Solved

ArrayList trick

Posted on 2009-07-13
5
342 Views
Last Modified: 2013-12-29
I have two Strings .

d1="40-60-70"; // the data are id values basically

d2="60-70-80"; // the data are id values basically

I want to make an ArrayList with id's which are not present in d2 but in d1.

So, my expected output is ArrayList {"40"}


whats the easiest way to do this ?
0
Comment
Question by:cofactor
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
5 Comments
 
LVL 23

Assisted Solution

by:Ajay-Singh
Ajay-Singh earned 50 total points
ID: 24839573
You can use the following,
1. Split the string by "-", So you will get an array
2. Sort the array
3. Iterate over array to find out the missing element(s)
0
 
LVL 20

Accepted Solution

by:
a_b earned 60 total points
ID: 24839585
1. Tokenize str1 and store in arrayList1
2. Tokenize str2 and store in arrayList2
3. for each token in arrayList1 check arrayList2.contains(token)
4. for each token in arrayList2 check arrayList1.contains(token)
5. Do processing accordingly
0
 
LVL 1

Expert Comment

by:nitin22
ID: 24839598
Check if this helps!

import java.util.Set;
import java.util.TreeSet;
 
public class Main {
  public static <T> Set<T> union(Set<T> setA, Set<T> setB) {
    Set<T> tmp = new TreeSet<T>(setA);
    tmp.addAll(setB);
    return tmp;
  }
 
  public static <T> Set<T> intersection(Set<T> setA, Set<T> setB) {
    Set<T> tmp = new TreeSet<T>();
    for (T x : setA)
      if (setB.contains(x))
        tmp.add(x);
    return tmp;
  }
 
  public static <T> Set<T> difference(Set<T> setA, Set<T> setB) {
    Set<T> tmp = new TreeSet<T>(setA);
    tmp.removeAll(setB);
    return tmp;
  }
 
  public static <T> Set<T> symDifference(Set<T> setA, Set<T> setB) {
    Set<T> tmpA;
    Set<T> tmpB;
 
    tmpA = union(setA, setB);
    tmpB = intersection(setA, setB);
    return difference(tmpA, tmpB);
  }
 
  public static <T> boolean isSubset(Set<T> setA, Set<T> setB) {
    return setB.containsAll(setA);
  }
 
  public static <T> boolean isSuperset(Set<T> setA, Set<T> setB) {
    return setA.containsAll(setB);
  }
 
  public static void main(String args[]) {
    TreeSet<Character> set1 = new TreeSet<Character>();
    TreeSet<Character> set2 = new TreeSet<Character>();
 
    set1.add('A');
    set1.add('B');
    set1.add('C');
    set1.add('D');
 
    set2.add('C');
    set2.add('D');
    set2.add('E');
    set2.add('F');
 
    System.out.println("set1: " + set1);
    System.out.println("set2: " + set2);
 
    System.out.println("Union: " + union(set1, set2));
    System.out.println("Intersection: " + intersection(set1, set2));
    System.out.println("Difference (set1 - set2): " + difference(set1, set2));
    System.out.println("Symmetric Difference: " + symDifference(set1, set2));
 
    TreeSet<Character> set3 = new TreeSet<Character>(set1);
 
    set3.remove('D');
    System.out.println("set3: " + set3);
 
    System.out.println("Is set1 a subset of set2? " + isSubset(set1, set3));
    System.out.println("Is set1 a superset of set2? " + isSuperset(set1, set3));
    System.out.println("Is set3 a subset of set1? " + isSubset(set3, set1));
    System.out.println("Is set3 a superset of set1? " + isSuperset(set3, set1));
 
  }
}

Open in new window

0
 
LVL 1

Expert Comment

by:nitin22
ID: 24839607
Your program will populate the sets by tokenizing the strings that you have.
0
 
LVL 8

Assisted Solution

by:ozlevanon
ozlevanon earned 40 total points
ID: 24840548
Here is a code to do that.
Note that the first list is created with new since Arrays.asList returns an immutable list, and we want to remove items from it.
			String d1="40-60-70"; // the data are id values basically
			String d2="60-70-80"; // the data are id values basically
			List<String> list1 = new ArrayList<String>(Arrays.asList(d1.split("-")));
			List<String> list2 = Arrays.asList(d2.split("-"));
			list1.removeAll(list2);

Open in new window

0

Featured Post

[Webinar] How Hackers Steal Your Credentials

Do You Know How Hackers Steal Your Credentials? Join us and Skyport Systems to learn how hackers steal your credentials and why Active Directory must be secure to stop them. Thursday, July 13, 2017 10:00 A.M. PDT

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

INTRODUCTION Working with files is a moderately common task in Java.  For most projects hard coding the file names, using parameters in configuration files, or using command-line arguments is sufficient.   However, when your application has vi…
After being asked a question last year, I went into one of my moods where I did some research and code just for the fun and learning of it all.  Subsequently, from this journey, I put together this article on "Range Searching Using Visual Basic.NET …
Viewers learn about the third conditional statement “else if” and use it in an example program. Then additional information about conditional statements is provided, covering the topic thoroughly. Viewers learn about the third conditional statement …
Viewers learn about the “for” loop and how it works in Java. By comparing it to the while loop learned before, viewers can make the transition easily. You will learn about the formatting of the for loop as we write a program that prints even numbers…

695 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question