Getting Started with Cloud Pub/Sub and the Google Cloud Client libraries

Google Cloud Pub/Sub is a fully-managed real-time messaging service that allows you to send and receive messages between independent applications. This sample Java application demonstrates how to access the Pub/Sub API using the Google Cloud Client Library for Java.

For more samples, see the samples in google-cloud-java.

Quickstart

Setup

Install Maven.
Enable Pub/Sub API.
Set up authentication.

Build

Build your project with:

  mvn clean package -DskipTests

Create a new topic

  mvn exec:java -Dexec.mainClass=com.example.pubsub.CreateTopicExample -Dexec.args=my-topic

Create a subscription

  mvn exec:java -Dexec.mainClass=com.example.pubsub.CreatePullSubscriptionExample -Dexec.args="my-topic my-sub"

Publish messages

  mvn exec:java -Dexec.mainClass=com.example.pubsub.PublisherExample -Dexec.args="my-topic 5"

Publishes 5 messages to the topic my-topic.

Receive messages

   mvn exec:java -Dexec.mainClass=com.example.pubsub.SubscriberExample -Dexec.args=my-sub

Subscriber will continue to listen on the topic and print out message id and data as messages are received. Press Ctrl+C to exit the application.

Testing

Run the test with Maven.

  mvn verify