jhalterman

  public static <T> T getWithDcl(Supplier<T> supplier, Supplier<T> factory, Object mutex) {
    T object = supplier.get();
    if (object == null) {
      synchronized (mutex) {
        object = supplier.get();
        if (object == null) {
          object = factory.get();
        }
      }
    }

jhalterman

import io.dropwizard.Application;
import io.dropwizard.Configuration;
import io.dropwizard.cli.ServerCommand;
import io.dropwizard.lifecycle.ServerLifecycleListener;
import io.dropwizard.setup.Bootstrap;
import io.dropwizard.setup.Environment;
import io.dropwizard.testing.junit.ConfigOverride;

import java.util.Enumeration;

jhalterman

import io.dropwizard.Configuration;
import io.dropwizard.configuration.ConfigurationFactory;
import io.dropwizard.jackson.Jackson;
import io.dropwizard.jersey.DropwizardResourceConfig;
import io.dropwizard.jersey.jackson.JacksonMessageBodyProvider;
import io.dropwizard.logging.LoggingFactory;
import io.dropwizard.setup.Environment;

import java.io.File;
import java.io.FileNotFoundException;

jhalterman

/**
 * A waiter where waiting threads can be interrupted (as opposed to awakened).
 * 
 * @author Jonathan Halterman
 */
public class InterruptableWaiter {
  private final Sync sync = new Sync();

  private static final class Sync extends AbstractQueuedSynchronizer {
    private static final long serialVersionUID = 4016766900138538852L;

jhalterman

/**
 * A circuit that accepts re-entrant {@link #open()} and {@link #close()} calls and ensures fairness
 * when releasing {@link #await() waiting} threads.
 * 
 * @author Jonathan Halterman
 */
public class ReentrantCircuit {
  private final Sync sync = new Sync();

  /**