Set

Elements of a set are called keys. The constructor for BasicSet is as follows:

public BasicSet(DATA_TYPE keyType, int capacity)

Parameters

• keyType: An enum declaring the type of the set.
• capacity (optional, default 0): An integer specifying the initial capacity of the set. The set will automatically double its capacity when the number of elements reaches 0.75*capacity.

1. You can add objects to a set using the add method. For example:

   BasicSet basicSet = new BasicSet(Entity.DATA_TYPE.DT_INT,4);
   basicSet.add(new BasicInt(1));

2. You can get all keys from a set using the keys method:

   public Vector keys();

   This method returns a vector (from com.xxdb.data package). You can get all the elements of the set using this vector:

   BasicSet basicSet = new BasicSet(Entity.DATA_TYPE.DT_INT);
   basicSet.add(new BasicInt(1));
   basicSet.add(new BasicInt(2));
   basicSet.add(new BasicInt(3));
   basicSet.add(new BasicInt(4));
   basicSet.add(new BasicInt(5));
   Vector vector = basicSet.keys();
   System.out.println(vector.getString());

3. You can check if a key exists in the set using the contains method, which returns a boolean value. For example:

   BasicSet basicSet = new BasicSet(Entity.DATA_TYPE.DT_INT,4);
   basicSet.add(new BasicInt(1));
   basicSet.add(new BasicInt(2));
   basicSet.add(new BasicInt(3));
   basicSet.add(new BasicInt(4));
   basicSet.add(new BasicInt(5));
   System.out.println(basicSet.contains(new BasicInt(4)));