package textbender.g.lang; // Copyright 2006-2007, Michael Allan.  Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Textbender Software"), to deal in the Textbender Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicence, and/or sell copies of the Textbender Software, and to permit persons to whom the Textbender Software is furnished to do so, subject to the following conditions: The preceding copyright notice and this permission notice shall be included in all copies or substantial portions of the Textbender Software. THE TEXTBENDER SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE TEXTBENDER SOFTWARE OR THE USE OR OTHER DEALINGS IN THE TEXTBENDER SOFTWARE.

import java.io.PrintStream;


/** A catcher of errors and exceptions.
  * <p>
  *     Subtype implementers note: if adding catch methods,
  *     bear in mind that dispatch is decided
  *     according to formal parameter type at compile time;
  *     not actual type at runtime -- unlike catch statement parameters.
  *     Best to use a new, distinct name for each new method;
  *     rather than overload the ones defined here.
  *     </p>
  */
public interface Catcher<S>
{


   // - C a t c h e r --------------------------------------------------------------------


    /** Handles an error. Implementations would normally re-throw it
      * as quickly as possible, taking care not to drop it first.
      *
      *     @param source logical source of the error
      */
    public void catchError( S source, Error r );



    /** Handles an exception.
      *
      *     @param source logical source of the exception
      */
    public void catchException( S source, Exception x );



   // ====================================================================================


    /** Catcher utilities.
      */
    public @ThreadSafe static final class X
    {

        private X() {}


        /** Prints a source indication and a stack trace, to the stream.
          */
        public static void printStackTrace( Object source, Throwable t, PrintStream stream )
        {
            String sourceString;
            try{ sourceString = source.toString(); }
            catch( Exception xS ) { sourceString = "unknown"; }
            stream.print( "CLASS " + source.getClass().getName() + "  INSTANCE "
                + sourceString + "  THREW " );
            t.printStackTrace( stream );
        }



    }


}