content: package com.example.service;
  
  import java.util.*;
  import java.time.LocalDateTime;
  import java.time.format.DateTimeFormatter;
  import java.sql.Connection;
  import java.sql.PreparedStatement;
  import java.sql.ResultSet;
  import java.sql.SQLException;
  import javax.sql.DataSource;
  
  /**
   * BigService - Large-scale business service class
   * This class contains various business logic.
   * Contains approximately 1000 lines of code for demonstration purposes.
   */
  public class BigService {
  
      private static final String DEFAULT_ENCODING = "UTF-8";
      private static final int MAX_RETRY_COUNT = 3;
      private static final long TIMEOUT_MILLISECONDS = 30000;
      private static final String DATE_FORMAT = "yyyy-MM-dd HH:mm:ss";
  
      private DataSource dataSource;
      private Map<String, Object> configurationCache;
      private List<String> activeConnections;
      private Set<String> validatedUsers;
      private Queue<String> pendingOperations;
  
      /**
       * Constructor
       */
      public BigService() {
          this.configurationCache = new HashMap<>();
          this.activeConnections = new ArrayList<>();
          this.validatedUsers = new HashSet<>();
          this.pendingOperations = new LinkedList<>();
          initializeService();
      }
  
      /**
       * Service initialization
       */
      private void initializeService() {
          System.out.println("Initializing BigService...");
          loadConfiguration();
          setupDatabaseConnection();
          validateSystemRequirements();
          System.out.println("BigService initialization completed.");
      }
  
      /**
       * Load configuration
       */
      private void loadConfiguration() {
          configurationCache.put("max_connections", 100);
          configurationCache.put("timeout", TIMEOUT_MILLISECONDS);
          configurationCache.put("retry_count", MAX_RETRY_COUNT);
          configurationCache.put("encoding", DEFAULT_ENCODING);
          configurationCache.put("date_format", DATE_FORMAT);
  
          for (int i = 0; i < 10; i++) {
              configurationCache.put("config_param_" + i, "value_" + i);
          }
      }
  
      /**
       * Database connection setup
       */
      private void setupDatabaseConnection() {
          System.out.println("Setting up database connection...");
          // Dummy connection setup process
          for (int i = 0; i < 5; i++) {
              activeConnections.add("connection_" + i);
              System.out.println("Created connection: connection_" + i);
          }
      }
  
      /**
       * System requirements validation
       */
      private void validateSystemRequirements() {
          System.out.println("Validating system requirements...");
          checkMemoryUsage();
          checkDiskSpace();
          checkNetworkConnectivity();
          System.out.println("System requirements validation completed.");
      }
  
      /**
       * Memory usage check
       */
      private void checkMemoryUsage() {
          Runtime runtime = Runtime.getRuntime();
          long totalMemory = runtime.totalMemory();
          long freeMemory = runtime.freeMemory();
          long usedMemory = totalMemory - freeMemory;
  
          System.out.println("Total Memory: " + totalMemory);
          System.out.println("Free Memory: " + freeMemory);
          System.out.println("Used Memory: " + usedMemory);
  
          if (usedMemory > totalMemory * 0.8) {
              System.out.println("WARNING: High memory usage detected!");
          }
      }
  
      /**
       * Disk space check
       */
      private void checkDiskSpace() {
          System.out.println("Checking disk space...");
          // Dummy disk space check
          for (int i = 0; i < 3; i++) {
              System.out.println("Disk " + i + ": Available space OK");
          }
      }
  
      /**
       * Network connectivity check
       */
      private void checkNetworkConnectivity() {
          System.out.println("Checking network connectivity...");
          String[] hosts = {"localhost", "database.example.com", "api.example.com"};
  
          for (String host : hosts) {
              System.out.println("Testing connection to: " + host);
              // Dummy connection test
              try {
                  Thread.sleep(100);
                  System.out.println("Connection to " + host + " successful");
              } catch (InterruptedException e) {
                  System.out.println("Connection test interrupted");
              }
          }
      }
  
      /**
       * User authentication
       */
      public boolean authenticateUser(String username, String password) {
          if (username == null || username.isEmpty()) {
              System.out.println("ERROR: Username is null or empty");
              return false;
          }
  
          if (password == null || password.isEmpty()) {
              System.out.println("ERROR: Password is null or empty");
              return false;
          }
  
          System.out.println("Authenticating user: " + username);
  
          // ダミーの認証処理
          for (int i = 0; i < 10; i++) {
              System.out.println("Authentication step " + i);
              if (i == 5) {
                  System.out.println("Validating credentials...");
              }
          }
  
          boolean isValid = username.length() > 3 && password.length() > 6;
  
          if (isValid) {
              validatedUsers.add(username);
              System.out.println("User " + username + " authenticated successfully");
          } else {
              System.out.println("Authentication failed for user: " + username);
          }
  
          return isValid;
      }
  
      /**
       * Session management
       */
      public String createSession(String username) {
          if (!validatedUsers.contains(username)) {
              System.out.println("ERROR: User not authenticated: " + username);
              return null;
          }
  
