home | career | drupal | java | mac | mysql | perl | scala | uml | unix  

Java example source code file (RetryRunner.java)

This example Java source code file (RetryRunner.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

blockjunit4classrunner, class, frameworkmethod, initializationerror, object, override, retryrunner, statement, throwable

The RetryRunner.java Java example source code

 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *      http://www.apache.org/licenses/LICENSE-2.0
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * See the License for the specific language governing permissions and
 * limitations under the License.

package org.apache.commons.math3;

import org.junit.runners.BlockJUnit4ClassRunner;
import org.junit.runners.model.FrameworkMethod;
import org.junit.runners.model.InitializationError;
import org.junit.runners.model.Statement;

 * A test runner that retries tests when assertions fail.
public class RetryRunner extends BlockJUnit4ClassRunner {
     * Simple constructor.
     * @param testClass Class to test.
     * @throws InitializationError if default runner cannot be built.
    public RetryRunner(final Class<?> testClass)
        throws InitializationError {

    public Statement methodInvoker(final FrameworkMethod method,
                                   Object test) {
        final Statement singleTryStatement = super.methodInvoker(method, test);
        return new Statement() {
             * Evaluate the statement.
             * We attempt several runs for the test, at most MAX_ATTEMPTS.
             * if one attempt succeeds, we succeed, if all attempts fail, we
             * fail with the reason corresponding to the last attempt
            public void evaluate() throws Throwable {
                Throwable failureReason = null;

                final Retry retry = method.getAnnotation(Retry.class);
                if (retry == null) {
                    // Do a single test run attempt.
                } else {
                    final int numRetries = retry.value();

                    for (int i = 0; i < numRetries; ++i) {
                        try {
                            // Do a single test run attempt.
                            // Attempt succeeded, stop evaluation here.
                        } catch (Throwable t) {
                            // Attempt failed, store the reason.
                            failureReason = t;

                    // All attempts failed.
                    throw failureReason;

Other Java examples (source code examples)

Here is a short list of links related to this Java RetryRunner.java source code file:

my book on functional programming


new blog posts


Copyright 1998-2021 Alvin Alexander, alvinalexander.com
All Rights Reserved.

A percentage of advertising revenue from
pages under the /java/jwarehouse URI on this website is
paid back to open source projects.