Exception handling is an important aspect of developing robust and error-free Java applications. While Java provides a wide range of built-in exception classes, sometimes it’s necessary to handle exceptions that don’t fall under those predefined categories. That’s where wrapper classes come in handy.

Wrapper classes in Java allow us to wrap an exception in a custom class, providing additional information and context to further enhance the exception handling process. This can be particularly helpful when dealing with complex codebases or when we need to handle specific types of exceptions that aren’t covered by the standard Java exceptions.

Here’s an example of how we can leverage wrapper classes for exception handling in Java:

public class DatabaseException extends RuntimeException {
    private int errorCode;

    public DatabaseException(String message, int errorCode) {
        super(message);
        this.errorCode = errorCode;
    }

    public int getErrorCode() {
        return errorCode;
    }
}

// Usage example
public class DatabaseService {
    public void connectToDatabase() {
        try {
            // Code to connect to the database
        } catch (SQLException e) {
            int errorCode = e.getErrorCode();
            throw new DatabaseException("Error connecting to the database", errorCode);
        }
    }
}

public class Application {
    public static void main(String[] args) {
        DatabaseService databaseService = new DatabaseService();
        try {
            databaseService.connectToDatabase();
        } catch (DatabaseException e) {
            // Handle the wrapped database exception
            int errorCode = e.getErrorCode();
            System.out.println("Database connection failed with error code: " + errorCode);
        }
    }
}

In this example, we have created a custom exception class called DatabaseException that extends the RuntimeException class. The DatabaseException class has an additional errorCode field that allows us to store information about the specific error that occurred.

Inside the connectToDatabase method of the DatabaseService class, we catch the SQLException thrown when connecting to the database. Instead of rethrowing the SQLException, we wrap it in our custom DatabaseException and pass the relevant error code.

In the main method of the Application class, we handle the wrapped DatabaseException and extract the error code to provide feedback to the user.

Using wrapper classes for exception handling allows us to add more context and information to the exceptions, making it easier to handle and debug errors in our Java applications.

#java #exceptionhandling