          String sessionId = "session_" + System.currentTimeMillis() + "_" + username;
          System.out.println("Creating session: " + sessionId);
  
          // Session creation process
          for (int i = 0; i < 15; i++) {
              System.out.println("Session creation step " + i);
              if (i == 7) {
                  System.out.println("Generating session token...");
              }
              if (i == 12) {
                  System.out.println("Storing session data...");
              }
          }
  
          System.out.println("Session created successfully: " + sessionId);
          return sessionId;
      }
  
      /**
       * Data validation
       */
      public boolean validateData(Map<String, Object> data) {
          if (data == null || data.isEmpty()) {
              System.out.println("ERROR: Data is null or empty");
              return false;
          }
  
          System.out.println("Validating data with " + data.size() + " fields");
  
          for (Map.Entry<String, Object> entry : data.entrySet()) {
              String key = entry.getKey();
              Object value = entry.getValue();
  
              System.out.println("Validating field: " + key);
  
              if (value == null) {
                  System.out.println("WARNING: Null value for field: " + key);
                  continue;
              }
  
              // Field-specific validation
              if (key.contains("email")) {
                  if (!validateEmail(value.toString())) {
                      System.out.println("ERROR: Invalid email format: " + value);
                      return false;
                  }
              } else if (key.contains("phone")) {
                  if (!validatePhoneNumber(value.toString())) {
                      System.out.println("ERROR: Invalid phone number: " + value);
                      return false;
                  }
              } else if (key.contains("date")) {
                  if (!validateDate(value.toString())) {
                      System.out.println("ERROR: Invalid date format: " + value);
                      return false;
                  }
              }
  
              System.out.println("Field " + key + " validation passed");
          }
  
          System.out.println("Data validation completed successfully");
          return true;
      }
  
      /**
       * Email format validation
       */
      private boolean validateEmail(String email) {
          System.out.println("Validating email: " + email);
          return email != null && email.contains("@") && email.contains(".");
      }
  
      /**
       * Phone number validation
       */
      private boolean validatePhoneNumber(String phone) {
          System.out.println("Validating phone number: " + phone);
          return phone != null && phone.matches("\\d{10,15}");
      }
  
      /**
       * Date format validation
       */
      private boolean validateDate(String date) {
          System.out.println("Validating date: " + date);
          try {
              LocalDateTime.parse(date, DateTimeFormatter.ofPattern(DATE_FORMAT));
              return true;
          } catch (Exception e) {
              return false;
          }
      }
  
      /**
       * Log operation
       */
      public void logOperation(String operation, String details) {
          String timestamp = LocalDateTime.now().format(DateTimeFormatter.ofPattern(DATE_FORMAT));
          String logEntry = String.format("[%s] %s: %s", timestamp, operation, details);
  
          System.out.println("LOG: " + logEntry);
  
          // Log file writing process (dummy)
          for (int i = 0; i < 5; i++) {
              System.out.println("Writing log entry, step " + i);
          }
      }
  
      /**
       * Cache management
       */
      public void manageCache(String key, Object value) {
          System.out.println("Managing cache for key: " + key);
  
          if (configurationCache.size() > 1000) {
              System.out.println("Cache size limit reached, cleaning up...");
              cleanupCache();
          }
  
          configurationCache.put(key, value);
          System.out.println("Cache updated for key: " + key);
  
          // Update cache statistics
          updateCacheStatistics();
      }
  
      /**
       * Cache cleanup
       */
      private void cleanupCache() {
          System.out.println("Starting cache cleanup...");
  
          int originalSize = configurationCache.size();
          Iterator<Map.Entry<String, Object>> iterator = configurationCache.entrySet().iterator();
  
          while (iterator.hasNext() && configurationCache.size() > 500) {
              iterator.next();
              iterator.remove();
          }
  
          int cleanedItems = originalSize - configurationCache.size();
          System.out.println("Cache cleanup completed. Removed " + cleanedItems + " items.");
      }
  
      /**
       * Update cache statistics
       */
      private void updateCacheStatistics() {
          System.out.println("Updating cache statistics...");
          System.out.println("Current cache size: " + configurationCache.size());
          System.out.println("Cache hit ratio: " + calculateCacheHitRatio());
      }
  
      /**
       * Calculate cache hit ratio
       */
      private double calculateCacheHitRatio() {
          // Dummy calculation
          return Math.random() * 0.3 + 0.7; // 70-100% range
      }
  
      /**
       * Backup processing
       */
      public void performBackup(String backupType) {
          System.out.println("Starting backup process: " + backupType);
  
          switch (backupType.toLowerCase()) {
              case "full":
                  performFullBackup();
                  break;
              case "incremental":
                  performIncrementalBackup();
                  break;
              case "differential":
                  performDifferentialBackup();
                  break;
              default:
                  System.out.println("Unknown backup type: " + backupType);
                  return;
          }
  
