I am trying to implement a Binary Tree  class.Here's the insert method.When I compile it I get an error as "uses unchecked or unsafe operations.Recompile with -Xlint:unchecked for details". Can some on please tell me how I can correct this?  public class BinaryNode{     Comparable element;     BinaryNode left;     BinaryNode right;     BinaryNode(Comparable theElement,BinaryNode lt,BinaryNode rt){         element=theElement;         left=lt;         right=rt;            }     BinaryNode(Comparable theElement){         this(theElement,null,null);     }  }   public class BinaryTr  {     private BinaryNode root;     BinaryTr(){         root=null;     }     public void insert(Comparable x){         root=insert(root,x);     }     public BinaryNode insert(BinaryNode current,Comparable x){         if (current==null)             current=new BinaryNode(x);         else{             if(current.element.compareTo(x)&gt;0)                 current.left=insert(current.left,x);         else if (current.element.compareTo(x)&lt;0)             current.right=insert(current.right,x);         else{             System.out.println("Duplicates not allowed");         }     }     return current; }  public static void main (String args[]){     BinaryTr t=new BinaryTr();     t.insert(5);             t.insert(4);             t.insert(5);     } }
For example:  javac Foo.java Note: Foo.java uses unchecked or unsafe operations. Note: Recompile with -Xlint:unchecked for details.
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