Module 5: Application Optimization

Holistic Application Optimization

Learn how to view your application as a complete system and identify optimization opportunities throughout the codebase.

Performance Profiling

Before optimizing any application, it's essential to identify where the actual bottlenecks are. Profiling tools help you measure:

• CPU usage and hot spots in your code
• Memory allocation patterns and potential leaks
• I/O and network operation timing
• Database query performance

Common Optimization Areas

Java applications can be optimized in several key areas:

• Algorithm Efficiency - Choosing appropriate data structures and algorithms
• Memory Management - Reducing unnecessary object creation and ensuring proper cleanup
• Database Access - Optimizing queries, connection pooling, and batch operations
• I/O Operations - Buffering, caching, and asynchronous operations
• Concurrency - Proper thread management and synchronization

Example: Optimizing a Data Processing Pipeline

// Before optimization
public List processCustomerData(List rawData) {
    List customers = new ArrayList<>();
    
    for (String data : rawData) {
        // Parse each record
        String[] fields = data.split(",");
        Customer customer = new Customer();
        customer.setId(Integer.parseInt(fields[0]));
        customer.setName(fields[1]);
        customer.setEmail(fields[2]);
        
        // Validate
        if (isValidEmail(customer.getEmail())) {
            // Load additional data from database
            loadPurchaseHistory(customer);
            // Process customer
            processTaxInformation(customer);
            // Add to result
            customers.add(customer);
        }
    }
    
    return customers;
}

// After optimization
public List processCustomerData(List rawData) {
    // Parallel stream for processing
    return rawData.parallelStream()
        .map(data -> {
            String[] fields = data.split(",");
            Customer customer = new Customer();
            customer.setId(Integer.parseInt(fields[0]));
            customer.setName(fields[1]);
            customer.setEmail(fields[2]);
            return customer;
        })
        .filter(customer -> isValidEmail(customer.getEmail()))
        .collect(Collectors.toList());
    
    // Batch load purchase history for all customers
    batchLoadPurchaseHistory(customers);
    
    // Process tax information in parallel
    customers.parallelStream().forEach(this::processTaxInformation);
    
    return customers;
}