performance4GraalVmNativeImage

1package pkg19performance;2 3/*4 * performance4GraalVmNativeImage.java5 * -----------------------------------6 * GraalVM native-image: ahead-of-time compilation to a standalone binary.7 *8 * DEFINITION:9 *   native-image compiles Java to a native executable with fast startup and10 *   lower memory footprint — ideal for CLI tools, serverless, containers.11 *12 * KEY POINTS:13 *   - Trade-off: longer build, reflection/config needed for dynamic features.14 *   - Reachability metadata: reflect-config.json, resource-config.json.15 *   - Not all Java features at runtime (some agents, deep reflection need config).16 *17 * Build (requires GraalVM + native-image):18 *   native-image -jar myapp.jar19 *   ./myapp   # starts in milliseconds20 */21public class performance4GraalVmNativeImage {22 23    public static void main(String[] args) {24        System.out.println("GraalVM native-image benefits:");25        System.out.println("  - Startup: ms instead of seconds (no JVM warmup phase)");26        System.out.println("  - Memory: smaller RSS (no full HotSpot runtime)");27        System.out.println("  - Single deployable binary");28 29        System.out.println("\nWhen NOT to use:");30        System.out.println("  - Heavy reflection/dynamic proxies without config");31        System.out.println("  - Apps that rely on JIT peak performance after long warmup");32        System.out.println("  - Frequent dynamic class loading");33 34        System.out.println("\nJMH benchmarks for micro-benchmarks: see pkg19performance/jmh-demo/");35        System.out.println("Hello from JVM — same code can be compiled with native-image.");36    }37}