Sort an ArrayList based on an object field [duplicate]

Possible Duplicate:
Sorting an ArrayList of Contacts

I am storing DataNode objects in an ArrayList. The DataNode class has an integer field called degree. I want to retrieve DataNode objects from nodeList in the increasing order of degree. How can I do it.

List<DataNode> nodeList = new ArrayList<DataNode>();

Solution 1:

Use a custom comparator:

Collections.sort(nodeList, new Comparator<DataNode>(){
     public int compare(DataNode o1, DataNode o2){
         if(o1.degree == o2.degree)
             return 0;
         return o1.degree < o2.degree ? -1 : 1;
     }
});

Solution 2:

Modify the DataNode class so that it implements Comparable interface.

public int compareTo(DataNode o)
{
     return(degree - o.degree);
}

then just use

Collections.sort(nodeList);