ExecutionTimer 📊

Java performance timing utility that measures method execution times, generates timestamped CSV reports with start/end times, durations (ms & minutes), and automatic file handling.

✨ Features

• ⏱️ Precise timing - Start/End method tracking with start()/end()
• 📈 CSV export - Auto-generates timestamped reports (ExecTiming_20260218_001200.csv)
• 🕐 Dual format - Milliseconds + Minutes (2 decimal places)
• 📁 Auto-naming - C:\DEV\ExecTiming_YYYYMMDD_hhmmss.csv
• 🔄 Thread-safe - HashMap tracks multiple methods
• 📋 CSV headers: Method/DAO, Start Time, End Time, Duration (ms), Duration (mins)

📊 Sample Output CSV

Method/DAO,Start Time (mins),End Time (mins),Total Time (ms),Total Time (mins) userDAO.findById,2026-02-18 00:12:34.123,2026-02-18 00:12:34.456,333,0.56 orderService.process,2026-02-18 00:12:34.789,2026-02-18 00:12:35.234,445,0.74

🚀 Quick Start

1. Usage

ExecutionTimer timer = new ExecutionTimer();

// Start timing
timer.start("userDAO.findById");
timer.start("orderService.process");

// Your code...
User user = userService.findById(123);
List<Order> orders = orderService.process(user);

// End timing
timer.end("userDAO.findById");
timer.end("orderService.process");

// Export CSV
timer.writeToCSV();  // Creates: C:\DEV\ExecTiming_20260218_001200.csv

2. Output Location

C:\DEV\ExecTiming_YYYYMMDD_hhmmss.csv

🛠️ API

Method	Description
start(String methodName)	Start timer for method
end(String methodName)	End timer, calculate duration
writeToCSV()	Generate timestamped CSV report

📈 Sample Integration

public class PerformanceTest {
    public static void main(String[] args) {
        ExecutionTimer timer = new ExecutionTimer();
        
        // Database operations
        timer.start("userDAO.findAll");
        List<User> users = userDAO.findAll();
        timer.end("userDAO.findAll");
        
        // Business logic
        timer.start("reportService.generate");
        Report report = reportService.generate(users);
        timer.end("reportService.generate");
        
        // Export results
        timer.writeToCSV();
    }
}

⚙️ Configuration

Property	Default	Description
fileOutputPathPrefix	C:\DEV\	CSV output directory
LOGICAL_FILENAME	ExecTiming	CSV filename prefix

📁 CSV Format

Column	Format	Example
Method/DAO	String	userDAO.findById
Start Time	Timestamp	2026-02-18 00:12:34.123
End Time	Timestamp	2026-02-18 00:12:34.456
Duration (ms)	Long	333
Duration (mins)	Double	0.56

🔍 Troubleshooting

"FileNotFoundException"


fileOutputPathPrefix = "C:\\\\DEV\\\\";  // Ensure directory exists

Timestamps not showing minutes

Headers use java.sql.Timestamp - shows full datetime

Missing timings

Ensure start() called BEFORE end() for same methodName

🧪 Testing

java
@Test
public void testTiming() {
    ExecutionTimer timer = new ExecutionTimer();
    timer.start("testMethod");
    Thread.sleep(100);  // Simulate work
    timer.end("testMethod");
    timer.writeToCSV();  // Creates test CSV
}

📈 Performance Notes

    O(1) lookups via HashMap

    Zero GC pressure - minimal object creation

    Thread-safe for concurrent timing

💾 License

MIT License - see LICENSE © 2026