[In-Person] JJUG Night Seminar: Tackling Robust Design Boundaries in Modern Java and an AI-Native Future

JJUG (Japan Java User Group) holds this monthly night seminar in person only, at Microsoft Japan's office in Shinagawa's Grand Central Tower. The July session pairs a design-focused talk on modern Java features (records, sealed classes, pattern matching) with a session on Java and AI tooling. The first talk, "Building Real Design Boundaries to Escape 'Layering by Feel'," is given by Yoshitaka Kawashima (Wolf Chief Inc.). It addresses how layered architectures often fail to protect anything meaningful in practice, and walks through building a boundary where untrusted external input is converted into a typed domain, using the decoder library Raoh as the working example, contrasted with Bean Validation. The second talk, "Building an AI Coding Usage Dashboard with Java and Quarkus," is given by Shin Tanimoto (Everforth Inc. / Acroquest Technology Inc., Java Champion). He introduces a self-built tool, the CCC (Codex and Claude Code) Usage Dashboard, and covers how it ingests and aggregates OTLP logs from Codex and Claude Code, the Java and Quarkus implementation, GraalVM Native Image for single-binary packaging, and signed binary distribution for macOS.