场景

公司要对springboot项目依赖的jar包进行升级，但是遇到一个问题，项目打包之后，没办法看到他里面依赖的jar包，版本到底是不是升上去了，没办法看到。

下面是项目打的jar包

我们通过反编译工具jdgui，来看一下jar包文件内容，我们发现里面根本没有看到依赖的jar包

既然看不到依赖的jar包，那么就没办法确定，jar包版本是否升级成功，那应该怎么办呢？

解决办法

maven有一个办法，就是可以将依赖的jar包输出的指定的目录。具体配置如下：

<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.hidata.kafka</groupId>
    <artifactId>hijob-kafka</artifactId>
    <version>0.1</version>

    <dependencyManagement>
		<dependencies>
			<dependency>
				<groupId>org.springframework.boot</groupId>
				<artifactId>spring-boot-dependencies</artifactId>
				<version>2.7.18</version>
				<type>pom</type>
				<scope>import</scope>
			</dependency>
		</dependencies>
	</dependencyManagement>

    <properties>
		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
		<java.version>1.8</java.version>
		<bboss.version>5.8.6</bboss.version>
	</properties>

    <dependencies>
        <!-- spring boot -->
        <dependency>
            .....
        </dependency>

	</dependencies>

    <build>
    	<resources>
			<resource>
				<directory>${project.basedir}/src/main/resources</directory>
				<filtering>true</filtering>
				<excludes>
                    <exclude>static/**</exclude>
                </excludes>
			</resource>

			<resource>
				<directory>${project.basedir}/src/main/resources</directory>
                <filtering>false</filtering>
                <includes>
                    <include>static/**</include>
                </includes>
			</resource>
		</resources>
        <plugins>
			<plugin>
		      <groupId>org.springframework.boot</groupId>
		      <artifactId>spring-boot-maven-plugin</artifactId>
		      <configuration>
		        <mainClass>com.hidata.kafka.HijobKafkaApplication</mainClass>
		        <layout>ZIP</layout>
		        <includes>
		          <include>
		            <groupId>nothing</groupId>
		            <artifactId>nothing</artifactId>
		          </include>
		        </includes>
		      </configuration>
		      <executions>
		        <execution>
		          <goals>
		            <goal>repackage</goal>
		          </goals>
		        </execution>
		      </executions>
		    </plugin>
			<plugin>
				<groupId>org.apache.maven.plugins</groupId>
				<artifactId>maven-compiler-plugin</artifactId>
				<configuration>
					<source>7</source>
					<target>7</target>
				</configuration>
			</plugin>
			<plugin>
				<groupId>org.apache.maven.plugins</groupId>
				<artifactId>maven-dependency-plugin</artifactId>
				<executions>
					<execution>
						<id>copy-dependencies</id>
						<phase>package</phase>
						<goals>
							<goal>copy-dependencies</goal>
						</goals>
						<configuration>
							<!--target/lib是依赖jar包的输出目录，根据自己喜好配置-->
							<outputDirectory>target/lib</outputDirectory>
							<excludeTransitive>false</excludeTransitive>
							<stripVersion>false</stripVersion>
							<includeScope>runtime</includeScope>
						</configuration>
					</execution>
				</executions>
			</plugin>
		</plugins>

    </build>
</project>

重要的事再说一遍，其实核心就是这一句配置

<plugin>
				<groupId>org.apache.maven.plugins</groupId>
				<artifactId>maven-dependency-plugin</artifactId>
				<executions>
					<execution>
						<id>copy-dependencies</id>
						<phase>package</phase>
						<goals>
							<goal>copy-dependencies</goal>
						</goals>
						<configuration>
							<!--target/lib是依赖jar包的输出目录，根据自己喜好配置-->
							<outputDirectory>target/lib</outputDirectory>
							<excludeTransitive>false</excludeTransitive>
							<stripVersion>false</stripVersion>
							<includeScope>runtime</includeScope>
						</configuration>
					</execution>
				</executions>
			</plugin>

我们再打包一下看看效果：

我们发现target多了一个文件夹lib，其实他就是存放项目所依赖的jar包的。打开lib文件夹，发现里面全部都是jar包

这样就可以知道，jar包的版本到底有没有升级成功了。