FlowLogParser is a Java application designed to process and analyze network flow logs using concurrent processing. It parses flow log files, categorizes traffic based on ports and protocols, and generates statistical reports.

1. Default Protocol Support:
   • Limited to 8 predefined protocols in default PROTOCOL_MAP:
   • Any protocol, port combination not in the map is labeled as "Untagged"
   • Custom protocol mappings can be provided via optional protocol_map_file

1. Flow Log Version:

   • Assumes VPC Flow Logs version 2 format
   • No header row in flow log file
   • Each line must contain minimum 8 fields
   • Lines with fewer than 8 fields are skipped
   • Fields are space-separated

2. Field Requirements:

   • protocol (field 8): Must be a numeric protocol identifier
   • Invalid or malformed fields result in line being skipped
   • No validation of other fields as they're not used in analysis

- Each valid line increments both tag and port-protocol counters - Duplicate lines are counted separately - "Untagged" is used when no matching tag is found in lookup table 

# Clone the repository git clone https://github.com/nachivrn/FlowLogParser.git cd FlowLogParser javac src/FlowLogParser.java -d . javac -cp .:lib/junit-platform-console-standalone-1.8.2.jar src/FlowLogParserTest.java -d . 

# Run the code # Usage: java FlowLogParser <flow_log_file> <lookup_table_file> <output_file> [protocol_map_file] java FlowLogParser ./data/flowlogfile.txt ./data/lookuptable.csv ./data/output.txt # Check output cat ./data/output.txt # Run the Unit & Functional tests java -jar lib/junit-platform-console-standalone-1.8.2.jar --class-path . --select-class FlowLogParserTest 

1. Basic Functionality Tests

   • Validates lookup table loading
   • Tests single line processing
   • Validates concurrent processing

2. Edge Cases

   • Tests duplicate entries
   • Test malformed input
   • Test empty files

3. Error Handling Tests

   • Invalid protocol numbers
   • Missing fields
   • Malformed input lines

• Tested with 100,000+ flow log records approximately 10MB and lookup table with 10,000 entries
• Measured processing time for large datasets
• Confirmed proper thread utilization