title: Java TreeSet: remove and contains() not working
body: <p>I have added some simple objects to a TreeSet, but when I call the TreeSet's remove() and contains() methods, they don't work. However, when I iterate over the set the object is printed. Employee objects shall be added to the set while the objects uniqueness is based on the objects name property. The Id property is the value that should be sorted, but which is not unique.</p>
  
  <pre><code>public class Employee {
      private String name;
      private int id;
  
      public int getId() {
          return id;
      }
  
      public void setId(int id) {
          this.id = id;
      }
  
      public String getName() {
      return name;
      }
  
      public void setName(String name) {
      this.name = name;
      }
  
   // Two objects are considered equal if their names are equal
      @Override
      public boolean equals(Object o) {
      if (o == null)
          return false;
      if (this == o)
          return true; 
      if (o.getClass() == this.getClass()) {
          Employee p = ( Employee) o;
          if (p.getName() != null &amp;&amp; this.getName() != null)
          return this.getName().equals(p.getName());
          else
          return false;
      } else {
          return false;
      }
      }
  } 
  
  //*******************************************************
  
  public class EmployeeComp implements Comparator&lt;Employee&gt; {
  
      // Sort Ids, but allow duplicates, hence this function is never returning 0
      @Override
      public int compare(Employee p1, Employee p2) {
      int re = 0;
  
      boolean scoreLt = (p1.getId() &gt; p2.getId());
      boolean scoreGt = (p1.getId() &lt; p2.getId());
  
      if(scoreLt)
          re = -1;
      if(scoreGt)
          re = 1;
      else 
          re = -1;                       
           return re;                 
      }    
  }
  //*******************************************************
  // Collection shall store unique names with ordered values like:
  // Alex, 923
  // Toni, 728
  // Eddi, 232
  // Peter, 232
  // Eddi, 156  *** not allowed
  import java.util.TreeSet;
  
  
  public class Main {
      private static EmployeeComp comp = new EmployeeComp(); 
      private static TreeSet&lt;Employee&gt; employees = new TreeSet&lt;Employee&gt;(comp); 
  
      public static void main(String[] args) {
  
      Employee p1 = new Employee();
      p1.setName("Eddi");
      p1.setId(232);
  
      Employee p2 = new Employee();
      p2.setName("Toni");
      p2.setId(728);
  
      Employee p3 = new Employee();
      p3.setName("Peter");
      p3.setId(232);
  
      Employee p4 = new Employee();
      p4.setName("Alex");
      p4.setId(923);
  
      employees.add(p1);
      employees.add(p2);
      employees.add(p3);
      employees.add(p4);
  
      // Here, contains() and remove() should check the object address
      // and not perform their actions based on compareTo
  
         } 
  }
  </code></pre>