MVC

<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-webmvc</artifactId>
    <version>6.0.10</version>
</dependency>

Controller

页面

@Controller   //直接添加注解即可
public class HelloController {

    @RequestMapping("/index")   //直接填写访问路径
    public ModelAndView index(){
        ModelAndView modelAndView = new ModelAndView("index");
        modelAndView.getModel().put("arg", "value");   //将name传递给Model
        return modelAndView;
          //返回后会经过视图解析器进行处理
    }

    @RequestMapping(value = "/index")
    public String index(Model model){  //这里不仅仅可以是Model，还可以是Map、ModelMap
        model.addAttribute("arg", "value");
        return "index";
    }
}

重定向

@RequestMapping("/index")
public String index(){
    return "redirect:page";
}

请求转发

@RequestMapping("/index")
public String index(){
    return "forward:home";
}

Bean的Web作用域

Bean的作用域：

1. Singleton
2. Prototype
3. Request HTTP请求产生新实例，结束后Bean消失
4. Session 每一个会话
5. Global Session

RESTFul

一种设计风格。RESTful风格的设计允许将参数通过URL拼接传到服务端。

http://localhost:8080/mvc/index/13579

@RequestMapping("/index/{str}")
public String index(@PathVariable String str) {
    System.out.println(str);
    return "index";
}

文件上传

public class MainInitializer extends AbstractAnnotationConfigDispatcherServletInitializer {

    ...

    @Override
    protected void customizeRegistration(ServletRegistration.Dynamic registration) {
          // 直接通过registration配置Multipart相关配置，必须配置临时上传路径，建议选择方便打开的
        // 同样可以设置其他属性：maxFileSize, maxRequestSize, fileSizeThreshold
        registration.setMultipartConfig(new MultipartConfigElement("/path/to/save"));
    }
}

Controller模板

@RequestMapping(value = "/upload", method = RequestMethod.POST)
@ResponseBody
public String upload(@RequestParam MultipartFile file) throws IOException {
    File fileObj = new File("filename.png");
    file.transferTo(fileObj);
    System.out.println("用户上传的文件已保存到："+fileObj.getAbsolutePath());
    return "文件上传成功！";
}

前端模板

<div>
    <form action="upload" method="post" enctype="multipart/form-data">
        <input type="file" name="file">
        <input type="submit">
    </form>
</div>

application.properties

Property形式

server.port=80 // 端口号
aruge.arugement=value

@Value("{argue.argument}")
String argu;

YAML形式

server:
    port: 80

spring:
    datasource:
        url: jdbc:mysql://localhost:3306/db_name
        username:
        password:
        driver-class-name: com.mysql.cj.Driver
    mvc:
        static-path-pattern: /static/**
    security:
        filter:
            order: -100 # Spring Security Filter 优先级
        user:
            name: 'admin'
            password: 'Abc123.'
            roles:
                - admin
                - user

所有的Java云平台都能够使用基于JAR的打包方式，WAR文件只在一些云平台上能够运行。

Pom.xml 更换 Maven 源

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>org.springframework.quoters</groupId>
    <artifactId>quoters-incorporated</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>quoters-incorporated</name>
    <description>REST service to support the guides</description>

    <developers>
        <developer>
            <id>gturnquist</id>
            <name>Greg Turnquist</name>
            <email>gturnquist at vmware.com</email>
            <organization>VMware, Inc.</organization>
            <roles>
                <role>Project Lead</role>
            </roles>
        </developer>
    </developers>

    <organization>
        <name>VMware, Inc.</name>
        <url>https://spring.io</url>
    </organization>

    <licenses>
        <license>
            <name>Apache License, Version 2.0</name>
            <url>https://www.apache.org/licenses/LICENSE-2.0</url>
            <comments>
                Copyright 2011 the original author or authors.

                Licensed under the Apache License, Version 2.0 (the "License");
                you may not use this file except in compliance with the License.
                You may obtain a copy of the License at

                https://www.apache.org/licenses/LICENSE-2.0

                Unless required by applicable law or agreed to in writing, software
                distributed under the License is distributed on an "AS IS" BASIS,
                WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
                implied.
                See the License for the specific language governing permissions and
                limitations under the License.
            </comments>
        </license>
    </licenses>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.7.5</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>com.h2database</groupId>
            <artifactId>h2</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <!-- 配置阿里云仓库 -->
<repositories>
        <repository>
            <id>aliyun-repos</id>
            <url>https://maven.aliyun.com/repository/public</url>
            <releases>
                <enabled>true</enabled>
            </releases>
            <snapshots>
                <enabled>false</enabled>
            </snapshots>
        </repository>
    </repositories>
    <pluginRepositories>
        <pluginRepository>
            <id>aliyun-repos</id>
            <url>https://maven.aliyun.com/repository/public</url>
            <releases>
                <enabled>true</enabled>
            </releases>
            <snapshots>
                <enabled>false</enabled>
            </snapshots>
        </pluginRepository>
    </pluginRepositories>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

Tight Coupling 紧耦合

在Spring框架以前，使用排序算法需要将算法实例化

public class ComplexBusinessService {
  SortAlgorithm sortAlgorithm = new BubbleSortAlgorithm;
}
public class BubbleSortAlgorithm implements SortAlgorithm {...}

Good code has loose coupling.

