Java Collection How to - Search List

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Question

We would like to know how to search List.

Answer

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
//w ww .  j  a  v  a  2  s.c om
public class Main {
  public static void main(String args[]) {
    String simpsons[] = { "Bart", "Hugo", "Lisa", "Marge", "Homer",
        "Maggie", "Roy" };

    // Convert to list
    ArrayList list = new ArrayList(Arrays.asList(simpsons));

    // 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, "Maggie");
    System.out.println("Found Maggie @ " + index);

    // Search for element not in list
    index = Collections.binarySearch(list, "Jimbo Jones");
    System.out.println("Didn't find Jimbo Jones @ " + index);

    // Insert
    int newIndex = -index - 1;
    list.add(newIndex, "Jimbo Jones");
    System.out.println("With Jimbo Jones added: [length: " + list.size()
        + "]");
    System.out.println(list);
  }
}

The code above generates the following result.

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