locksdemo.RedisServer.java Source code

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Here is the source code for locksdemo.RedisServer.java

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/*
 * Copyright 2012-2014 the original author or authors.
 *
 * Licensed 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,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package locksdemo;

import static org.junit.Assert.fail;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.junit.Assume;
import org.junit.rules.TestRule;
import org.junit.runner.Description;
import org.junit.runners.model.Statement;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.connection.jedis.JedisConnectionFactory;

/**
 * @author Eric Bottard
 * @author Gary Russell
 * @author Dave Syer
 */
public class RedisServer implements TestRule {

    private static final String EXTERNAL_SERVERS_REQUIRED = "EXTERNAL_SERVERS_REQUIRED";

    protected JedisConnectionFactory resource;

    private final String resourceDescription = "Redis ConnectionFactory";

    private static final Log logger = LogFactory.getLog(RedisServer.class);

    public static RedisServer running() {
        return new RedisServer();
    }

    private RedisServer() {
    }

    @Override
    public Statement apply(final Statement base, Description description) {
        try {
            this.resource = obtainResource();
        } catch (Exception ex) {
            maybeCleanup();
            return failOrSkip(ex);
        }

        return new Statement() {

            @Override
            public void evaluate() throws Throwable {
                try {
                    base.evaluate();
                } finally {
                    try {
                        cleanupResource();
                    } catch (Exception ignored) {
                        RedisServer.logger.warn("Exception while trying to cleanup proper resource", ignored);
                    }
                }
            }

        };
    }

    private Statement failOrSkip(Exception exception) {
        String serversRequired = System.getenv(EXTERNAL_SERVERS_REQUIRED);
        if ("true".equalsIgnoreCase(serversRequired)) {
            logger.error(this.resourceDescription + " IS REQUIRED BUT NOT AVAILABLE", exception);
            fail(this.resourceDescription + " IS NOT AVAILABLE");
            // Never reached, here to satisfy method signature
            return null;
        } else {
            logger.error(this.resourceDescription + " IS NOT AVAILABLE, SKIPPING TESTS", exception);
            return new Statement() {

                @Override
                public void evaluate() throws Throwable {
                    Assume.assumeTrue(
                            "Skipping test due to " + RedisServer.this.resourceDescription + " not being available",
                            false);
                }
            };
        }
    }

    private void maybeCleanup() {
        if (this.resource != null) {
            try {
                cleanupResource();
            } catch (Exception ignored) {
                logger.warn("Exception while trying to cleanup failed resource", ignored);
            }
        }
    }

    public RedisConnectionFactory getResource() {
        return this.resource;
    }

    /**
     * Perform cleanup of the {@link #resource} field, which is guaranteed to be non null.
     *
     * @throws Exception any exception thrown by this method will be logged and swallowed
     */
    protected void cleanupResource() throws Exception {
        this.resource.destroy();
    }

    /**
     * Try to obtain and validate a resource. Implementors should either set the
     * {@link #resource} field with a valid resource and return normally, or throw an
     * exception.
     */
    protected JedisConnectionFactory obtainResource() throws Exception {
        JedisConnectionFactory resource = new JedisConnectionFactory();
        resource.afterPropertiesSet();
        resource.getConnection().close();
        return resource;
    }

}