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copied!<p>There are plenty of questions to look at that answer this, such as: <a href="https://stackoverflow.com/questions/2784514/sort-arraylist-of-custom-objects-by-property%20sort%20arraylist%20of%20objects">https://stackoverflow.com/questions/2784514/sort-arraylist-of-custom-objects-by-property</a></p> <p>But here is an example program of what to do. I assumed you wanted to sort by name first, and then date. You can put logic to do that in the custom comparator.</p> <pre><code>import java.util.*; public class SortExample { public static class Student { public String name; public String date; public Student(String name, String date) { this.name = name; this.date = date; } } public static class StudentComparator implements Comparator<Student> { @Override public int compare(Student s, Student t) { int f = s.name.compareTo(t.name); return (f != 0) ? f : s.date.compareTo(t.date); } } public static void main(String args[]) { ArrayList<Student> l = new ArrayList<Student>(Arrays.asList( new Student ("x","2010-10-5"), new Student ("z","2010-10-15"), new Student ("y","2010-10-05"), new Student ("x","2010-10-1") )); System.out.println("Unsorted"); for(Student s : l) { System.out.println(s.name + " " + s.date); } Collections.sort(l, new StudentComparator()); System.out.println("Sorted"); for(Student s : l) { System.out.println(s.name + " " + s.date); } } } </code></pre> <p>Output of this is:</p> <pre><code>Unsorted x 2010-10-5 z 2010-10-15 y 2010-10-05 x 2010-10-1 Sorted x 2010-10-1 x 2010-10-5 y 2010-10-05 z 2010-10-15 </code></pre> <p><strong>EDIT</strong>: This sorts the array list in place. You'd have to copy it first if you want it as a new list.</p>

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