René's URL Explorer Experiment

Title: toBeBetterJavaer/docs/java8/optional.md at master · coding-kill/toBeBetterJavaer · GitHub

Open Graph Title: toBeBetterJavaer/docs/java8/optional.md at master · coding-kill/toBeBetterJavaer

X Title: toBeBetterJavaer/docs/java8/optional.md at master · coding-kill/toBeBetterJavaer

Description: 一份通俗易懂、风趣幽默的Java学习指南，内容涵盖Java基础、Java并发编程、Java虚拟机、Java企业级开发、Java面试等核心知识点。学Java，就认准Java 程序员进阶之路😄 - toBeBetterJavaer/docs/java8/optional.md at master · coding-kill/toBeBetterJavaer

Open Graph Description: 一份通俗易懂、风趣幽默的Java学习指南，内容涵盖Java基础、Java并发编程、Java虚拟机、Java企业级开发、Java面试等核心知识点。学Java，就认准Java 程序员进阶之路😄 - coding-kill/toBeBetterJavaer

X Description: 一份通俗易懂、风趣幽默的Java学习指南，内容涵盖Java基础、Java并发编程、Java虚拟机、Java企业级开发、Java面试等核心知识点。学Java，就认准Java 程序员进阶之路😄 - coding-kill/toBeBetterJavaer

Opengraph URL: https://github.com/coding-kill/toBeBetterJavaer/blob/master/docs/java8/optional.md

X: @github

direct link

Domain: github.com

route-pattern	/:user_id/:repository/blob/name(/path)
route-controller	blob
route-action	show
fetch-nonce	v2:20294467-f8bf-a1f3-af53-fb210ae0bf23
current-catalog-service-hash	f3abb0cc802f3d7b95fc8762b94bdcb13bf39634c40c357301c4aa1d67a256fb
request-id	A90C:14CF7C:368F9F:4A9654:6A5FAC72
html-safe-nonce	3aadd32c0f74277a9891bd6d60966ba6fd6b4eb5856e6f9dbeac0519c23ca1f7
visitor-payload	eyJyZWZlcnJlciI6IiIsInJlcXVlc3RfaWQiOiJBOTBDOjE0Q0Y3QzozNjhGOUY6NEE5NjU0OjZBNUZBQzcyIiwidmlzaXRvcl9pZCI6IjYzMTkyMzc3MTg1NjU5NTY3MjIiLCJyZWdpb25fZWRnZSI6ImlhZCIsInJlZ2lvbl9yZW5kZXIiOiJpYWQifQ==
visitor-hmac	b9475a9cde75055e7f6340d012e8738f5735c3f1cbf4216176cdc1af290e96bc
hovercard-subject-tag	repository:576113919
github-keyboard-shortcuts	repository,source-code,file-tree,copilot
google-site-verification	Apib7-x98H0j5cPqHWwSMm6dNU4GmODRoqxLiDzdx9I
octolytics-url	https://collector.github.com/github/collect
analytics-location	///blob/show
fb:app_id	1401488693436528
apple-itunes-app	app-id=1477376905, app-argument=https://github.com/coding-kill/toBeBetterJavaer/blob/master/docs/java8/optional.md
twitter:image	https://opengraph.githubassets.com/0d5f4f5d7fd340f0543bd12b63177a89787a2dbd9ce9202604d19daac8ead2ab/coding-kill/toBeBetterJavaer
twitter:card	summary_large_image
og:image	https://opengraph.githubassets.com/0d5f4f5d7fd340f0543bd12b63177a89787a2dbd9ce9202604d19daac8ead2ab/coding-kill/toBeBetterJavaer
og:image:alt	一份通俗易懂、风趣幽默的Java学习指南，内容涵盖Java基础、Java并发编程、Java虚拟机、Java企业级开发、Java面试等核心知识点。学Java，就认准Java 程序员进阶之路😄 - coding-kill/toBeBetterJavaer
og:image:width	1200
og:image:height	600
og:site_name	GitHub
og:type	object
hostname	github.com
expected-hostname	github.com
None	9b835c054d57dfb6ce72ba8f0eb8f16f0370860631609eb10df818738c61c68d
turbo-cache-control	no-cache
go-import	github.com/coding-kill/toBeBetterJavaer git https://github.com/coding-kill/toBeBetterJavaer.git
octolytics-dimension-user_id	33112654
octolytics-dimension-user_login	coding-kill
octolytics-dimension-repository_id	576113919
octolytics-dimension-repository_nwo	coding-kill/toBeBetterJavaer
octolytics-dimension-repository_public	true
octolytics-dimension-repository_is_fork	true
octolytics-dimension-repository_parent_id	156627365
octolytics-dimension-repository_parent_nwo	itwanger/toBeBetterJavaer
octolytics-dimension-repository_network_root_id	156627365
octolytics-dimension-repository_network_root_nwo	itwanger/toBeBetterJavaer
turbo-body-classes	logged-out env-production page-responsive
disable-turbo	false
browser-stats-url	https://api.github.com/_private/browser/stats
browser-errors-url	https://api.github.com/_private/browser/errors
release	4df9bc0bde4bfd7cd95e75afdd7f103984ece3a1
ui-target	full
theme-color	#1e2327
color-scheme	light dark