移除依赖项的实例化可以移除紧耦合

public class ComplexBusinessService {
  SortAlgorithm sortAlgorithm; // = new BubbleSortAlgorithm();
  
  public ComplexBusinessService(SortAlgorithm sortAlgorithm) { // 创建构造函数
      this.sortAlgorithm = sortAlgorithm;
  }

public classBubbleSortAlgorithm implements SortAlgorithm {...}

Spring Framework instantiates objects and populates the dependencies.

网络搜索

• 有时候站内搜索没有搜索引擎准确，可以使用搜索引擎过滤网站
  过滤站点：

http://<ENGINE.URL>/search?text=site%3A<SITE.URL>%20{query}

启动应用

信息系统架构

• 信息化系统：前台 + 后台 + 数据库
• B/S 模式
• 前端 -> Server[Apache->PHP(TP6.0)] -> SQL DataBase
• 运行逻辑：
  • Client发送require请求(http协议)，包含header（length、refer信息）、body（数据）
  • Apache接受请求，给PHP做处理
  • PHP读取、处理数据；判断数据是否损毁、是否需要退回
  • 数据更新到前端，并返回结果(success/fail)

“When in doubt go to the library.” – J.K.Rowling

Catalog

Article1: What Are You Going to Do With That？

What Are You Going to Do With That？

William Deresiewicz（《国家》杂志撰稿人和《新共和》杂志编辑）在斯坦福大学的演讲

The question my title poses, of course, is the one that is classically aimed at humanities majors. What practical value could there possibly be in studying literature or art or philosophy? So you must be wondering why I’m bothering to raise it here, at Stanford, this renowned citadel of science and technology. What doubt can there be that the world will offer you many opportunities to use your degree?

（学习文学、艺术或哲学能有什么用呢？所以你肯定纳闷，我为什么在在以科技堡垒而闻名的斯坦福提出这个问题呢？在大学学位给人带来众多机会的问题上还有什么可怀疑的吗？）

But that’s not the question I’m asking. By “do” I don’t mean a job, and by “that” I don’t mean your major. We are more than our jobs, and education is more than a major. Education is more than college, more even than the totality of your formal schooling, from kindergarten through graduate school. By “What are you going to do,” I mean, what kind of life are you going to lead? And by “that,” I mean everything in your training, formal and informal, that has brought you to be sitting here today, and everything you’re going to be doing for the rest of the time that you’re in school.

（但那不是我提出的问题。这里的“做”并不是指工作，“那”并不是指你的专业。我们不仅仅是要个工作，教育不仅仅是学一门专业。教育也不仅仅是上大学，甚至也不仅是从幼儿园到研究生院的正规学校教育。我说的“你要做什么”的意思是你要过什么样的生活？我所说的“那”指的是你得到的正规或非正规的任何训练， 那些把你送到这里来的东西，你在学校的剩余时间里将要做的任何事。）

笔记

命令

hexo new "postName" # 新建文章
hexo new page "pageName" # 新建页面
hexo generate # 生成静态页面至public目录
hexo server # 开启预览访问端口（默认端口4000，'ctrl + c'关闭server）
hexo deploy # 部署到GitHub
hexo help  # 查看帮助
hexo version  # 查看Hexo的版本

按文章更新时间排序

# Home page setting
# path: Root path for your blogs index page. (default = '')
# per_page: Posts displayed per page. (0 = disable pagination)
# order_by: Posts order. (Order by date descending by default)
index_generator:
  path: ''
  per_page: 10
  order_by: -updated # 默认是-date

背景设置

把你挑选的背景图片命名为：background.jpg，放在blog\themes\next\source\images里，在blog\themes\next\source\css_custom文件的custom.styl首部添加

body {
  background:url(/images/background.jpg);
  background-attachment: fixed;
}

符号链接

# Windows，有些文件需要文件名相同才能打开
# -d 目录符号链接
mklink /d C:\file\path\Target C:\file\path\Source

安装主题

1. npm安装在modules下

cd hexo-site
npm install hexo-theme-next

2. git clone安装

cd hexo-site
git clone https://github.com/next-theme/hexo-theme-next themes/next
# Upgrade
cd themes/next
git pull origin master
# Configuration
cp themes/next/_config.yml _config.next.yml

