打開Docker的配置文件：
vim /usr/lib/systemd/system/docker.service
將下面這行注釋掉：
# ExecStart=/usr/bin/dockerd -H fd:// --containerd=/run/containerd/containerd.sock
新寫一行：
ExecStart=/usr/bin/dockerd -H tcp://0.0.0.0:2375 -H unix:///var/run/docker.sock
重新加載配置文件和啟動(dòng)：
systemctl daemon-reload
systemctl start docker

<docker.image.prefix>demo</docker.image.prefix>

<plugin>
 <groupId>com.spotify</groupId>
 <artifactId>docker-maven-plugin</artifactId>
 <version>1.2.1</version>
 <configuration>
   <imageName>${docker.image.prefix}/${project.artifactId}</imageName>
   <dockerDirectory></dockerDirectory>
   <resources>
     <resource>
       <targetPath>/</targetPath>
       <directory>${project.build.directory}</directory>
       <include>${project.build.finalName}.jar</include>
     </resource>
   </resources>
 </configuration>
</plugin>

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
 <modelVersion>4.0.0</modelVersion>
 <parent>
   <groupId>org.springframework.boot</groupId>
   <artifactId>spring-boot-starter-parent</artifactId>
   <version>2.2.1.RELEASE</version>
   <relativePath/> <!-- lookup parent from repository -->
 </parent>
 <groupId>com.example</groupId>
 <artifactId>demo</artifactId>
 <version>0.0.1</version>
 <name>demo</name>
 <description>Demo project for Spring Boot</description>

 <properties>
   <java.version>1.8</java.version>
   <docker.image.prefix>demo</docker.image.prefix>
 </properties>

 <dependencies>

   <dependency>
     <groupId>org.springframework.boot</groupId>
     <artifactId>spring-boot-starter</artifactId>
   </dependency>

   <dependency>
     <groupId>org.springframework.boot</groupId>
     <artifactId>spring-boot-starter-web</artifactId>
   </dependency>

   <dependency>
     <groupId>org.springframework.boot</groupId>
     <artifactId>spring-boot-starter-test</artifactId>
     <scope>test</scope>
     <exclusions>
       <exclusion>
         <groupId>org.junit.vintage</groupId>
         <artifactId>junit-vintage-engine</artifactId>
       </exclusion>
     </exclusions>
   </dependency>
 </dependencies>

 <build>
   <plugins>
     <plugin>
       <groupId>org.springframework.boot</groupId>
       <artifactId>spring-boot-maven-plugin</artifactId>
     </plugin>
     <plugin>
       <groupId>com.spotify</groupId>
       <artifactId>docker-maven-plugin</artifactId>
       <version>1.2.1</version>
       <configuration>
         <imageName>${docker.image.prefix}/${project.artifactId}</imageName>
         <dockerDirectory></dockerDirectory>
         <resources>
           <resource>
             <targetPath>/</targetPath>
             <directory>${project.build.directory}</directory>
             <include>${project.build.finalName}.jar</include>
           </resource>
         </resources>
       </configuration>
     </plugin>
   </plugins>
 </build>

</project>

#指定基礎(chǔ)鏡像，在其上進(jìn)行定制
FROM java:8

#維護(hù)者信息
MAINTAINER zhouzhaodong <xiuaiba@163.com>

#這里的 /tmp 目錄就會(huì)在運(yùn)行時(shí)自動(dòng)掛載為匿名卷，任何向 /tmp 中寫入的信息都不會(huì)記錄進(jìn)容器存儲(chǔ)層
VOLUME /tmp

#復(fù)制上下文目錄下的target/demo-1.0.0.jar 到容器里
COPY target/demo-0.0.1.jar demo-1.0.0.jar

#bash方式執(zhí)行，使demo-1.0.0.jar可訪問
#RUN新建立一層，在其上執(zhí)行這些命令，執(zhí)行結(jié)束后， commit 這一層的修改，構(gòu)成新的鏡像。
RUN bash -c "touch /demo-1.0.0.jar"

#聲明運(yùn)行時(shí)容器提供服務(wù)端口，這只是一個(gè)聲明，在運(yùn)行時(shí)并不會(huì)因?yàn)檫@個(gè)聲明應(yīng)用就會(huì)開啟這個(gè)端口的服務(wù)
EXPOSE 8080

#指定容器啟動(dòng)程序及參數(shù)  <ENTRYPOINT> "<CMD>"
ENTRYPOINT ["java","-jar","demo-1.0.0.jar"]

@RestController
public class testController {

  @RequestMapping("/")
  public String test(){
    return "test Docker";
  }

}