Links:

Skip to content	https://github.com/coding-kill/toBeBetterJavaer/blob/master/docs/java8/optional.md#start-of-content
	https://github.com/
Sign in	https://github.com/login?return_to=https%3A%2F%2Fgithub.com%2Fcoding-kill%2FtoBeBetterJavaer%2Fblob%2Fmaster%2Fdocs%2Fjava8%2Foptional.md
GitHub CopilotWrite better code with AI	https://github.com/features/copilot
GitHub Copilot appDirect agents from issue to merge	https://github.com/features/ai/github-app
MCP RegistryNewIntegrate external tools	https://github.com/mcp
ActionsAutomate any workflow	https://github.com/features/actions
CodespacesInstant dev environments	https://github.com/features/codespaces
IssuesPlan and track work	https://github.com/features/issues
Code ReviewManage code changes	https://github.com/features/code-review
Code QualityEnforce quality at merge	https://github.com/features/code-quality
GitHub Advanced SecurityFind and fix vulnerabilities	https://github.com/security/advanced-security
Code securitySecure your code as you build	https://github.com/security/advanced-security/code-security
Secret protectionStop leaks before they start	https://github.com/security/advanced-security/secret-protection
Why GitHub	https://github.com/why-github
Documentation	https://docs.github.com
Blog	https://github.blog
Changelog	https://github.blog/changelog
Marketplace	https://github.com/marketplace
View all features	https://github.com/features
Enterprises	https://github.com/enterprise
Small and medium teams	https://github.com/team
Startups	https://github.com/enterprise/startups
Nonprofits	https://github.com/solutions/industry/nonprofits
App Modernization	https://github.com/solutions/use-case/app-modernization
DevSecOps	https://github.com/solutions/use-case/devsecops
DevOps	https://github.com/solutions/use-case/devops
CI/CD	https://github.com/solutions/use-case/ci-cd
View all use cases	https://github.com/solutions/use-case
Healthcare	https://github.com/solutions/industry/healthcare
Financial services	https://github.com/solutions/industry/financial-services
Manufacturing	https://github.com/solutions/industry/manufacturing
Government	https://github.com/solutions/industry/government
View all industries	https://github.com/solutions/industry
View all solutions	https://github.com/solutions
AI	https://github.com/resources/articles?topic=ai
Software Development	https://github.com/resources/articles?topic=software-development
DevOps	https://github.com/resources/articles?topic=devops
Security	https://github.com/resources/articles?topic=security
View all topics	https://github.com/resources/articles
Customer stories	https://github.com/customer-stories
Events & webinars	https://github.com/resources/events
Ebooks & reports	https://github.com/resources/whitepapers
Business insights	https://github.com/solutions/executive-insights
GitHub Skills	https://skills.github.com
Documentation	https://docs.github.com
Customer support	https://support.github.com
Community forum	https://github.com/orgs/community/discussions
Trust center	https://github.com/trust-center
Partners	https://github.com/partners
View all resources	https://github.com/resources
GitHub SponsorsFund open source developers	https://github.com/open-source/sponsors
Security Lab	https://securitylab.github.com
Maintainer Community	https://maintainers.github.com
Accelerator	https://github.com/open-source/accelerator
GitHub Stars	https://stars.github.com
Archive Program	https://archiveprogram.github.com
Topics	https://github.com/topics
Trending	https://github.com/trending
Collections	https://github.com/collections
Enterprise platformAI-powered developer platform	https://github.com/enterprise
GitHub Advanced SecurityEnterprise-grade security features	https://github.com/security/advanced-security
Copilot for BusinessEnterprise-grade AI features	https://github.com/features/copilot/copilot-business
Premium SupportEnterprise-grade 24/7 support	https://github.com/enterprise/premium-support
Pricing	https://github.com/pricing
Search syntax tips	https://docs.github.com/search-github/github-code-search/understanding-github-code-search-syntax
documentation	https://docs.github.com/search-github/github-code-search/understanding-github-code-search-syntax
Sign in	https://github.com/login?return_to=https%3A%2F%2Fgithub.com%2Fcoding-kill%2FtoBeBetterJavaer%2Fblob%2Fmaster%2Fdocs%2Fjava8%2Foptional.md
Sign up	https://github.com/signup?ref_cta=Sign+up&ref_loc=header+logged+out&ref_page=%2F%3Cuser-name%3E%2F%3Crepo-name%3E%2Fblob%2Fshow&source=header-repo&source_repo=coding-kill%2FtoBeBetterJavaer
