title: LinkedHashSet is not Removing Duplicates
body: <p>I am using LinkedHashSet for removing duplicated entries. But for below custom model the Set still keeps duplicate entries. Please help me to find the bugs. Is there anything wrong with overriding equals method. For your kind information i only treats two node equals when their phone, type and status are same.</p>
  
  <pre><code>public class BlockNode { 
      public int id;
      public int type;
      public int status;
      public String phone;
      public String date;
      public String content;
  
      @Override
      public boolean equals(Object o) {
          return this.toString().equals(((BlockNode)o).toString());
      }
  
      @Override
      public String toString() {
          return "number:" + phone + " type:" + type + " status:" + status + "\n"; 
      }
  }
  </code></pre>