docker环境下java参数传递与获取

// docker-compose.yml -> environment -> USER
String userEnv = System.getenv("USER");

// java -jar xxx.jar --user=jackson
String userArg = Stream.of(args).filter(arg -> arg.contains("--user")).map(arg -> StringUtils.substringAfter(arg, "=")).collect(Collectors.joining());

// java -jar -Duser=jackson xxx.jar
String userProp = System.getProperty("user", "");

// 按优先级获取
String userName = StringUtils.defaultIfBlank(userEnv, StringUtils.defaultIfBlank(userArg, userProp));

#args
java -jar docker-java-params-0.0.1.jar --user=jackson

#系统属性
java -jar -Duser=jackson docker-java-params-0.0.1.jar

#环境变量、args
docker run -e USER='user001' registry.cn-shanghai.aliyuncs.com/00fly/docker-java-params:0.0.1 --user='jackson'

services:
  docker-java-params:
    image: registry.cn-shanghai.aliyuncs.com/00fly/docker-java-params:0.0.1
    container_name: docker-java-params
    command: --user="user by args"
    entrypoint: java -server -Djava.security.egd=file:/dev/./urandom -Xshareclasses -Xquickstart -Duser="user by prop" -jar /app.jar
    deploy:
      resources:
        limits:
          cpus: '1.0'
          memory: 32M
        reservations:
          cpus: '0.05'
          memory: 32M
    restart: on-failure
    environment:
    - USER=user by env
    logging:
      driver: json-file
      options:
        max-size: 5m
        max-file: '1'

docker-compose up -d && docker logs -f docker-java-params
[+] Running 1/1
 ✔ Container docker-java-params  Started   
[main] INFO com.fly.simple.MainRun - userEnv: user by env
[main] INFO com.fly.simple.MainRun - userArg: user by args
[main] INFO com.fly.simple.MainRun - userProp: user by prop
[main] INFO com.fly.simple.MainRun - userName: user by env

services:
  docker-java-params:
    image: registry.cn-shanghai.aliyuncs.com/00fly/docker-java-params:0.0.1
    container_name: docker-java-params
    command: '--user="${USER2}"'
    entrypoint: 'java -server -Djava.security.egd=file:/dev/./urandom -Xshareclasses -Xquickstart -Duser=${USER3} -jar /app.jar'
    deploy:
      resources:
        limits:
          cpus: '1.0'
          memory: 32M
        reservations:
          cpus: '0.05'
          memory: 32M
    restart: on-failure
    environment:
    - USER=${USER1}
    logging:
      driver: json-file
      options:
        max-size: 5m
        max-file: '1'

docker-compose down && USER1='user001' USER2='user002' USER3='user003' docker-compose up -d && docker logs -f docker-java-params 

public class Main {
    public static void main(String[] args) {
        if (args.length > 0) {
            System.out.println("Hello, " + args[0] + "!");
        } else {
            System.out.println("Hello, Docker Java!");
        }
    }
}

FROM openjdk:8-jdk-alpine
COPY Main.java /
RUN javac Main.java
CMD ["java", "Main"]

docker build -t my-java-app .

docker run my-java-app Docker

FROM openjdk:11
COPY ./myapp.jar /app/myapp.jar
ENV APP_CONFIG_PATH=/app/config/application.properties
CMD ["java", "-jar", "/app/myapp.jar"]

docker run -e APP_CONFIG_PATH=/path/to/config -p 8080:8080 my-java-app

public class MyApp {
    public static void main(String[] args) {
        String configPath = System.getProperty("app.config.path", "default/path/to/config");
        System.out.println("Config Path: " + configPath);
        // 这里可以根据 configPath 加载实际配置文件
    }
}

version: '3'
services:
  myapp:
    image: my-java-app
    environment:
      - APP_CONFIG_PATH=/path/to/config
    ports:
      - "8080:8080"