记录工作中遇到的一些后续需要学习的点

java

Optional

(对象非空检验)
https://www.cnblogs.com/zhangboyu/p/7580262.html

Function

Java8的方法引用

(stream 语法糖 lamda)

https://www.jianshu.com/p/62465b26818f

java函数式编程之Consumer

https://blog.csdn.net/chuji2012/article/details/77871011

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

public Student(String name, int age) {
    this.name = name;
    this.age = age;
}

public String getName() {
    return name;
}

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

public int getAge() {
    return age;
}

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

public static void main(String[] args) {
    Student stu = new Student("zhangsan",13);
    Consumer<Student> consumer = student -> {
        student.setAge(19);
        student.setName("wangwu");
    };
    consumer.accept(stu);
    System.out.println(stu.getAge());
}

}

ProcessBuilder

(执行linux进程)

https://blog.csdn.net/monkey_win/article/details/103303174

https://blog.csdn.net/qq_44952664/article/details/89736535

enum枚举

public enum DatabaseType {

MYSQL(0,"MySql"),
ORACLE(1,"Oracle");

DatabaseType(int code, String desc) {
    this.code = code;
    this.desc = desc;
}

private int code;
private String desc;

public int getCode() {
    return code;
}

public String getDesc() {
    return desc;
}

}

RunTime.getRunTime().addShutdownHook用法

https://blog.csdn.net/wgw335363240/article/details/5854402

这个方法的意思就是在jvm中增加一个关闭的钩子，当jvm关闭的时候，会执行系统中已经设置的所有通过方法addShutdownHook添加的钩子，当系统执行完这些钩子后，jvm才会关闭。所以这些钩子可以在jvm关闭的时候进行内存清理、对象销毁等操作。

assert

(断言) 现在用unit代替了

---

jvm

JNI

CodeCache（也是涉及到JNI）

---

数据结构

Treeset 就是用红黑树作为索引结构的