          System.out.println("Backup process completed: " + backupType);
      }
  
      /**
       * Full backup
       */
      private void performFullBackup() {
          System.out.println("Performing full backup...");
  
          for (int i = 0; i < 30; i++) {
              System.out.println("Full backup progress: " + (i + 1) + "/30");
  
              if (i == 10) {
                  System.out.println("Backing up database...");
              } else if (i == 20) {
                  System.out.println("Backing up configuration files...");
              } else if (i == 25) {
                  System.out.println("Backing up user data...");
              }
  
              try {
                  Thread.sleep(50);
              } catch (InterruptedException e) {
                  System.out.println("Backup interrupted");
                  return;
              }
          }
  
          System.out.println("Full backup completed successfully");
      }
  
      /**
       * Incremental backup
       */
      private void performIncrementalBackup() {
          System.out.println("Performing incremental backup...");
  
          for (int i = 0; i < 15; i++) {
              System.out.println("Incremental backup progress: " + (i + 1) + "/15");
  
              if (i == 5) {
                  System.out.println("Identifying changed files...");
              } else if (i == 10) {
                  System.out.println("Copying modified data...");
              }
          }
  
          System.out.println("Incremental backup completed successfully");
      }
  
      /**
       * Differential backup
       */
      private void performDifferentialBackup() {
          System.out.println("Performing differential backup...");
  
          for (int i = 0; i < 20; i++) {
              System.out.println("Differential backup progress: " + (i + 1) + "/20");
  
              if (i == 7) {
                  System.out.println("Comparing with last full backup...");
              } else if (i == 15) {
                  System.out.println("Copying differential data...");
              }
          }
  
          System.out.println("Differential backup completed successfully");
      }
  
      /**
       * レポート生成
       */
      public void generateReport(String reportType, Map<String, Object> parameters) {
          System.out.println("Generating report: " + reportType);
  
          if (parameters == null) {
              parameters = new HashMap<>();
          }
  
          // レポート生成の前処理
          prepareReportData(reportType, parameters);
  
          // レポートの種類に応じた処理
          switch (reportType.toLowerCase()) {
              case "sales":
                  generateSalesReport(parameters);
                  break;
              case "performance":
                  generatePerformanceReport(parameters);
                  break;
              case "user_activity":
                  generateUserActivityReport(parameters);
                  break;
              case "system_health":
                  generateSystemHealthReport(parameters);
                  break;
              default:
                  System.out.println("Unknown report type: " + reportType);
                  return;
          }
  
          // レポート生成の後処理
          finalizeReport(reportType);
  
          System.out.println("Report generation completed: " + reportType);
      }
  
      /**
       * レポートデータの準備
       */
      private void prepareReportData(String reportType, Map<String, Object> parameters) {
          System.out.println("Preparing report data for: " + reportType);
  
          for (int i = 0; i < 10; i++) {
              System.out.println("Data preparation step " + (i + 1) + "/10");
  
              if (i == 3) {
                  System.out.println("Loading data sources...");
              } else if (i == 7) {
                  System.out.println("Validating data integrity...");
              }
          }
  
          System.out.println("Report data preparation completed");
      }
  
      /**
       * 売上レポートの生成
       */
      private void generateSalesReport(Map<String, Object> parameters) {
          System.out.println("Generating sales report...");
  
          for (int i = 0; i < 25; i++) {
              System.out.println("Sales report generation step " + (i + 1) + "/25");
  
              if (i == 5) {
                  System.out.println("Calculating total sales...");
              } else if (i == 10) {
                  System.out.println("Analyzing sales trends...");
              } else if (i == 15) {
                  System.out.println("Generating charts and graphs...");
              } else if (i == 20) {
                  System.out.println("Formatting report layout...");
              }
          }
  
          System.out.println("Sales report generated successfully");
      }
  
      /**
       * パフォーマンスレポートの生成
       */
      private void generatePerformanceReport(Map<String, Object> parameters) {
          System.out.println("Generating performance report...");
  
          for (int i = 0; i < 20; i++) {
              System.out.println("Performance report generation step " + (i + 1) + "/20");
  
              if (i == 5) {
                  System.out.println("Collecting performance metrics...");
              } else if (i == 10) {
                  System.out.println("Analyzing system performance...");
              } else if (i == 15) {
                  System.out.println("Creating performance summary...");
              }
          }
  
          System.out.println("Performance report generated successfully");
      }
  
      /**
       * ユーザーアクティビティレポートの生成
       */
      private void generateUserActivityReport(Map<String, Object> parameters) {
          System.out.println("Generating user activity report...");
  
          for (int i = 0; i < 18; i++) {
              System.out.println("User activity report generation step " + (i + 1) + "/18");
  
              if (i == 6) {
                  System.out.println("Analyzing user behavior patterns...");
              } else if (i == 12) {
                  System.out.println("Calculating user engagement metrics...");
              }
          }
  
