Package org.sqlite.date

Class ExceptionUtils

  • public class ExceptionUtils
extends Object
    Provides utilities for manipulating and examining Throwable objects.
    Since:
    1.0

    • Constructor Detail

      • ExceptionUtils

        public ExceptionUtils()

    • Method Detail

      • rethrow

        public static <R> R rethrow​(Throwable throwable)
        Throw a checked exception without adding the exception to the throws clause of the calling method. This method prevents throws clause pollution and reduces the clutter of "Caused by" exceptions in the stacktrace.

        The use of this technique may be controversial, but exceedingly useful to library developers. public int propagateExample { // note that there is no throws clause try { return invocation(); // throws IOException } catch (Exception e) { return ExceptionUtils.rethrow(e); // propagates a checked exception } }

        This is an alternative to the more conservative approach of wrapping the checked exception in a RuntimeException: public int wrapExample { // note that there is no throws clause try { return invocation(); // throws IOException } catch (Error e) { throw e; } catch (RuntimeException e) { throw e; // wraps a checked exception } catch (Exception e) { throw new UndeclaredThrowableException(e); // wraps a checked exception } }

        One downside to using this approach is that the java compiler will not allow invoking code to specify a checked exception in a catch clause unless there is some code path within the try block that has invoked a method declared with that checked exception. If the invoking site wishes to catch the shaded checked exception, it must either invoke the shaded code through a method re-declaring the desired checked exception, or catch Exception and use the instanceof operator. Either of these techniques are required when interacting with non-java jvm code such as Jython, Scala, or Groovy, since these languages do not consider any exceptions as checked.

        Parameters:
        throwable - The throwable to rethrow.
        Returns:
        R Never actually returns, this generic type matches any type which the calling site requires. "Returning" the results of this method, as done in the propagateExample above, will satisfy the java compiler requirement that all code paths return a value.
        Throws:
        throwable
        Since:
        3.5