RestApplication.java

package com.hubspot.bootstrap.rest;

import java.util.Arrays;
import java.util.function.Consumer;

import com.google.inject.Module;
import com.hubspot.dropwizard.guicier.GuiceBundle;

import io.dropwizard.Application;
import io.dropwizard.Bundle;
import io.dropwizard.ConfiguredBundle;
import io.dropwizard.setup.Bootstrap;
import io.dropwizard.setup.Environment;

public class RestApplication extends Application<DefaultConfiguration> {
  private final Consumer<Bootstrap<DefaultConfiguration>> bootstrapModifier;

  private RestApplication(Consumer<Bootstrap<DefaultConfiguration>> bootstrapModifier) {
    this.bootstrapModifier = bootstrapModifier;
  }

  public static Builder newBuilder() {
    return new Builder(GuiceBundle.defaultBuilder(DefaultConfiguration.class));
  }

  @Override
  public void initialize(Bootstrap<DefaultConfiguration> bootstrap) {
    bootstrapModifier.accept(bootstrap);
  }

  @Override
  public void run(DefaultConfiguration configuration, Environment environment) {}

  public static class Builder {
    private final GuiceBundle.Builder<DefaultConfiguration> guiceBundle;
    private Consumer<Bootstrap<DefaultConfiguration>> bootstrapModifier;

    private Builder(GuiceBundle.Builder<DefaultConfiguration> guiceBundle) {
      this.guiceBundle = guiceBundle;
      this.bootstrapModifier = bootstrap -> bootstrap.addBundle(guiceBundle.build());
    }

    public final Builder modules(Module... modules) {
      guiceBundle.modules(modules);
      return this;
    }

    public final Builder bundles(Bundle... bundles) {
      return bootstrapModifier(bootstrap -> Arrays.asList(bundles).forEach(bootstrap::addBundle));
    }

    @SafeVarargs
    public final Builder bundles(ConfiguredBundle<DefaultConfiguration>... bundles) {
      return bootstrapModifier(bootstrap -> Arrays.asList(bundles).forEach(bootstrap::addBundle));
    }

    public final Builder bootstrapModifier(Consumer<Bootstrap<DefaultConfiguration>> bootstrapModifier) {
      this.bootstrapModifier = this.bootstrapModifier.andThen(bootstrapModifier);
      return this;
    }

    public Application<DefaultConfiguration> build() {
      return new RestApplication(bootstrapModifier);
    }
  }
}

RestApplication2.java

package com.hubspot.bootstrap.rest;

import java.util.Arrays;
import java.util.function.Consumer;

import com.google.inject.Module;
import com.hubspot.dropwizard.guicier.GuiceBundle;

import io.dropwizard.Application;
import io.dropwizard.Bundle;
import io.dropwizard.ConfiguredBundle;
import io.dropwizard.setup.Bootstrap;
import io.dropwizard.setup.Environment;

public class RestApplication2<T extends DefaultConfiguration> extends Application<T> {
  private final Class<T> configurationClass;
  private final Consumer<Bootstrap<T>> bootstrapModifier;

  private RestApplication2(Class<T> configurationClass, Consumer<Bootstrap<T>> bootstrapModifier) {
    this.configurationClass = configurationClass;
    this.bootstrapModifier = bootstrapModifier;
  }

  public static Builder newBuilder() {
    return newBuilder(DefaultConfiguration.class);
  }
  
  public static <T extends DefaultConfiguration> Builder newBuilder(Class<T> configurationClass) {
    return new Builder<>(configurationClass, GuiceBundle.defaultBuilder(configurationClass));
  }

  @Override
  public Class<T> getConfigurationClass() {
    return configurationClass;
  }

  @Override
  public void initialize(Bootstrap<T> bootstrap) {
    bootstrapModifier.accept(bootstrap);
  }

  @Override
  public void run(T configuration, Environment environment) {}

  public static class Builder<T extends DefaultConfiguration> {
    private final Class<T> configurationClass;
    private final GuiceBundle.Builder<T> guiceBundle;
    private Consumer<Bootstrap<T>> bootstrapModifier;

    private Builder(Class<T> configurationClass, GuiceBundle.Builder<T> guiceBundle) {
      this.configurationClass = configurationClass;
      this.guiceBundle = guiceBundle;
      this.bootstrapModifier = bootstrap -> bootstrap.addBundle(guiceBundle.build());
    }

    public final Builder modules(Module... modules) {
      guiceBundle.modules(modules);
      return this;
    }

    public final Builder bundles(Bundle... bundles) {
      return bootstrapModifier(bootstrap -> Arrays.asList(bundles).forEach(bootstrap::addBundle));
    }

    @SafeVarargs
    public final Builder bundles(ConfiguredBundle<? super T>... bundles) {
      return bootstrapModifier(bootstrap -> Arrays.asList(bundles).forEach(bootstrap::addBundle));
    }

    public final Builder bootstrapModifier(Consumer<Bootstrap<T>> bootstrapModifier) {
      this.bootstrapModifier = this.bootstrapModifier.andThen(bootstrapModifier);
      return this;
    }

    public Application<T> build() {
      return new RestApplication2<>(configurationClass, bootstrapModifier);
    }
  }
}