          System.out.println("User activity report generated successfully");
      }
  
      /**
       * システムヘルスレポートの生成
       */
      private void generateSystemHealthReport(Map<String, Object> parameters) {
          System.out.println("Generating system health report...");
  
          for (int i = 0; i < 22; i++) {
              System.out.println("System health report generation step " + (i + 1) + "/22");
  
              if (i == 5) {
                  System.out.println("Checking system resources...");
              } else if (i == 10) {
                  System.out.println("Analyzing error logs...");
              } else if (i == 15) {
                  System.out.println("Evaluating system stability...");
              }
          }
  
          System.out.println("System health report generated successfully");
      }
  
      /**
       * レポートの最終処理
       */
      private void finalizeReport(String reportType) {
          System.out.println("Finalizing report: " + reportType);
  
          for (int i = 0; i < 8; i++) {
              System.out.println("Report finalization step " + (i + 1) + "/8");
  
              if (i == 3) {
                  System.out.println("Applying report formatting...");
              } else if (i == 6) {
                  System.out.println("Saving report to file...");
              }
          }
  
          System.out.println("Report finalization completed");
      }
  
      /**
       * Updates customer name.
       * This method contains important business logic.
       * @param customerId Customer ID
       * @param newName New customer name
       */
      public void updateCustomerName(String customerId, String newName) {
          // Originally, complex processing such as database updates would be included here
          if (customerId == null || customerId.isEmpty()) {
              System.out.println("ERROR: Customer ID is null or empty.");
              return;
          }
          if (newName == null || newName.isEmpty()) {
              System.out.println("ERROR: New name is null or empty.");
              return;
          }
          System.out.println("Updating customer " + customerId + " to name " + newName);
          // ... About 50 lines of dummy processing ...
          for (int i = 0; i < 50; i++) {
              System.out.println("Processing step " + i);
          }
          System.out.println("Customer name updated successfully.");
      }
  
      /**
       * Get customer information
       */
      public Map<String, Object> getCustomerInfo(String customerId) {
          System.out.println("Retrieving customer information for ID: " + customerId);
  
          if (customerId == null || customerId.isEmpty()) {
              System.out.println("ERROR: Customer ID is null or empty");
              return null;
          }
  
          Map<String, Object> customerInfo = new HashMap<>();
  
          // Dummy customer information retrieval process
          for (int i = 0; i < 15; i++) {
              System.out.println("Customer info retrieval step " + (i + 1) + "/15");
  
              if (i == 5) {
                  System.out.println("Querying customer database...");
                  customerInfo.put("id", customerId);
                  customerInfo.put("name", "Customer_" + customerId);
              } else if (i == 10) {
                  System.out.println("Loading customer preferences...");
                  customerInfo.put("email", "customer" + customerId + "@example.com");
                  customerInfo.put("phone", "123-456-" + customerId);
              }
          }
  
          customerInfo.put("status", "active");
          customerInfo.put("created_date", LocalDateTime.now().toString());
  
          System.out.println("Customer information retrieved successfully");
          return customerInfo;
      }
  
      /**
       * Delete customer
       */
      public boolean deleteCustomer(String customerId) {
          System.out.println("Deleting customer: " + customerId);
  
          if (customerId == null || customerId.isEmpty()) {
              System.out.println("ERROR: Customer ID is null or empty");
              return false;
          }
  
          // Pre-deletion validation
          for (int i = 0; i < 10; i++) {
              System.out.println("Pre-deletion validation step " + (i + 1) + "/10");
  
              if (i == 3) {
                  System.out.println("Checking customer dependencies...");
              } else if (i == 7) {
                  System.out.println("Validating deletion permissions...");
              }
          }
  
          // Actual deletion process
          for (int i = 0; i < 20; i++) {
              System.out.println("Customer deletion step " + (i + 1) + "/20");
  
              if (i == 5) {
                  System.out.println("Removing customer data...");
              } else if (i == 10) {
                  System.out.println("Cleaning up related records...");
              } else if (i == 15) {
                  System.out.println("Updating audit logs...");
              }
          }
  
          System.out.println("Customer " + customerId + " deleted successfully");
          return true;
      }
  
      /**
       * Order processing
       */
      public String processOrder(String customerId, List<String> items, double totalAmount) {
          System.out.println("Processing order for customer: " + customerId);
  
          if (customerId == null || customerId.isEmpty()) {
              System.out.println("ERROR: Customer ID is required");
              return null;
          }
  
          if (items == null || items.isEmpty()) {
              System.out.println("ERROR: Order items are required");
              return null;
          }
  
          if (totalAmount <= 0) {
              System.out.println("ERROR: Invalid total amount: " + totalAmount);
              return null;
          }
  
