使用接口编写流畅风格的API时避免代码重复

public class FluentApiExample {
    private String name;
    private int age;

    public FluentApiExample setName(String name) {
        this.name = name;
        return this;
    }

    public FluentApiExample setAge(int age) {
        this.age = age;
        return this;
    }

    public void printInfo() {
        System.out.println("Name: " + name + ", Age: " + age);
    }

    // 提取公共方法
    private FluentApiExample validate() {
        if (name == null || name.isEmpty()) {
            throw new IllegalArgumentException("Name cannot be null or empty");
        }
        if (age < 0) {
            throw new IllegalArgumentException("Age cannot be negative");
        }
        return this;
    }

    public FluentApiExample createAndPrint(String name, int age) {
        return setName(name)
                .setAge(age)
                .validate()
                .printInfo();
    }

    public static void main(String[] args) {
        FluentApiExample example = new FluentApiExample();
        example.createAndPrint("Alice", 30);
    }
}