Dépôt officiel du code source de l'ERP OpenConcerto

/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 * 
 * Copyright 2011 OpenConcerto, by ILM Informatique. All rights reserved.
 * 
 * The contents of this file are subject to the terms of the GNU General Public License Version 3
 * only ("GPL"). You may not use this file except in compliance with the License. You can obtain a
 * copy of the License at http://www.gnu.org/licenses/gpl-3.0.html See the License for the specific
 * language governing permissions and limitations under the License.
 * 
 * When distributing the software, include this License Header Notice in each file.
 */
 
 package org.openconcerto.utils.cc;

import java.util.concurrent.ExecutionException;
import java.util.concurrent.FutureTask;

public class ExceptionFuture<V, X extends Exception, X2 extends Exception> extends FutureTask<V> {

    static public class OneExceptionFuture<V, X extends Exception> extends ExceptionFuture<V, X, RuntimeException> {
        public <X2 extends RuntimeException> OneExceptionFuture(final I2ExnFactory<? extends V, ? extends X, ? extends RuntimeException> cl) {
            super(cl, RuntimeException.class);
        }
    }

    private final Class<X2> exnClass;

    public ExceptionFuture(final I2ExnFactory<? extends V, ? extends X, ? extends X2> cl, final Class<X2> exnClass) {
        super(cl::createChecked);
        this.exnClass = exnClass;
    }

    public final V getWithOriginalException() throws InterruptedException, X, X2 {
        try {
            return this.get();
        } catch (ExecutionException e) {
            final Throwable cause = e.getCause();
            if (cause instanceof Error) {
                throw (Error) cause;
            } else if (cause instanceof RuntimeException) {
                throw (RuntimeException) cause;
                // Not strictly necessary but it feels more robust than to cast "cause" to X even
                // when it's really X2
            } else if (this.exnClass.isInstance(cause)) {
                throw this.exnClass.cast(cause);
            } else {
                // our Callable throws X or X2 but the latter is already handled above.
                @SuppressWarnings("unchecked")
                final X casted = (X) cause;
                throw casted;
            }
        }
    }
}