Hexo

我的配置

# 设置英文字体
global:
    family: Source Serif Pro

# layout\_partials\head\head.njk 设置中文字体
{{ next_font() }}
{{ next_vendors('fontawesome') }}
<link href="https://fonts.googleapis.com/css?family=Noto+Serif+SC&display=swap" rel="stylesheet">
# source\css\_variables\base.styl 添加中文字体
$font-family-chinese = "Noto Serif SC"

codes:
    family: IBM Plex Mono

codeblock:
  theme:
    light: stackoverflow-light

Quick Start

npm install hexo-cli -g
hexo init blogFolderName
cd blog
npm install
hexo server

Welcome to Hexo! This is your very first post. Check documentation for more info. If you get any problems when using Hexo, you can find the answer in troubleshooting or you can ask me on GitHub.

Create a new post

$ hexo new "My New Post"

More info: Writing

Run server

$ hexo server

More info: Server

Generate static files

$ hexo generate

More info: Generating

Deploy to remote sites

$ hexo deploy

More info: Deployment

Gradescope Autograder

Spring 2018

44个Assn，偏向数据结构
邀请码：MNXYKX
学校：UC Berkeley
直接输入，不要选择2U-UC Berkeley，否则将提示COURSE ENTRY CODE IS INVALID

Spring 2021

19个Assn，偏向软件工程
邀请码：MB7ZPY

文章收录

The Law of the Broken Futon 浮沙筑高台法则

“Since I’m fine now, can’t I add that missing piece later, when it’s actually needed?” Sometimes, yes. But it’s much harder.
Adding the missing piece later means waiting until the damage is already underway, and hellishly difficult to undo.

A Response to “Why Most Unit Testing is Waste”

(Unit Tests) They are based on programmers’ fantasies about how the function should work. But programmers break down requirements into smaller components all the time – this is how you program. Sometimes there are misunderstandings, but that is the exception, not the rule, in my opinion.

2.1 Mystery of Java Restore

When instantiate an Object, obj = new Object(), obj stores the address of the Object, not the specific data struction.

(That is why all type of variables create memory boxes of 64 bits. It is just the memory of the address.)

Therefore, When we use obj2 = obj, Java simply copy the addr of obj and assign it to obj2 (They are pointing to the same Object), that is why when we change obj2.weight it effects obj.weight too.

Windows

# 模板
netsh dns add encryption server=<IP Address> dohtemplate=<DOH Template> autoupgrade=yes udpfallback=no

# 腾讯
netsh dns add encryption server=1.12.12.12 dohtemplate=https://doh.pub/dns-query autoupgrade=yes udpfallback=no

netsh dns add encryption server=120.53.53.53 dohtemplate=https://doh.360.cn/dns-query autoupgrade=yes udpfallback=no

查看DoH模板：

$ netsh dns show encryption

223.5.5.5 加密设置
----------------------------------------------------------------------
DNS-over-HTTPS 模板     : https://dns.alidns.com/dns-query
自动升级                : yes
UDP 回退                : no

0.0 规范

我要编写一个名为“学习笔记”的 Web 应用程序,让用户能够记录感兴趣的主题,并在学习每个主题的过程中添加日志条目。“学习笔记”的主页对这个网站进行描述,并邀请用户注册或登录。用户登录后,可以创建新主题、添加新条目以及阅读既有的条目。

目录 ll_project 包含 4 个文件, 其中最重要的是 settings.py、urls.py 和 wsgi.py。文件 settings.py 指定 Django 如何与系统交互以及如何管理项目。
在开发项目的过程中,我们将修改其中的一些设置,并添加一些设置。
文件 urls.py 告诉 Django,应创建哪些网页来响应浏览器请求。
文件 wsgi.py 帮助 Django 提供它创建的文件,名称是 web server gateway interface(Web 服务器网关接口)的首字母缩写。

1.0 创建环境

1.1 创建虚拟环境

在独立的项目文件夹下运行

python -m venv ll_env

python -m ensurepip --default-pip # 重装pip

将会创造一个ll_env文件夹
可以使用下面的命令激活虚拟环境。激活虚拟环境后，安装的模组将只在虚拟环境中生效，而不干扰到电脑上Python的模组

source ll_env/bin/activate # Linux系统
source ll_env/Scripts/activate # Windows系统

(ll_env)
work_directory$ # 命令提示符前会显示(ll_env)

使用deactive取消激活虚拟环境

1.2 安装配置Django

pip install --upgrade pip # 更新pip
pip install django # 安装Django
django-admin startproject ll_project . # 初始化Django
python manage.py migrate # 生成数据库
python manage.py runserver # 生成预览，可以在本地8000端口看到网页

Django手册： https://docs.djangoproject.com/en/4.1/ref/models/fields/