simple

Class Grep

java.lang.Object

simple.Grep

public class Grep
extends java.lang.Object

Sample continuous (streaming) grep topology application. This Java application builds a simple topology that watches a directory for files, reads each file and output lines that contain the search term. Thus as each file is added to the directory, the application will read it and output matching lines.
The application implements the typical pattern of code that declares a topology followed by submission of the topology to a Streams context com.ibm.streamsx.topology.context.StreamsContext.
This demonstrates the a continuous application and use of utility classes that produce streams.

This may be executed from the samples/java/functional directory as:

• java -cp functionalsamples.jar:../../../com.ibm.streamsx.topology/lib/com.ibm.streamsx.topology.jar:$STREAMS_INSTALL/lib/com.ibm.streams.operator.samples.jar simple.Grep CONTEXT_TYPE $HOME/books Elizabeth - Run directly from the command line.
CONTEXT_TYPE is one of:
• DISTRIBUTED - Run as an IBM Streams distributed application.
• STANDALONE - Run as an IBM Streams standalone application.
• EMBEDDED - Run embedded within this JVM.
• BUNDLE - Create an IBM Streams application bundle.
• TOOLKIT - Create an IBM Streams application toolkit.
• An application execution within your IDE once you set the class path to include the correct jars.

Constructor Summary

Constructors

Constructor and Description
Grep()

Method Summary

Modifier and Type	Method and Description
static void	main(java.lang.String[] args) Sample continuous (streaming) grep topology application.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Grep

public Grep()

Method Detail

main

public static void main(java.lang.String[] args)
                 throws java.lang.Exception

Sample continuous (streaming) grep topology application. This Java application builds a simple topology that watches a directory for files, reads each file and output lines that contain the search term. Thus as each file is added to the directory, the application will read it and output matching lines.
The application implements the typical pattern of code that declares a topology followed by submission of the topology to a Streams context com.ibm.streamsx.topology.context.StreamsContext.

Three arguments are required:

• contextType - The type of the context to execute the topology in, e.g. EMBEDDED or STANDALONE.
• directory - Directory to watch for files.
• term - Search term, if any line in a file contains term then it will be printed.

For example (classpath omitted for brevity):
java simple.Grep EMBEDDED $HOME/books Elizabeth

Throws:

java.lang.Exception