jrmsamson / file-process-concurrently

Simple java application to process a log file concurrently.

file-process-concurrently

Simple java application to process a log file concurrently.

The file should have the following format:

{"id":"scsmbstgra", "state":"STARTED", "type":"APPLICATION_LOG", "host":"12345", "timestamp":1491377495212}
{"id":"scsmbstgrb", "state":"STARTED", "timestamp":1491377495213}
{"id":"scsmbstgrc", "state":"FINISHED", "timestamp":1491377495218}
{"id":"scsmbstgra", "state":"FINISHED", "type":"APPLICATION_LOG", "host":"12345", "timestamp":1491377495217}
{"id":"scsmbstgrc", "state":"STARTED", "timestamp":1491377495210}
{"id":"scsmbstgrb", "state":"FINISHED", "timestamp":1491377495216}

Every line in the file is a JSON object containing event data:

• id: the unique event identifier
• state: whether the event was started or finished (can have values "STARTED" or "FINISHED" timestamp)
• timestamp: the timestamp of the event in milliseconds
• host: hostname (optional)
• type: type of log (optional)

This log file is supposed to be created by a server which logs different events to it. Every event has 2 entries in a log:

• one entry when the event was started
• another when the event was finished.

The entries in a log file have no specific order (it can occur that a specific event is logged before the event starts)

In the example above, the event scsmbstgrb duration is 1401377495216 - 1491377495213 = 3ms The longest event is scsmbstgrc (1491377495218 - 1491377495210 = 8ms)

The application:

• Takes the input file path as input argument
• Flags any long events that take longer than 4ms with a column in the database called "alert" Write the found event details to file-based HSQLDB (http://hsqldb.org/) in the working folder
• Creates a new table if necessary and enter the following values:
  • Event id
  • Event duration
  • Type and Host if applicable "alert" true is applicable

To test the application:

• Build the jar file by executing: ./gradlew jar

• The jar will be located in build/file-process-concurrently-1.0-SNAPSHOT.jar

• execute the jar: java -jar build/file-process-concurrently-1.0-SNAPSHOT.jar filePath [numberOfThreads]