Package com.teracloud.streams.topology.context

package com.teracloud.streams.topology.context

Context for executing Streams Java topologies.

Submission/Execution

There are four (primary) mechanisms to submit or execute a Java topology:

• StreamsContext.Type.DISTRIBUTED - The topology is compiled into a Streams application bundle and submitted to a Streams instance.
• StreamsContext.Type.BUNDLE - The topology is compiled into a Streams application bundle which can then be submitted to a Streams instance.
• StreamsContext.Type.STANDALONE - The topology is compiled into a Streams application standalone bundle and executed as a separate child process of the Java virtual machine.
• StreamsContext.Type.EMBEDDED - The topology is executed using the Java Streams runtime, embedded within the Java virtual machine.

For a full list of the supported types of StreamsContext see StreamsContext.Type.

SPL Compilation and Integration

When a Streams application bundle is produced, then the SPL compiler sc is used to produce the bundle (sab file). The toolkit path for compilation is:

1. The generated application toolkit containing the generated SPL code for the topology.
2. The com.teracloud.streams.topology toolkit (its location is auto-discovered).
3. Toolkits added by SPL.addToolkit(TopologyElement, File) .
4. The value of the environment variable STREAMS_SPLPATH if it is set.
5. The toolkits from the Streams product: $STREAMS_INSTALL/toolkits.

Related Packages

Package	Description
com.teracloud.streams.topology	Java application API for Streams.

Class	Description
ContextProperties	Properties that can be specified when submitting the topology to a context.
JobProperties	Job properties specific to distributed contexts.
Placeable<T extends Placeable<T>>	Placement directives for a topology element when executing in a distributed runtime.
ResultProperties	Result properties.
StreamsContext<T>	A StreamsContext provides the ability to turn a Topology into an executable.
StreamsContext.Type	Types of the Streams context that a Topology can be executed against.
StreamsContextFactory	Factory for creating StreamsContext instances.