting using sort method, default ascending sort
System.out.println("After Sorting Ascending..");
System.out.println(arrayList);
//useing Comparator to sort in descending order
Comparator<Integer> comparator = Collections.reverseOrder();
Collections.sort(arrayList,comparator);//Descending sorting using sort method
System.out.println("After Sorting Descending..");
System.out.println(arrayList);
}
}