Proguard 无法读取类答案

【问题标题】：Proguard can't read classProguard 无法读取类
【发布时间】：2023-03-16 10:03:01
【问题描述】：

我有一个使用番石榴的项目，问题是番石榴占用了大量空间，所以我按照他们在github documentation 中的建议使用了proguard。

问题，一旦我完成了我的 pom.xml 文件并我的目标清理包，它不会在我的目标 proguard 期间构建。

[INFO] Attaching shaded artifact.
[INFO] 
[INFO] --- proguard-maven-plugin:2.0.4:proguard (default) @ Project ---
[INFO] execute ProGuard [-injars, 'C:\Users\Assim Zemouchi\IdeaProjects\Projects\Project - Discord\target\Project-1.0.0-shaded.jar'(!META-INF/maven/**), -outjars, 'C:\Users\Assim Zemouchi\IdeaProjects\Client\Projects\Project - Discord\target\Project-1.0.0-small.jar', -include, 'C:\Users\Assim Zemouchi\IdeaProjects\Client\Projects\Project - Discord\lib\config.pro', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\net\dv8tion\JDA\4.2.0_214\JDA-4.2.0_214.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\org\jetbrains\annotations\16.0.1\annotations-16.0.1.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\org\slf4j\slf4j-api\1.7.25\slf4j-api-1.7.25.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\com\neovisionaries\nv-websocket-client\2.10\nv-websocket-client-2.10.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\com\squareup\okhttp3\okhttp\3.13.0\okhttp-3.13.0.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\com\squareup\okio\okio\1.17.2\okio-1.17.2.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\org\apache\commons\commons-collections4\4.1\commons-collections4-4.1.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\net\sf\trove4j\trove4j\3.0.3\trove4j-3.0.3.jar', -libraryjars, 'C:\Users\Assim Zemouchi\IdeaProjects\Projects\Project - Discord\lib\GAO.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\com\sparkjava\spark-core\2.9.3\spark-core-2.9.3.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\org\eclipse\jetty\jetty-server\9.4.31.v20200723\jetty-server-9.4.31.v20200723.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\org\eclipse\jetty\jetty-http\9.4.31.v20200723\jetty-http-9.4.31.v20200723.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\org\eclipse\jetty\jetty-util\9.4.31.v20200723\jetty-util-9.4.31.v20200723.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\org\eclipse\jetty\jetty-io\9.4.31.v20200723\jetty-io-9.4.31.v20200723.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\org\eclipse\jetty\jetty-webapp\9.4.31.v20200723\jetty-webapp-9.4.31.v20200723.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\org\eclipse\jetty\jetty-xml\9.4.31.v20200723\jetty-xml-9.4.31.v20200723.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\org\eclipse\jetty\jetty-servlet\9.4.31.v20200723\jetty-servlet-9.4.31.v20200723.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\org\eclipse\jetty\jetty-security\9.4.31.v20200723\jetty-security-9.4.31.v20200723.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\org\eclipse\jetty\websocket\websocket-server\9.4.31.v20200723\websocket-server-9.4.31.v20200723.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\org\eclipse\jetty\websocket\websocket-common\9.4.31.v20200723\websocket-common-9.4.31.v20200723.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\org\eclipse\jetty\websocket\websocket-client\9.4.31.v20200723\websocket-client-9.4.31.v20200723.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\org\eclipse\jetty\jetty-client\9.4.31.v20200723\jetty-client-9.4.31.v20200723.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\org\eclipse\jetty\websocket\websocket-servlet\9.4.31.v20200723\websocket-servlet-9.4.31.v20200723.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\org\eclipse\jetty\websocket\websocket-api\9.4.31.v20200723\websocket-api-9.4.31.v20200723.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\com\google\code\gson\gson\2.8.6\gson-2.8.6.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\io\github\portlek\configs-core\4.9.9.6\configs-core-4.9.9.6.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\io\github\portlek\reflection\3.7\reflection-3.7.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\io\github\portlek\replaceable\1.6\replaceable-1.6.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\io\github\portlek\version\1.6\version-1.6.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\io\github\portlek\mapentry\1.8\mapentry-1.8.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\me\carleslc\Simple-YAML\Simple-Configuration\1.7.1\Simple-Configuration-1.7.1.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\io\github\portlek\configs-yaml\4.9.9.6\configs-yaml-4.9.9.6.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\me\carleslc\Simple-YAML\Simple-Yaml\1.7.1\Simple-Yaml-1.7.1.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\org\yaml\snakeyaml\1.26\snakeyaml-1.26.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\org\jsoup\jsoup\1.8.3\jsoup-1.8.3.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\com\atlassian\commonmark\commonmark\0.15.2\commonmark-0.15.2.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\org\nibor\autolink\autolink\0.10.0\autolink-0.10.0.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\mysql\mysql-connector-java\8.0.22\mysql-connector-java-8.0.22.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\com\google\protobuf\protobuf-java\3.11.4\protobuf-java-3.11.4.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\com\zaxxer\HikariCP\3.4.5\HikariCP-3.4.5.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\com\google\guava\guava\30.0-jre\guava-30.0-jre.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\com\google\guava\failureaccess\1.0.1\failureaccess-1.0.1.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\com\google\guava\listenablefuture\9999.0-empty-to-avoid-conflict-with-guava\listenablefuture-9999.0-empty-to-avoid-conflict-with-guava.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\com\google\code\findbugs\jsr305\3.0.2\jsr305-3.0.2.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\org\checkerframework\checker-qual\3.5.0\checker-qual-3.5.0.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\com\google\errorprone\error_prone_annotations\2.3.4\error_prone_annotations-2.3.4.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\com\google\j2objc\j2objc-annotations\1.3\j2objc-annotations-1.3.jar', -libraryjars, 'C:\Users\Assim Zemouchi\.m2\repository\net\sf\proguard\proguard-base\6.2.2\proguard-base-6.2.2.jar', -libraryjars, 'C:\Program Files\Java\jdk1.8.0_251\jre/lib/rt.jar', -libraryjars, 'C:\Program Files\Java\jdk1.8.0_251\jre/lib/jsse.jar', -printmapping, 'C:\Users\Assim Zemouchi\IdeaProjects\Client\Projects\Project - Discord\target\proguard_map.txt', -printseeds, 'C:\Users\Assim Zemouchi\IdeaProjects\Client\Projects\Project - Discord\target\proguard_seeds.txt']
[INFO] proguard jar: C:\Users\Assim Zemouchi\.m2\repository\net\sf\proguard\proguard\4.3\proguard-4.3.jar
 [proguard] ProGuard, version 4.3
 [proguard] Reading program jar [C:\Users\Assim Zemouchi\IdeaProjects\Projects\Project - Discord\target\Project-1.0.0-shaded.jar] (filtered)
 [proguard] Error: Can't read [C:\Users\Assim Zemouchi\IdeaProjects\Client\Projects\Project - Discord\target\Project-1.0.0-shaded.jar(;;;;!META-INF/maven/**)] (Can't process class [fr/misterassm/commands/StatsCommand.class] (Unsupported version number [52.0] for class format))
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time:  3.895 s
[INFO] Finished at: 2020-11-22T14:34:16+01:00
[INFO] ------------------------------------------------------------------------
[WARNING] The requested profile "artifactory" could not be activated because it does not exist.
[ERROR] Failed to execute goal com.pyx4me:proguard-maven-plugin:2.0.4:proguard (default) on project Project: Obfuscation failed (result=1) -> [Help 1]
[ERROR] 
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR] 
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoExecutionException

