Java Template Method

The Template Method Pattern is a behavioral design pattern that defines the skeleton of an algorithm in a method, deferring some steps to subclasses. Template Method lets subclasses redefine certain steps of an algorithm without changing the algorithm's structure.

定义抽象类

java

        public abstract class AbstractClass {
    // 模板方法，定义了算法的骨架
    public final void templateMethod() {
        primitiveOperation1();
        primitiveOperation2();
        concreteOperation();
    }

    // 基本操作（由子类实现）
    protected abstract void primitiveOperation1();
    protected abstract void primitiveOperation2();

    // 具体操作（可以由父类实现，也可以由子类重写）
    private void concreteOperation() {
        System.out.println("Concrete operation in AbstractClass");
    }
}

子类实现基本操作

java

        public class ConcreteClass extends AbstractClass {
    @Override
    protected void primitiveOperation1() {
        System.out.println("Primitive Operation 1 in ConcreteClass");
    }

    @Override
    protected void primitiveOperation2() {
        System.out.println("Primitive Operation 2 in ConcreteClass");
    }
}

使用模板方法模式

java

        public class TemplateMethodPatternDemo {
    public static void main(String[] args) {
        AbstractClass abstractClass = new ConcreteClass();
        abstractClass.templateMethod();
    }
}