I have to remove duplicated objects in a List. It is a List from the object Blog that looks like this:
public class Blog {
private String title;
private String author;
private String url;
private String description;
...
}
A duplicated object is an object that have title, author, url and description equal to other object.
And I can't alter the object. I can't put new methods on it.
How do I do this?
Use set:
yourList = new ArrayList<Blog>(new LinkedHashSet<Blog>(yourList));
This will create list without duplicates and the element order will be as in original list.
Just do not forget to implement hashCode() and equals() for your class Blog.
First override equals() method:
@Override
public boolean equals(Object obj)
{
if(obj == null) return false;
else if(obj instanceof MyObject && getTitle() == obj.getTitle() && getAuthor() == obj.getAuthor() && getURL() == obj.getURL() && getDescription() == obj.getDescription()) return true;
else return false;
}
and then use:
List<MyObject> list = new ArrayList<MyObject>;
for(MyObject obj1 : list)
{
for(MyObject obj2 : list)
{
if(obj1.equals(obj2)) list.remove(obj1); // or list.remove(obj2);
}
}