package bluej.stride.framedjava.ast.links;

import bluej.stride.framedjava.slots.UnderlineContainer;
import threadchecker.OnThread;
import threadchecker.Tag;




| A possible link is an item in a slot which could be a hyper link to:
|  - a declared method (subclass: {}link PossibleMethodUseLink})
|  - a superclass method (subclass: {}link PossibleKnownMethodLink})
|  - a type (subclass: {}link PossibleTypeLink})
|  - a variable (subclass: {}link PossibleVarLink})
|
|  It's created by the slots, where we know which things *could* be a link,
|  but we don't know for sure (e.g. this looks like a variable, but it could
|  be undeclared, or it could be a method missing parameters, or it could
|  be somewhere that we don't currently detect, e.g. a protected field in
|  a superclass).  So we create a PossibleLink object with the details,
|  which will then be inspected in the editor and it will be confirmed or not.
|
public abstract class PossibleLink
{       


| The start position within the slot, 0 is before the first char
|
protected final int startPosition;
   
   

| The start position within the slot, 1 is after the first char
|
protected final int endPosition;
   
   

| The slot which this possible link is in
|
protected final UnderlineContainer slot;
   
   

| Whether this link finding request has been cancelled.
| Generally, possible links are created and searched when the
| user is mousing around while holding a modifier key.  If
| they mouse out of a link, it will be cancelled.
|
private boolean cancelled;

   
   public PossibleLink(int startPosition, int endPosition, UnderlineContainer slot)
   {        
      this.startPosition = startPosition;
       
      this.endPosition = endPosition;
       
      this.slot = slot;     
      }

   @OnThread(Tag.FX)
   
   public synchronized void cancel()
   {        
      cancelled = true;     
      }

   @OnThread(Tag.Any)
   
   protected synchronized boolean isCancelled()
   {        
      return cancelled;     
      }

   
   public int getEndPosition()
   {        
      return endPosition;     
      }

   
   public int getStartPosition()
   {        
      return startPosition;     
      }

   
   public UnderlineContainer getSlot()
   {        
      return slot;     
      } 
   }