(Unsupported version number [52.0] for class format) 这是我从中得到的，我不明白为什么，我试图从我的项目中删除这个类，但它是另一个类，之后会有同样的问题。

这是我的 pom.xml：

<properties>
    <project.build.finalName>Project_Discord_${project.version}</project.build.finalName>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <maven.compiler.source>1.8</maven.compiler.source>
    <maven.compiler.target>1.8</maven.compiler.target>
</properties>

<build>
    <defaultGoal>clean package</defaultGoal>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <version>2.3.2</version>
            <configuration>
                <source>1.8</source>
                <target>1.8</target>
            </configuration>
        </plugin>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-surefire-plugin</artifactId>
            <version>2.15</version>
            <configuration>
                <argLine>-Dfile.encoding=UTF-8</argLine>
            </configuration>
        </plugin>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-shade-plugin</artifactId>
            <version>3.1.0</version>
            <executions>
                <execution>
                    <phase>package</phase>
                    <goals>
                        <goal>shade</goal>
                    </goals>
                </execution>
            </executions>
            <configuration>
                <shadedArtifactAttached>true</shadedArtifactAttached>
                <shadedClassifierName>shaded</shadedClassifierName>
                <transformers>
                    <transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
                        <mainClass>fr.misterassm.KamasBot</mainClass>
                    </transformer>
                </transformers>
            </configuration>
        </plugin>
        <plugin>
            <groupId>com.pyx4me</groupId>
            <artifactId>proguard-maven-plugin</artifactId>
            <version>2.0.4</version>
            <executions>
                <execution>
                    <phase>package</phase>
                    <goals>
                        <goal>proguard</goal>
                    </goals>
                </execution>
            </executions>
            <configuration>
                <proguardVersion>4.3</proguardVersion>
                <obfuscate>true</obfuscate>
                <injar>${project.build.finalName}-shaded.jar</injar>
                <outjar>${project.build.finalName}-small.jar</outjar>
                <proguardInclude>${basedir}/lib/config.pro</proguardInclude>
                <libs>
                    <lib>${java.home}/lib/rt.jar</lib>
                    <lib>${java.home}/lib/jsse.jar</lib>
                </libs>
            </configuration>
        </plugin>
    </plugins>
    <resources>
        <resource>
            <directory>${basedir}/src/main/resources</directory>
            <filtering>true</filtering>
            <includes>
                <include>*</include>
            </includes>
        </resource>
    </resources>
</build>

<dependencies>
    ...
    
    <!-- Guava -->
    <dependency>
        <groupId>com.google.guava</groupId>
        <artifactId>guava</artifactId>
        <version>30.0-jre</version>
    </dependency>
    <!-- Proguard -->
    <dependency>
        <groupId>net.sf.proguard</groupId>
        <artifactId>proguard-base</artifactId>
        <version>6.2.2</version>
    </dependency>
</dependencies>

【问题讨论】：

标签： java maven proguard proguard-maven-plugin

【解决方案1】：

(Unsupported version number [52.0] for class format)：这里指的是Java的类格式，这里是Java 1.8。

我看到您指定使用 proguard 版本 4.3，seems 已于 2008 年发布。这比 Java 1.8 发布早了六年。因此，Proguard 版本不支持这些类也就不足为奇了。

改变这一行：

<proguardVersion>4.3</proguardVersion>

截至撰写本文时，progaurd 的最新版本是 7.0.0。

【讨论】：