com.hp.hpl.jena.sparql.algebra.op
Class OpExt

java.lang.Object
  extended by com.hp.hpl.jena.sparql.util.PrintSerializableBase
      extended by com.hp.hpl.jena.sparql.algebra.op.OpBase
          extended by com.hp.hpl.jena.sparql.algebra.op.OpExt
All Implemented Interfaces:
Op, Named, PrintSerializable, Printable
Direct Known Subclasses:
OpFetch

public abstract class OpExt
extends OpBase

Marker for extension points Execution will be per-engine specific


Constructor Summary
OpExt(String name)
           
 
Method Summary
abstract  Op effectiveOp()
          Return an op that will used by query processing algorithms such as optimization.
abstract  QueryIterator eval(QueryIterator input, ExecutionContext execCxt)
          Evaluate the op, given a stream of bindings as input Throw UnsupportedOperationException if this OpExt is not executeable.
 String getName()
           
 void output(IndentedWriter out, SerializationContext sCxt)
           
abstract  void outputArgs(IndentedWriter out, SerializationContext sCxt)
          Output the arguments in legal SSE format.
 void visit(OpVisitor opVisitor)
           
 
Methods inherited from class com.hp.hpl.jena.sparql.algebra.op.OpBase
equals, equalTo, hashCode, output
 
Methods inherited from class com.hp.hpl.jena.sparql.util.PrintSerializableBase
toString, toString
 
Methods inherited from class java.lang.Object
getClass, notify, notifyAll, wait, wait, wait
 
Methods inherited from interface com.hp.hpl.jena.sparql.util.PrintSerializable
toString
 

Constructor Detail

OpExt

public OpExt(String name)
Method Detail

effectiveOp

public abstract Op effectiveOp()
Return an op that will used by query processing algorithms such as optimization. This method returns a non-extension Op expression that is the equivalent SPARQL expression. For example, this is the Op replaced by this extension node.


eval

public abstract QueryIterator eval(QueryIterator input,
                                   ExecutionContext execCxt)
Evaluate the op, given a stream of bindings as input Throw UnsupportedOperationException if this OpExt is not executeable.


getName

public final String getName()

visit

public final void visit(OpVisitor opVisitor)

output

public void output(IndentedWriter out,
                   SerializationContext sCxt)
Specified by:
output in interface PrintSerializable
Overrides:
output in class OpBase

outputArgs

public abstract void outputArgs(IndentedWriter out,
                                SerializationContext sCxt)
Output the arguments in legal SSE format. Multiple items, whitespace separated



Licenced under the Apache License, Version 2.0