java - Sorting ArrayList of Objects by Object attribute

Question

I am having an Arraylist of Objects. Those object have an attribute or datatype - 'String'. I need to sort the Arraylist by that string. How to achieve this?

Answer 1

You need to write a Comparator<MyObject> and use Collections.sort(List<T>, Comparator<? super T> to sort your List.

Or else, your MyObject can also implements Comparable<MyObject>, defining a natural ordering that compares on your specific attribute, and then use Collections.sort(List<T> instead.

See also

• Java Tutorials/Object Ordering

Related questions

On sorting List on various criteria:

• Sorting an ArrayList of Contacts

On Comparator and Comparable

• When to use Comparable vs Comparator
• difference between compare() and compareTo()
• Comparable and Comparator contract with regards to null
• Why does the Java Collections Framework offer two different ways to sort?