Package org.apache.jena.sparql.engine.join

Class JoinKey

  • All Implemented Interfaces:
    java.lang.Iterable<Var>
    public final class JoinKey
extends java.lang.Object
implements java.lang.Iterable<Var>
    JoinKey for hash joins

    • Nested Class Summary

      Nested Classes 
      Modifier and Type Class Description
      static class  JoinKey.Builder
      The builder can emit a key every time build() is caller and it can be continued to be used.

    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      static JoinKey create​(java.util.Collection<Var> vars1, java.util.Collection<Var> vars2)
      Make a JoinKey from the intersection of two sets
      static JoinKey create​(Var var)  
      static JoinKey createVarKey​(java.util.Collection<Var> vars1, java.util.Collection<Var> vars2)
      Make a JoinKey of single variable from the intersection of two sets
      Var getVarKey()
      Get a single variable for this key.
      boolean isEmpty()  
      java.util.Iterator<Var> iterator()  
      int length()  
      java.lang.String toString()  

      • Methods inherited from class java.lang.Object

        equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

      • Methods inherited from interface java.lang.Iterable

        forEach, spliterator

    • Method Detail

      • create

        public static JoinKey create​(java.util.Collection<Var> vars1,
                             java.util.Collection<Var> vars2)
        Make a JoinKey from the intersection of two sets

      • createVarKey

        public static JoinKey createVarKey​(java.util.Collection<Var> vars1,
                                   java.util.Collection<Var> vars2)
        Make a JoinKey of single variable from the intersection of two sets

      • create

        public static JoinKey create​(Var var)

      • isEmpty

        public boolean isEmpty()

      • length

        public int length()

      • getVarKey

        public Var getVarKey()
        Get a single variable for this key. For any one key, it always returns the same var

      • iterator

        public java.util.Iterator<Var> iterator()
        Specified by:
        iterator in interface java.lang.Iterable<Var>

      • toString

        public java.lang.String toString()
        Overrides:
        toString in class java.lang.Object