001package votorola.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 "Votorola Software"), to deal in the Votorola Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicence, and/or sell copies of the Votorola Software, and to permit persons to whom the Votorola 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 Votorola Software. THE VOTOROLA 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 VOTOROLA SOFTWARE OR THE USE OR OTHER DEALINGS IN THE VOTOROLA SOFTWARE. 002 003import java.io.PrintStream; 004 005 006/** A catcher of errors and exceptions. 007 * 008 * <p>Subtype implementers note: if adding catch methods, bear in mind that dispatch is 009 * decided according to formal parameter type at compile time; not actual type at runtime 010 * - unlike catch statement parameters. Best to use a new, distinct name for each new 011 * method; rather than overload the ones defined here.</p> 012 */ 013public interface Catcher<S> 014{ 015 016 017 // - C a t c h e r -------------------------------------------------------------------- 018 019 020 /** Handles an error. Implementations would normally re-throw it as quickly as 021 * possible, taking care not to drop it first. 022 * 023 * @param source The logical source of the error. 024 */ 025 public void catchError( S source, Error r ); 026 027 028 029 /** Handles an exception. 030 * 031 * @param source The logical source of the exception. 032 */ 033 public void catchException( S source, Exception x ); 034 035 036 037 // ==================================================================================== 038 039 040 /** Catcher utilities. 041 */ 042 public @ThreadSafe static final class U 043 { 044 045 private U() {} 046 047 048 /** Prints a source indication and a stack trace, to the stream. 049 */ 050 public static void printStackTrace( final Object source, final Throwable t, 051 final PrintStream stream ) 052 { 053 String s; 054 try{ s = source.toString(); } 055 catch( Exception xS ) { s = "unknown"; } 056 stream.print( "CLASS " + source.getClass().getName() + " INSTANCE " + s + " THREW " ); 057 t.printStackTrace( stream ); 058 } 059 060 061 } 062 063 064}