Reload	https://github.com/coding-kill/toBeBetterJavaer/blob/master/docs/java8/optional.md
Reload	https://github.com/coding-kill/toBeBetterJavaer/blob/master/docs/java8/optional.md
Reload	https://github.com/coding-kill/toBeBetterJavaer/blob/master/docs/java8/optional.md
coding-kill	https://github.com/coding-kill
toBeBetterJavaer	https://github.com/coding-kill/toBeBetterJavaer
itwanger/toBeBetterJavaer	https://github.com/itwanger/toBeBetterJavaer
Notifications	https://github.com/login?return_to=%2Fcoding-kill%2FtoBeBetterJavaer
Fork 0	https://github.com/login?return_to=%2Fcoding-kill%2FtoBeBetterJavaer
Star 0	https://github.com/login?return_to=%2Fcoding-kill%2FtoBeBetterJavaer
Code	https://github.com/coding-kill/toBeBetterJavaer
Pull requests 0	https://github.com/coding-kill/toBeBetterJavaer/pulls
Actions	https://github.com/coding-kill/toBeBetterJavaer/actions
Projects	https://github.com/coding-kill/toBeBetterJavaer/projects
Security and quality 0	https://github.com/coding-kill/toBeBetterJavaer/security
Insights	https://github.com/coding-kill/toBeBetterJavaer/pulse
Code	https://github.com/coding-kill/toBeBetterJavaer
Pull requests	https://github.com/coding-kill/toBeBetterJavaer/pulls
Actions	https://github.com/coding-kill/toBeBetterJavaer/actions
Projects	https://github.com/coding-kill/toBeBetterJavaer/projects
Security and quality	https://github.com/coding-kill/toBeBetterJavaer/security
Insights	https://github.com/coding-kill/toBeBetterJavaer/pulse
	https://github.com/coding-kill/toBeBetterJavaer
toBeBetterJavaer	https://github.com/coding-kill/toBeBetterJavaer/tree/master
docs	https://github.com/coding-kill/toBeBetterJavaer/tree/master/docs
java8	https://github.com/coding-kill/toBeBetterJavaer/tree/master/docs/java8
History	https://github.com/coding-kill/toBeBetterJavaer/commits/master/docs/java8/optional.md
	https://github.com/coding-kill/toBeBetterJavaer/commits/master/docs/java8/optional.md
toBeBetterJavaer	https://github.com/coding-kill/toBeBetterJavaer/tree/master
docs	https://github.com/coding-kill/toBeBetterJavaer/tree/master/docs
java8	https://github.com/coding-kill/toBeBetterJavaer/tree/master/docs/java8
Raw	https://github.com/coding-kill/toBeBetterJavaer/raw/refs/heads/master/docs/java8/optional.md
	https://camo.githubusercontent.com/2a7d4e15a011e9455026ea51234a351cdb03811a2e0b1c054e89b84ac2627b62/687474703a2f2f63646e2e746f62656265747465726a61766165722e636f6d2f746f62656265747465726a61766165722f696d616765732f6a617661382f6f7074696f6e616c2d312e6a7067
	https://github.com/coding-kill/toBeBetterJavaer/blob/master/docs/java8/optional.md#01没有-optional-会有什么问题
	https://github.com/coding-kill/toBeBetterJavaer/blob/master/docs/java8/optional.md#02optional-是如何解决这个问题的
	https://github.com/coding-kill/toBeBetterJavaer/blob/master/docs/java8/optional.md#03创建-optional-对象
	https://github.com/coding-kill/toBeBetterJavaer/blob/master/docs/java8/optional.md#04判断值是否存在
	https://github.com/coding-kill/toBeBetterJavaer/blob/master/docs/java8/optional.md#05非空表达式
	https://github.com/coding-kill/toBeBetterJavaer/blob/master/docs/java8/optional.md#06设置获取默认值
	https://github.com/coding-kill/toBeBetterJavaer/blob/master/docs/java8/optional.md#07获取值
	https://github.com/coding-kill/toBeBetterJavaer/blob/master/docs/java8/optional.md#08过滤值
	https://github.com/coding-kill/toBeBetterJavaer/blob/master/docs/java8/optional.md#09转换值
	https://camo.githubusercontent.com/4a9a5f82eae2f6407ea4c99f7100861130af91506ae6871b8b1ac8c74acd5fd7/687474703a2f2f63646e2e746f62656265747465726a61766165722e636f6d2f746f62656265747465726a61766165722f696d616765732f6a617661382f6f7074696f6e616c2d322e6a7067
可以说是2022年全网最全的学习和找工作的PDF资源了	https://tobebetterjavaer.com/pdf/programmer-111.html
	https://camo.githubusercontent.com/31342bccd2f6da25792cf72d77103f5511d736923b3e0c31a3f848fd876480cd/687474703a2f2f63646e2e746f62656265747465726a61766165722e636f6d2f746f62656265747465726a61766165722f696d616765732f78696e676269616f676f6e677a686f6e6768616f2e706e67
	https://github.com
Terms	https://docs.github.com/site-policy/github-terms/github-terms-of-service
Privacy	https://docs.github.com/site-policy/privacy-policies/github-privacy-statement
Security	https://github.com/security
Status	https://www.githubstatus.com/
Community	https://github.community/
Docs	https://docs.github.com/
Contact	https://support.github.com?tags=dotcom-footer

Viewport: width=device-width

URLs of crawlers that visited me.