The compiler first searches the Java platform packages (in rt.jar and other JAR files), which contain Java’s standard class library types (such as java.lang‘s System class). It then searches ...

java.lang: A collection of language-related classes, such as Object and String, organized in the java package’s lang subpackage; ... the compiler stores java.net with Socket in the classfile.

Use the WebAssembly API to invoke your Java code from JavaScript. Compile your Java code into a WebAssembly WASM file. Package and deploy your HTML and WASM files together and view your webpage.