167 posts
To understand why Optional exists, you first need to understand NPE. Many object-oriented languages have a null value: a pointer on the stack that points at a heap address that doesn't exist. Use that object and you get a NullPointerException. If you fail to anticipate the null case, your program crashes.
This post uses the IP2Location LITE database and queries it by reading the BIN file directly. The code is a trimmed-down version of the official sample, published to Maven Central.
GitLab didn't disappoint me, but it didn't wow me either — it's the straight-A student, solid but predictable. There's almost no localization, so no pleasant surprises: powerful features, steep learning curve, incomplete Chinese translation. JiHu still has a long way to go on localization.
The China edition of GitLab, operated by JiHu Information Technology (Hubei) Co. and branded "JiHu", focuses on enterprise DevOps. I was lucky enough to join the SaaS beta — here's my look at the domestic version of JiHu.
Google has long supported proactive URL submission, but it's not a point-and-click UI for ordinary users — it's an API for programmers. Plenty of webmasters aren't developers, and since Google requires ownership verification, I can't just build a UI where people paste their own private key. Instead I wrapped Google's API to make it easier to use.
Tired of domestic databases shipping no macOS installer while doing localization work? This tutorial runs Kingbase V8 R3 (a Chinese domestic database) in a Docker container on macOS, giving your MacBook a working Kingbase development environment.
Last time we learned synchronized thread coordination, which is enough to build real things — the most classic being the producer-consumer model. One producer keeps making resources, one consumer keeps taking them, two threads simulating that relationship, like a chef and a server: the chef keeps cooking, and the server takes the dish away once it's plated.
Anyone who's touched multithreading has heard the synchronized keyword. We'll start with a broken example to show what happens without it, fix it with synchronized, and then let synchronized lead us into deadlock.
Why am I griping about Gitee on my own blog instead of reporting it to Gitee? Because that's one of the things I'm griping about. Their issue workflow is broken too: I filed an issue, an official replied and rejected it, and once rejected I could no longer respond — so here I am, griping on my own blog.
Let's be clear about this: Java threads have 6 states. Online — including the copy-paste crowd on CSDN who mindlessly repost who-knows-what — everyone says 5. I went and read the docs myself, and I'm certain it's 6.
