Let me walk you through what happens when you open JavaBox in a browser tab. Your browser loads a Cloudflare Worker. That Worker serves a 227MB WebAssembly blob. That blob contains an Emscripten-compiled build of QEMU. QEMU boots a Linux kernel. The Linux kernel boots Alpine Linux 3.21. Alpine Linux has OpenJDK 21 on it. And OpenJDK compiles and runs your Java code.
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，详情可参考体育直播
11:15, 3 марта 2026Интернет и СМИ
Фото: Ronen Zvulun / Reuters