聊技术

java编程思想

5.8.1 可变参数列表
import org.junit.Test;
public class JavaDemo {

    @Test
    public void main() {
        print(1, "one", "two");
        print(0);
    }

    public void print(int required, String... trailing) {
        System.out.println("required = " + required);
        for (String s : trailing) {
            System.out.println("s = " + s);
        }
    }
}
枚举：
import org.junit.Test;

public class JavaDemo {

    @Test
    public void main() {
        Spiciness medium = Spiciness.MEDIUM;
        System.out.println("medium = " + medium);
        for (Spiciness s : Spiciness.values()) {
            System.out.println("s = " + s);
            System.out.println("s = " + s.ordinal());
        }
    }

    public enum Spiciness {
        NOT, MILD, MEDIUM, HOT, FLAMING
    }
}
结果：
medium = MEDIUM
s = NOT
s = 0
s = MILD
s = 1
s = MEDIUM
s = 2
s = HOT
s = 3
s = FLAMING
s = 4

6.2.4 protected：继承访问权限
相同包内的其他类可以访问protected

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