云原生时代 Java应用缺点 启动慢, 占用内存多, 需要装jvm
GraalVM  AOT(ahead of time)编译  编译成本地镜像

https://www.graalvm.org/

https://github.com/graalvm/graalvm-ce-builds/releases/tag/vm-22.0.0.2
下载 graalvm-ce-java11-darwin-amd64-22.0.0.2.tar.gz

graalvm-ce-java11-22.0.0.2/Contents/Home/bin/gu install native-image
bin下 会出现 native-image

gu install native-image. 
gu is a utility that you get in a GraalVM. 
JAVA_HOME  set up to point to GraalVM

/Users/xxx/soft/graalvm/graalvm-ce-java11-22.0.0.2/Contents/Home/bin/native-image  graalvm.GraalvmHello

编译报错
Error: Main entry point class 'graalvm.GraalvmHello' not found.
Error: Use -H:+ReportExceptionStackTraces to print stacktrace of underlying exception
Error: Image build request failed with exit status 1

需要先编译生成 class 
/Users/xxx/soft/graalvm/graalvm-ce-java11-22.0.0.2/Contents/Home/bin/javac  graalvm/GraalvmHello.java
再执行 搞定
/Users/xxx/soft/graalvm/graalvm-ce-java11-22.0.0.2/Contents/Home/bin/native-image  graalvm.GraalvmHello

.
├── graalvm
│   ├── GraalvmHello.class
│   └── GraalvmHello.java
├── graalvm.graalvmhello
└── graalvm.graalvmhello.build_artifacts.txt




使用maven 

注意 pom 里 graalvm.version 21.0.0
22.0.0 的找不到

export JAVA_HOME=/Users/xxx/soft/graalvm/graalvm-ce-java11-22.0.0.2/Contents/Home

maven package 

不设置 JAVA_HOME 报错
[ERROR] Failed to execute goal org.graalvm.nativeimage:native-image-maven-plugin:21.0.0:native-image (default) on project graalvmdemo: Could not find executable native-image in /Library/Java/JavaVirtualMachines/jdk1.8.0_221.jdk/Contents/Home/jre/jre/lib/svm/bin/native-image

编译过程比较慢 
生成的可执行文件挺大的，一个helloworld 10M
go hello 大小约 1.8M

./graalvmdemo 
hello,graalvm


各种 hello 可执行文件大小
graalvm 10165344  
go      1865408   
c       49424
c++     55960




例子代码
https://gitee.com/dyyx/hellocode/tree/master/demo/graalvmdemo