Overview (Java Functional Samples)
Date: 2020-08-07

Sample applications and use of the Java topology API for IBM Streams.

See: Description

Packages
Package | Description
--- | ---
bluemix |
games |
kafka | A sample demonstrating integration with the Apache Kafka messaging system http://kafka.apache.org.
mqtt | A sample demonstrating integration with the MQTT messaging system http://mqtt.org.
parallel | Samples using parallel streams.
rest | Samples using Java REST api wrappers
simple | Basic, simple samples of Java streaming applications.
state | Sample use of functional logic with state that persists across invocations.
topic | Topic based Publish-Subscribe sample Java applications.
twitter | Sample how how to process tweets using Java.
vwap | SPL sample Vwap application reimplemented using Java.

Sample applications and use of the Java topology API for IBM Streams.

### Sample Streaming Applications

Sample | Description | Focus
--- | --- | ---
`HelloWorld` | Prints Hello World! to standard output. | Basic mechanics of declaring a topology and executing it.
`Echo` | Echos command line arguments to standard out. | Passing in runtime values to a topology.
`FilterEcho` | Echos a subset of command line arguments to standard out | Use of Java functional programming style for filtering.
`Grep` | Continually watches a directory, reads new files in the directory and prints lines from the files containing a search term to standard out | Use of utility methods provided by the Java topology API.
`TwitterTrending` | Reads tweets from a specified directory and calculates the trending hashtags in parallel. | A real-world usage for windowing.
`RegexGrep` | Continually watches a directory, reads new files in the directory and prints lines from the files that match a regular expression to standard out | Java functional programming using an anonymous class with initialization.
`Vwap` | SPL Vwap sample reimplemented in Java. | Java objects as tuples, integration with SPL operators and tuples.
`PublishBeacon`,`SubscribeBeacon` | Publish-subscribe model for streams across applications | Publish-subscribe in distributed.
`KafkaSample` | Publishes messages to a Kafka topic. Subscribes to a Kafka topic and prints results. | Integrating with Apache Kafka.
`MqttSample` | Publishes messages to a MQTT topic. Subscribes to a MQTT topic and prints results. | Integrating with MQTT.