Decorator Pattern for Capital Letters

Design Pattern: Decorator Pattern

The Decorator Pattern allows us to dynamically add new functionality to an object without modifying its structure. In the context of creating capital letters for a column of data, we can use the Decorator Pattern to enhance the existing functionality of the column and convert the data to capital letters.

Implementation Steps:

1. Create an interface or abstract class that defines the base behavior for the column.
2. Implement a concrete class that represents the original behavior of the column.
3. Create a decorator class that extends the base class/interface and wraps an instance of the base class.
4. Add a new behavior to the decorator class that converts the data to capital letters.
5. Use the decorator class to enhance the behavior of the original column.

Here's an example implementation in Python:

# Step 1: Define the base behavior for the column
class DataColumn:
    def __init__(self, data):
        self.data = data
    
    def get_data(self):
        return self.data

# Step 2: Implement the original behavior of the column
class OriginalColumn(DataColumn):
    def __init__(self, data):
        super().__init__(data)

# Step 3: Create the decorator class
class CapitalLettersColumn(DataColumn):
    def __init__(self, original):
        self.original = original
    
    # Step 4: Add new behavior to the decorator class
    def get_data(self):
        data = self.original.get_data()
        return data.upper()

# Step 5: Use the decorator class to enhance the behavior of the original column
data_column = OriginalColumn("example data")
decorated_column = CapitalLettersColumn(data_column)
capital_data = decorated_column.get_data() # Returns "EXAMPLE DATA"

In this implementation, the DataColumn is the base behavior for the column, the OriginalColumn is the concrete class that represents the original behavior, and the CapitalLettersColumn is the decorator class that adds the new behavior of converting the data to capital letters. We create an instance of OriginalColumn and then wrap it with an instance of CapitalLettersColumn to enhance its behavior.

By following the Decorator Pattern, we can easily add new functionality to the column without modifying its original implementation. This makes the code more flexible and maintainable.