What is the purpose of using the template method in programming?

The Template Method is a behavioral design pattern that defines the skeleton of an algorithm in a base class method, leaving some steps to be implemented by subclasses. The goal is to ensure a fixed order of operations, allowing subclasses to modify details without changing the algorithm's structure.

Example: The base class describes a method templateMethod(), which calls several abstract or overridden methods. Subclasses implement these methods in their own way.

abstract class DataProcessor {
    // Template method
    public final void process() {
        readData();
        processData();
        saveData();
    }
    abstract void readData();
    abstract void processData();
    abstract void saveData();
}

class CSVDataProcessor extends DataProcessor {
    void readData() { System.out.println("Reading CSV"); }
    void processData() { System.out.println("Processing CSV"); }
    void saveData() { System.out.println("Saving CSV"); }
}

This approach increases code reuse and simplifies maintenance.