          String orderId = "ORDER_" + System.currentTimeMillis();
          System.out.println("Generated order ID: " + orderId);
  
          // Order processing steps
          for (int i = 0; i < 25; i++) {
              System.out.println("Order processing step " + (i + 1) + "/25");
  
              if (i == 3) {
                  System.out.println("Validating customer account...");
              } else if (i == 7) {
                  System.out.println("Checking item availability...");
              } else if (i == 12) {
                  System.out.println("Processing payment...");
              } else if (i == 17) {
                  System.out.println("Updating inventory...");
              } else if (i == 22) {
                  System.out.println("Generating order confirmation...");
              }
          }
  
          System.out.println("Order processed successfully: " + orderId);
          return orderId;
      }
  
      /**
       * Inventory management
       */
      public void manageInventory(String action, String itemId, int quantity) {
          System.out.println("Managing inventory - Action: " + action + ", Item: " + itemId + ", Quantity: " + quantity);
  
          if (action == null || action.isEmpty()) {
              System.out.println("ERROR: Action is required");
              return;
          }
  
          if (itemId == null || itemId.isEmpty()) {
              System.out.println("ERROR: Item ID is required");
              return;
          }
  
          switch (action.toLowerCase()) {
              case "add":
                  addInventory(itemId, quantity);
                  break;
              case "remove":
                  removeInventory(itemId, quantity);
                  break;
              case "update":
                  updateInventory(itemId, quantity);
                  break;
              case "check":
                  checkInventory(itemId);
                  break;
              default:
                  System.out.println("ERROR: Unknown inventory action: " + action);
                  return;
          }
  
          System.out.println("Inventory management completed for item: " + itemId);
      }
  
      /**
       * Add inventory
       */
      private void addInventory(String itemId, int quantity) {
          System.out.println("Adding inventory for item: " + itemId + ", quantity: " + quantity);
  
          for (int i = 0; i < 12; i++) {
              System.out.println("Inventory addition step " + (i + 1) + "/12");
  
              if (i == 4) {
                  System.out.println("Validating item information...");
              } else if (i == 8) {
                  System.out.println("Updating inventory database...");
              }
          }
  
          System.out.println("Inventory added successfully");
      }
  
      /**
       * Remove inventory
       */
      private void removeInventory(String itemId, int quantity) {
          System.out.println("Removing inventory for item: " + itemId + ", quantity: " + quantity);
  
          for (int i = 0; i < 10; i++) {
              System.out.println("Inventory removal step " + (i + 1) + "/10");
  
              if (i == 3) {
                  System.out.println("Checking available quantity...");
              } else if (i == 7) {
                  System.out.println("Updating inventory records...");
              }
          }
  
          System.out.println("Inventory removed successfully");
      }
  
      /**
       * Update inventory
       */
      private void updateInventory(String itemId, int quantity) {
          System.out.println("Updating inventory for item: " + itemId + ", new quantity: " + quantity);
  
          for (int i = 0; i < 8; i++) {
              System.out.println("Inventory update step " + (i + 1) + "/8");
  
              if (i == 3) {
                  System.out.println("Calculating inventory changes...");
              } else if (i == 6) {
                  System.out.println("Applying inventory updates...");
              }
          }
  
          System.out.println("Inventory updated successfully");
      }
  
      /**
       * Check inventory
       */
      private void checkInventory(String itemId) {
          System.out.println("Checking inventory for item: " + itemId);
  
          for (int i = 0; i < 6; i++) {
              System.out.println("Inventory check step " + (i + 1) + "/6");
  
              if (i == 2) {
                  System.out.println("Querying inventory database...");
              } else if (i == 4) {
                  System.out.println("Calculating available quantity...");
              }
          }
  
          int availableQuantity = (int) (Math.random() * 100) + 1;
          System.out.println("Available quantity for item " + itemId + ": " + availableQuantity);
      }
  
      /**
       * Send notification
       */
      public void sendNotification(String recipient, String message, String type) {
          System.out.println("Sending notification to: " + recipient);
          System.out.println("Message: " + message);
          System.out.println("Type: " + type);
  
          if (recipient == null || recipient.isEmpty()) {
              System.out.println("ERROR: Recipient is required");
              return;
          }
  
          if (message == null || message.isEmpty()) {
              System.out.println("ERROR: Message is required");
              return;
          }
  
          // Notification sending process
          for (int i = 0; i < 15; i++) {
              System.out.println("Notification sending step " + (i + 1) + "/15");
  
              if (i == 3) {
                  System.out.println("Validating recipient address...");
              } else if (i == 7) {
                  System.out.println("Formatting notification message...");
              } else if (i == 11) {
                  System.out.println("Delivering notification...");
              }
          }
  
