本屆 #JCConf 邀請到 Koichi Sakata 分享 Reading Java Class Files for Fun: From CAFEBABE to invokedynamic

講題簡介：

Java developers usually write source code and let javac and the JVM handle the rest. But the generated class file contains many interesting details: the constant pool, methods, attributes, bytecode instructions, stack-based execution, synthetic methods, and invokedynamic.

In this session, we will take a guided tour of Java class files using small Java programs and javap. We will start with the basic structure of a class file, including the magic number, version, constant pool, methods, and attributes. Then we will read simple bytecode instructions as stack-machine operations, so that attendees can understand how Java code is represented after compilation.

After building this foundation, we will look at invokedynamic, one of the most interesting bytecode instructions added to the JVM. We will examine how modern Java features such as string concatenation and lambdas are represented in class files, and what bootstrap methods and call sites roughly do behind the scenes.

The goal is not to memorize the JVM specification. The goal is to enjoy discovering what Java actually becomes after compilation. After this session, attendees should be able to inspect class files by themselves and use that knowledge as a foundation for understanding Java language features, JVM behavior, performance topics, and bytecode-based tools.

購票請洽：
https://twjug.kktix.cc/events/jcconf-2026

#JCConf #JCConf2026 #Java #AI #JVM #Performance