背景

分布式项目、微服务项目一般都会引用许多公共依赖，每次maven打出来的jar包上百M，不利于运维工作、可以在打包时隔离项目本身的jar和依赖的公用jar包，这样项目本身包可以做到很精简。

本文主要把项目依赖的包和项目的配置文件在打包时导出到本身springboot 的jar包 外。

本文项目中导入依赖用到了两种方式，一是直接通过maven库，二是通过导入本地第三方jar

配置

全部配置

我在系统根目录下创建了一个boot的文件夹，mvn打包之后会在boot下创建名称为lib、boot-demo的两个文件夹，lib用来存放所有依赖的jar，boot-demo用来存放springboot的jar和application.properties配置文件 

用到了

maven-compiler-plugin：负责编译源码

spring-boot-maven-plugin ：负责编译springbootjar

maven-jar-plugin：负责把项目依赖的jar写到MANIFEST.MF文件

maven-dependency-plugin：负责导出项目依赖的jar

maven-resources-plugin：负责导出项目配置文件

<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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.luck</groupId>
    <artifactId>boot-demo</artifactId>
    <version>1.0-SNAPSHOT</version>

    <name>boot-demo</name>

    <properties>
        <global-jar-output>/boot</global-jar-output>
        <!-- 注意点 . 和 空格 -->
        <system-jar-classpath>. ../lib/mytest-1.0.jar</system-jar-classpath>
        <java.home>${env.JAVA_HOME}</java.home>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <java.version>1.8</java.version>
    </properties>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-dependencies</artifactId>
                <version>2.3.0.RELEASE</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!-- 直接引入SDK，对应上面配置的properties -->
        <dependency>
            <groupId>com.luck</groupId>
            <artifactId>mytest</artifactId>
            <version>1.0</version>
            <scope>system</scope>
            <systemPath>${basedir}/lib/otherjar.jar</systemPath>
        </dependency>
    </dependencies>
    <build>
        <resources>
            <resource>
                <directory>src/main/java</directory>
                <includes>
                    <include>**/*.xml</include>
                </includes>
            </resource>
            <resource>
                <directory>src/main/resources</directory>
                <includes>
                    <include>**/*.*</include>
                </includes>
                <!-- 忽略配置文件 -->
                <excludes>
                    <exclude>*.properties</exclude>
                </excludes>
            </resource>
            <resource>
                <directory>src/main/${package.environment}</directory>
                <includes>
                    <include>**/*.*</include>
                </includes>
                <excludes>
                    <exclude>*.properties</exclude>
                </excludes>
                <targetPath>${project.basedir}/target/classes</targetPath>
                <filtering>true</filtering>
            </resource>
        </resources>
        <plugins>
            <!-- 编译源码 -->
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.1</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                    <encoding>UTF8</encoding>
                    <compilerArguments>
                        <bootclasspath>${java.home}\jre\lib\rt.jar;${java.home}\jre\lib\jce.jar</bootclasspath>
                    </compilerArguments>
                </configuration>
            </plugin>
            <!-- 导出springboot的jar -->
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <!-- 启动类 -->
                    <mainClass>com.luck.MainApplication</mainClass>
                    <!-- 打包方式，zip说明jar以PropertiesLauncher启动 -->
                    <layout>ZIP</layout>
                    <!-- 忽略所有jar，在springboot包中不包含任何jar依赖 -->
                    <includes>
                         <include>
                             <groupId>nojar</groupId>
                             <artifactId>nojar</artifactId>
                         </include>
                    </includes>
                    <!-- springboot jar导出目录 -->
                    <outputDirectory>${global-jar-output}/${project.artifactId}</outputDirectory>
                </configuration>
                <executions>
                    <execution>
                        <goals>
                            <goal>repackage</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-jar-plugin</artifactId>
                <configuration>
                    <archive>
                        <!-- META-INF/MANIFEST.MF中添加Class-Path: {项目依赖的所有jar名称}-->
                        <manifest>
                            <addClasspath>true</addClasspath>
                            <classpathPrefix>../lib/</classpathPrefix>
                            <useUniqueVersions>false</useUniqueVersions>
                        </manifest>
                        <!-- META-INF/MANIFEST.MF中添加Class-Path: {第三方jar名称，上方properties的配置}-->
                        <manifestEntries>
                            <Class-Path>${system-jar-classpath}</Class-Path>
                        </manifestEntries>
                    </archive>
                </configuration>
            </plugin>
            <!-- 导出项目依赖的jar到/boot/lib目录下 -->
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-dependency-plugin</artifactId>
                <executions>
                    <execution>
                        <id>copy-lib</id>
                        <phase>package</phase>
                        <goals>
                            <goal>copy-dependencies</goal>
                        </goals>
                    </execution>
                </executions>
                 <configuration>
                     <outputDirectory>${global-jar-output}/lib</outputDirectory>
                     <excludeTransitive>false</excludeTransitive>
                     <stripVersion>false</stripVersion>
                     <silent>false</silent>
                 </configuration>
            </plugin>
            <!-- 导出项目配置文件 -->
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-resources-plugin</artifactId>
                <executions>
                    <execution>
                        <id>copy-config</id>
                        <phase>package</phase>
                        <goals>
                            <goal>copy-resources</goal>
                        </goals>
                        <configuration>
                            <resources>
                                <resource>
                                    <directory>src/main/resources</directory>
                                    <includes>
                                        <include>*.properties</include>
                                    </includes>
                                </resource>
                            </resources>
                            <outputDirectory>${global-jar-output}/${project.artifactId}</outputDirectory>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>

    <profiles>
        <profile>
            <id>test</id>
            <properties>
                <package.environment>res-test</package.environment>
            </properties>
        </profile>
        <profile>
            <id>dev</id>
            <activation>
                <activeByDefault>true</activeByDefault>
            </activation>
            <properties>
                <package.environment>resources</package.environment>
            </properties>
        </profile>
    </profiles>
</project>

生成 

 

 

 

 

 

 

Java中读取application.properties文件

java读取外部配置文件需要用到

org.springframework.core.io.ClassPathResource.ClassPathResource这个类

InputStream in = new ClassPathResource("application.properties").getInputStream()

参考文章

SpringBoot 部署 Jar 文件，瘦身优化指南 ！ - 知乎