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Binary Searching

import java.util.ArrayList; import java.util.Arrays; import java.util.Collections; import java.util.List; public class MainClass {   public static void main(String args[]) {     String str[] = { "B", "H", "L", "M", "I", "N", "R" };     // Convert to list     List list = new ArrayList(Arrays.asList(str));     // Ensure list sorted     Collections.sort(list);     System.out.println("Sorted list: [length: " + list.size() + "]");     System.out.println(list);     // Search for element in list     int index = Collections.binarySearch(list, "M");     System.out.println("Found M @ " + index);     // Search for element not in list     index = Collections.binarySearch(list, "J");     System.out.println("Didn't find J @ " + index);     // Insert     int newIndex = -index - 1;     list.add(newIndex, "J");     System.out.println("With J added: [length: " + list.size() + "]");     System.out.println(list);   } } Sorted list: [length: 7] [B, H, I, L, M, N, R] Found M @ 4 Didn't find J @ -4 With J added: [length: 8] [B, H, I, J, L, M, N, R]