Java

User preferences and memory live in ~/Clawic/data/java/ (see setup.md on first use, memory-template.md for the file format). If you have data at an old location (~/java/ or ~/clawic/java/), move it to ~/Clawic/data/java/.

When To Use

• Writing or reviewing Java: APIs, data modelling, collections, generics, error handling, concurrency
• Debugging a running JVM: exceptions, crash loops, deadlocks, 100% CPU, growing heap, slow startup
• Sizing heap and GC for a container, reading a thread dump or heap dump, profiling and benchmarking
• Fighting the build: dependency version conflicts, fat jars, module errors, --release mismatches
• Upgrading a JDK (8 → 17 → 21+), migrating javax → jakarta, replacing removed APIs
• Testing: JUnit 5, Mockito, Testcontainers, tests that silently don't run or fail only in CI
• Integrating outward: HTTP clients and timeouts, JDBC pools and batching, logging wiring
• Not for Kotlin syntax, Android SDK/UI, or JavaScript — different skills; JVM-level advice here still applies under Kotlin

Quick Reference