          System.out.println("Notification sent successfully to: " + recipient);
      }
  
      /**
       * System shutdown
       */
      public void shutdownSystem() {
          System.out.println("Initiating system shutdown...");
  
          // Pre-shutdown processing
          for (int i = 0; i < 20; i++) {
              System.out.println("Shutdown preparation step " + (i + 1) + "/20");
  
              if (i == 3) {
                  System.out.println("Saving pending operations...");
                  savePendingOperations();
              } else if (i == 8) {
                  System.out.println("Closing database connections...");
                  closeDatabaseConnections();
              } else if (i == 13) {
                  System.out.println("Clearing cache...");
                  configurationCache.clear();
              } else if (i == 17) {
                  System.out.println("Finalizing logs...");
                  finalizeSystemLogs();
              }
          }
  
          System.out.println("System shutdown completed successfully");
      }
  
      /**
       * Save pending operations
       */
      private void savePendingOperations() {
          System.out.println("Saving " + pendingOperations.size() + " pending operations...");
  
          while (!pendingOperations.isEmpty()) {
              String operation = pendingOperations.poll();
              System.out.println("Saving operation: " + operation);
          }
  
          System.out.println("All pending operations saved");
      }
  
      /**
       * Close database connections
       */
      private void closeDatabaseConnections() {
          System.out.println("Closing database connections...");
  
          for (String connection : activeConnections) {
              System.out.println("Closing connection: " + connection);
          }
  
          activeConnections.clear();
          System.out.println("All database connections closed");
      }
  
      /**
       * Finalize system logs
       */
      private void finalizeSystemLogs() {
          System.out.println("Finalizing system logs...");
  
          for (int i = 0; i < 5; i++) {
              System.out.println("Log finalization step " + (i + 1) + "/5");
          }
  
          System.out.println("System logs finalized");
      }
  
      /**
       * Error handling
       */
      public void handleError(Exception error, String context) {
          System.out.println("Handling error in context: " + context);
          System.out.println("Error message: " + error.getMessage());
  
          // Record error log
          logOperation("ERROR", "Error in " + context + ": " + error.getMessage());
  
          // Processing according to error type
          if (error instanceof SQLException) {
              handleDatabaseError((SQLException) error);
          } else if (error instanceof IllegalArgumentException) {
              handleValidationError((IllegalArgumentException) error);
          } else if (error instanceof RuntimeException) {
              handleRuntimeError((RuntimeException) error);
          } else {
              handleGenericError(error);
          }
  
          System.out.println("Error handling completed for context: " + context);
      }
  
      /**
       * Handle database error
       */
      private void handleDatabaseError(SQLException error) {
          System.out.println("Handling database error: " + error.getSQLState());
  
          for (int i = 0; i < 8; i++) {
              System.out.println("Database error handling step " + (i + 1) + "/8");
  
              if (i == 3) {
                  System.out.println("Attempting database reconnection...");
              } else if (i == 6) {
                  System.out.println("Rolling back transaction...");
              }
          }
  
          System.out.println("Database error handled");
      }
  
      /**
       * Handle validation error
       */
      private void handleValidationError(IllegalArgumentException error) {
          System.out.println("Handling validation error: " + error.getMessage());
  
          for (int i = 0; i < 5; i++) {
              System.out.println("Validation error handling step " + (i + 1) + "/5");
          }
  
          System.out.println("Validation error handled");
      }
  
      /**
       * Handle runtime error
       */
      private void handleRuntimeError(RuntimeException error) {
          System.out.println("Handling runtime error: " + error.getMessage());
  
          for (int i = 0; i < 10; i++) {
              System.out.println("Runtime error handling step " + (i + 1) + "/10");
  
              if (i == 4) {
                  System.out.println("Collecting error context...");
              } else if (i == 7) {
                  System.out.println("Notifying administrators...");
              }
          }
  
          System.out.println("Runtime error handled");
      }
  
      /**
       * Handle generic error
       */
      private void handleGenericError(Exception error) {
          System.out.println("Handling generic error: " + error.getClass().getSimpleName());
  
          for (int i = 0; i < 6; i++) {
              System.out.println("Generic error handling step " + (i + 1) + "/6");
          }
  
          System.out.println("Generic error handled");
      }
  
      /**
       * Performance monitoring
       */
      public void monitorPerformance() {
          System.out.println("Starting performance monitoring...");
  
          long startTime = System.currentTimeMillis();
  
          // Monitor CPU usage
          monitorCpuUsage();
  
          // Monitor memory usage
          monitorMemoryUsage();
  
          // Monitor disk I/O
          monitorDiskIO();
  
          // Monitor network usage
          monitorNetworkUsage();
  
          long endTime = System.currentTimeMillis();
          long duration = endTime - startTime;
  
          System.out.println("Performance monitoring completed in " + duration + "ms");
      }
  
