How to make a loop with List Iterator...

[Krassi Bogdanova]

Hi all,
I have one Vector with result and I want to compare the first Element of the List with the next, and if the next is equal to first the next must be remove, but i dont know how?
Please help me!
Vector ligne = (Vector)result.elementAt(row);
List list= new ArrayList();
list.add(ligne.firstElement());
for (ListIterator i = list.listIterator(); i.hasNext(); ) {
String temp= (String)i.next();
String index= (String)i.previous();
if (index==null ? i.next()==null : index.equals(i.next())) {
i.remove();

[Manfred Leonhardt]

Hi Krassi,
The code below should work using iterators.

    //
    // Remove any duplicates that might exist.
    //
    for( int i = 0; i < results.size(); ++i )
    {
      Iterator itr = results.iterator();
      //
      // Get to correct starting object
      //
      int j = 0;
      while( itr.hasNext() && j++ <= i )
      {
        ob1 = itr.next();
      }
      //
      // Compare starting object with all rest of collection.
      //
      while( itr.hasNext() )
      {
        if( itr.next().equals( ob1 ) )
        {
          itr.remove();
        }
      }
    }

Regards,
Manfred.

[Krassi Bogdanova]

Thanks Manfred,
the code remove all elements and I want display all elements without duplicates.
This Vector is the result of one Select and I dont know how many elemnts I will have and after the test if there exists duplicates I must print the result + the result of the SELECT.

[Jamie Robertson]

you could do this:

Set h = new HashSet( result ); //

h will contain all the unique elements in result. Or if you have a 2D Vector ( Vector of Vectors ) then you do something like:

Vector uniqueResults = new Vector();
Iterator i = result.iterator();
while (i.hasNext()) 
{
   Set h = new HashSet( (Vector)i.next() );
   uniqueResults.add( h );
}

you will end up with a Vector of Sets containing only the unique items of the Original Vector.
Jamie

[Manfred Leonhardt]

Hi,
I like Jamies' choice better. But just to set the record straight the following code DOES end up with unique elements of the vector.

  public static void main( String[] args ) throws Exception
  {
    Object ob1 = null;
    //
    // Create vector with results in it.
    //
    Vector results = new Vector();
    results.add( new Integer( 5 ) );
    results.add( new Integer( 7 ) );
    results.add( new Integer( 2 ) );
    results.add( new Integer( 3 ) );
    results.add( new Integer( 5 ) );
    results.add( new Integer( 2 ) );
    results.add( new Integer( 5 ) );
    results.add( new Integer( 1 ) );
    System.out.println( "Before: " + results );
    //
    // Remove any duplicates that might exist.
    //
    for( int i = 0; i < results.size(); ++i )
    {
      Iterator itr = results.iterator();
      int j = 0;
      while( itr.hasNext() && j++ <= i )
      {
        ob1 = itr.next();
      }
      while( itr.hasNext() )
      {
        if( itr.next().equals( ob1 ) )
        {
          itr.remove();
        }
      }
    }
    System.out.println( "After: " + results );
  }

Regards,
Manfred.

[Krassi Bogdanova]

Thanks again,
but my results is :
Vector results = new Vector();
[LABA001]After: [LABA001] - Vector
[LABA001]After: [LABA001] - next Vector
[LABA002]After: [LABA002] - next Vector
[LABA003]After: [LABA003] - next Vector
[LABA003]After: [LABA003] - next Vector
and I don't know how to compaire the first Vector with the next etc.