      /**
       * Monitor CPU usage
       */
      private void monitorCpuUsage() {
          System.out.println("Monitoring CPU usage...");
  
          for (int i = 0; i < 10; i++) {
              System.out.println("CPU monitoring step " + (i + 1) + "/10");
              double cpuUsage = Math.random() * 100;
              System.out.println("Current CPU usage: " + String.format("%.2f", cpuUsage) + "%");
  
              if (cpuUsage > 80) {
                  System.out.println("WARNING: High CPU usage detected!");
              }
          }
  
          System.out.println("CPU monitoring completed");
      }
  
      /**
       * Monitor memory usage
       */
      private void monitorMemoryUsage() {
          System.out.println("Monitoring memory usage...");
  
          Runtime runtime = Runtime.getRuntime();
  
          for (int i = 0; i < 8; i++) {
              System.out.println("Memory monitoring step " + (i + 1) + "/8");
  
              long totalMemory = runtime.totalMemory();
              long freeMemory = runtime.freeMemory();
              long usedMemory = totalMemory - freeMemory;
              double usagePercentage = (double) usedMemory / totalMemory * 100;
  
              System.out.println("Memory usage: " + String.format("%.2f", usagePercentage) + "%");
  
              if (usagePercentage > 85) {
                  System.out.println("WARNING: High memory usage detected!");
              }
          }
  
          System.out.println("Memory monitoring completed");
      }
  
      /**
       * Monitor disk I/O
       */
      private void monitorDiskIO() {
          System.out.println("Monitoring disk I/O...");
  
          for (int i = 0; i < 6; i++) {
              System.out.println("Disk I/O monitoring step " + (i + 1) + "/6");
  
              double readRate = Math.random() * 100;
              double writeRate = Math.random() * 100;
  
              System.out.println("Disk read rate: " + String.format("%.2f", readRate) + " MB/s");
              System.out.println("Disk write rate: " + String.format("%.2f", writeRate) + " MB/s");
          }
  
          System.out.println("Disk I/O monitoring completed");
      }
  
      /**
       * Monitor network usage
       */
      private void monitorNetworkUsage() {
          System.out.println("Monitoring network usage...");
  
          for (int i = 0; i < 7; i++) {
              System.out.println("Network monitoring step " + (i + 1) + "/7");
  
              double inboundTraffic = Math.random() * 1000;
              double outboundTraffic = Math.random() * 1000;
  
              System.out.println("Inbound traffic: " + String.format("%.2f", inboundTraffic) + " KB/s");
              System.out.println("Outbound traffic: " + String.format("%.2f", outboundTraffic) + " KB/s");
          }
  
          System.out.println("Network monitoring completed");
      }
  
      /**
       * Security check
       */
      public void performSecurityCheck() {
          System.out.println("Starting security check...");
  
          // Check access permissions
          checkAccessPermissions();
  
          // Validate security settings
          validateSecuritySettings();
  
          // Perform vulnerability scan
          performVulnerabilityScan();
  
          // Review security logs
          reviewSecurityLogs();
  
          System.out.println("Security check completed");
      }
  
      /**
       * Check access permissions
       */
      private void checkAccessPermissions() {
          System.out.println("Checking access permissions...");
  
          for (int i = 0; i < 12; i++) {
              System.out.println("Permission check step " + (i + 1) + "/12");
  
              if (i == 3) {
                  System.out.println("Validating user permissions...");
              } else if (i == 7) {
                  System.out.println("Checking file system permissions...");
              } else if (i == 10) {
                  System.out.println("Verifying database access rights...");
              }
          }
  
          System.out.println("Access permissions check completed");
      }
  
      /**
       * Validate security settings
       */
      private void validateSecuritySettings() {
          System.out.println("Validating security settings...");
  
          for (int i = 0; i < 9; i++) {
              System.out.println("Security settings validation step " + (i + 1) + "/9");
  
              if (i == 3) {
                  System.out.println("Checking encryption settings...");
              } else if (i == 6) {
                  System.out.println("Validating authentication configuration...");
              }
          }
  
          System.out.println("Security settings validation completed");
      }
  
      /**
       * Perform vulnerability scan
       */
      private void performVulnerabilityScan() {
          System.out.println("Performing vulnerability scan...");
  
          for (int i = 0; i < 15; i++) {
              System.out.println("Vulnerability scan step " + (i + 1) + "/15");
  
              if (i == 5) {
                  System.out.println("Scanning for known vulnerabilities...");
              } else if (i == 10) {
                  System.out.println("Checking for security patches...");
              }
          }
  
          System.out.println("Vulnerability scan completed");
      }
  
      /**
       * Review security logs
       */
      private void reviewSecurityLogs() {
          System.out.println("Reviewing security logs...");
  
          for (int i = 0; i < 8; i++) {
              System.out.println("Security log review step " + (i + 1) + "/8");
  
              if (i == 3) {
                  System.out.println("Analyzing failed login attempts...");
              } else if (i == 6) {
                  System.out.println("Checking for suspicious activities...");
              }
          }
  
          System.out.println("Security log review completed");
      }
  
      /**
       * Data synchronization
       */
      public void synchronizeData(String sourceSystem, String targetSystem) {
          System.out.println("Starting data synchronization from " + sourceSystem + " to " + targetSystem);
  
          if (sourceSystem == null || sourceSystem.isEmpty()) {
              System.out.println("ERROR: Source system is required");
              return;
          }
  
          if (targetSystem == null || targetSystem.isEmpty()) {
              System.out.println("ERROR: Target system is required");
              return;
          }
  
          // Prepare data synchronization
          prepareSynchronization(sourceSystem, targetSystem);
  
          // Extract data
          extractData(sourceSystem);
  
          // Transform data
          transformData();
  
          // Load data
          loadData(targetSystem);
  
          // Verify synchronization
          verifySynchronization(sourceSystem, targetSystem);
  
          System.out.println("Data synchronization completed successfully");
      }
  
      /**
       * Prepare synchronization
       */
      private void prepareSynchronization(String sourceSystem, String targetSystem) {
          System.out.println("Preparing synchronization between " + sourceSystem + " and " + targetSystem);
  
          for (int i = 0; i < 10; i++) {
              System.out.println("Synchronization preparation step " + (i + 1) + "/10");
  
              if (i == 3) {
                  System.out.println("Establishing connections...");
              } else if (i == 7) {
                  System.out.println("Validating data schemas...");
              }
          }
  
          System.out.println("Synchronization preparation completed");
      }
  
      /**
       * Extract data
       */
      private void extractData(String sourceSystem) {
          System.out.println("Extracting data from " + sourceSystem);
  
          for (int i = 0; i < 20; i++) {
              System.out.println("Data extraction step " + (i + 1) + "/20");
  
              if (i == 5) {
                  System.out.println("Querying source database...");
              } else if (i == 10) {
                  System.out.println("Processing data records...");
              } else if (i == 15) {
                  System.out.println("Validating extracted data...");
              }
          }
  
          System.out.println("Data extraction completed");
      }
  
      /**
       * Transform data
       */
      private void transformData() {
          System.out.println("Transforming data...");
  
          for (int i = 0; i < 15; i++) {
              System.out.println("Data transformation step " + (i + 1) + "/15");
  
              if (i == 5) {
                  System.out.println("Applying data mapping rules...");
              } else if (i == 10) {
                  System.out.println("Performing data cleansing...");
              }
          }
  
          System.out.println("Data transformation completed");
      }
  
      /**
       * Load data
       */
      private void loadData(String targetSystem) {
          System.out.println("Loading data into " + targetSystem);
  
          for (int i = 0; i < 18; i++) {
              System.out.println("Data loading step " + (i + 1) + "/18");
  
              if (i == 6) {
                  System.out.println("Inserting new records...");
              } else if (i == 12) {
                  System.out.println("Updating existing records...");
              }
          }
  
          System.out.println("Data loading completed");
      }
  
      /**
       * Verify synchronization
       */
      private void verifySynchronization(String sourceSystem, String targetSystem) {
          System.out.println("Verifying synchronization between " + sourceSystem + " and " + targetSystem);
  
          for (int i = 0; i < 12; i++) {
              System.out.println("Synchronization verification step " + (i + 1) + "/12");
  
              if (i == 4) {
                  System.out.println("Comparing record counts...");
              } else if (i == 8) {
                  System.out.println("Validating data integrity...");
              }
          }
  
          System.out.println("Synchronization verification completed");
      }
  
      /**
       * Main method - for testing
       */
      public static void main(String[] args) {
          System.out.println("BigService Demo Application");
          System.out.println("==========================");
  
          BigService service = new BigService();
  
          // Test basic functions
          System.out.println("\n--- Testing Basic Functions ---");
          service.authenticateUser("testuser", "password123");
          service.createSession("testuser");
  
          // Test customer management
          System.out.println("\n--- Testing Customer Management ---");
          service.updateCustomerName("CUST001", "New Customer Name");
          Map<String, Object> customerInfo = service.getCustomerInfo("CUST001");
  
          // Test report generation
          System.out.println("\n--- Testing Report Generation ---");
          Map<String, Object> reportParams = new HashMap<>();
          reportParams.put("start_date", "2024-01-01");
          reportParams.put("end_date", "2024-12-31");
          service.generateReport("sales", reportParams);
  
          // Test performance monitoring
          System.out.println("\n--- Testing Performance Monitoring ---");
          service.monitorPerformance();
  
          // Test security check
          System.out.println("\n--- Testing Security Check ---");
          service.performSecurityCheck();
  
          System.out.println("\n--- Demo Completed ---");
          System.out.println("BigService demo application finished successfully.");
      }
  }
  