在 Android Maven 项目中使用纯 Java 库

Question

我有一个使用纯 Java 库的 Android Maven 项目，在过去的几天里，我已经为此苦苦挣扎了几个小时，无论我做什么，我都会不断收到以下错误：

[INFO] d:\Development-Android\SDKs\Android\platform-tools\aapt.exe [package, -f, -M, D:\Development-Android\Workspaces\Android-Workspace\S-O-D\AndroidManifest.xml, -S, D:\Development-Android\Workspaces\Android-Workspace\S-O-D\res, --auto-add-overlay, -A, D:\Development-Android\Workspaces\Android-Workspace\S-O-D\target\generated-sources\combined-assets\assets, -I, d:\Development-Android\SDKs\Android\platforms\android-7\android.jar, -F, D:\Development-Android\Workspaces\Android-Workspace\S-O-D\target\s-o-d-1.0.0.ap_]
[ERROR] Cannot add source folder
com.android.sdklib.build.DuplicateFileException: Duplicate files at the same path inside the APK
    at com.android.sdklib.build.ApkBuilder.doAddFile(ApkBuilder.java:716)
    at com.android.sdklib.build.ApkBuilder.processFileForResource(ApkBuilder.java:762)
    at com.android.sdklib.build.ApkBuilder.addSourceFolder(ApkBuilder.java:587)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    at com.jayway.maven.plugins.android.phase09package.ApkBuilder.addSourceFolder(ApkBuilder.java:244)
    at com.jayway.maven.plugins.android.phase09package.ApkMojo.doAPKWithAPKBuilder(ApkMojo.java:341)
    at com.jayway.maven.plugins.android.phase09package.ApkMojo.createApkFile(ApkMojo.java:249)
    at com.jayway.maven.plugins.android.phase09package.ApkMojo.execute(ApkMojo.java:207)
    at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:107)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:209)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:153)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:145)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:84)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:59)
    at org.apache.maven.lifecycle.internal.LifecycleStarter.singleThreadedBuild(LifecycleStarter.java:183)
    at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:161)
    at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:319)
    at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:156)
    at org.apache.maven.cli.MavenCli.execute(MavenCli.java:534)
    at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:196)
    at org.apache.maven.cli.MavenCli.main(MavenCli.java:141)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:290)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:230)
    at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:409)
    at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:352)

经过长时间的尝试，我能够理解所指的重复项是输出目录中的重复文件，Android android-classes 文件夹之一，以及 maven 输出 classes 文件夹。

所以在我继续之前，我已经尝试找出（但我无法找到答案）Android Maven 插件是否支持导入纯 Java jar？

嗬，是的，非常重要，进行全新安装，而不仅仅是安装！！！

提前致谢，

亚当·泽哈维。

Answer 1

这可能会有所帮助：

https://groups.google.com/forum/#!topic/maven-android-developers/QjbzoaC1Q3k

Answer 2

好吧，我花了很长时间才完全理解这个错误以解决它，并且还启用了从 Eclipse 快捷方式进行调试。

所以这里没有任何保证是一个通用的解决方案，到目前为止它对我来说非常有效，到目前为止我没有遇到任何问题：

我有一个父 pom：

<?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.nu.art.software.android</groupId>
    <artifactId>android-maven-parent</artifactId>
    <version>1.0.0</version>
    <packaging>pom</packaging>

    <name>android-maven-parent</name>
    <url>http://maven.apache.org</url>

    <properties>
        <android.sdk>7</android.sdk>
        <android.emulator.name>emulator1</android.emulator.name>
        <android.version>2.1_r1</android.version>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>

    <dependencies>
        <dependency>
            <groupId>com.google.android</groupId>
            <artifactId>android</artifactId>
            <version>${android.version}</version>
            <type>jar</type>
            <scope>provided</scope>
        </dependency>
    </dependencies>

    <build>
        <sourceDirectory>src</sourceDirectory>
        <outputDirectory>./target/android-classes</outputDirectory>
        <plugins>
            <plugin>
                <groupId>com.jayway.maven.plugins.android.generation2</groupId>
                <artifactId>maven-android-plugin</artifactId>
                <version>3.0.0-alpha-2</version>
                <configuration>
                    <sdk>
                        <platform>${android.sdk}</platform>
                    </sdk>
                    <emulator>
                        <avd>${android.emulator.name}</avd>
                    </emulator>
                    <deleteConflictingFiles>true</deleteConflictingFiles>
                    <undeployBeforeDeploy>true</undeployBeforeDeploy>
                </configuration>
                <extensions>true</extensions>
            </plugin>
            <plugin>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>2.3.2</version>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-dependency-plugin</artifactId>
                <version>2.3</version>
                <executions>
                    <execution>
                        <id>unpack</id>
                        <phase>generate-sources</phase>
                        <goals>
                            <goal>unpack-dependencies</goal>
                        </goals>
                        <configuration>
                            <excludeScope>provided</excludeScope>
                            <skip>true</skip>
                            <includes>**/*.class</includes>
                            <outputDirectory>${project.basedir}/bin</outputDirectory>
                            <overWriteReleases>true</overWriteReleases>
                            <overWriteSnapshots>true</overWriteSnapshots>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-antrun-plugin</artifactId>
                <version>1.3</version>
                <executions>
                    <execution>
                        <id>Make-classes-output</id>
                        <phase>clean</phase>
                        <goals>
                            <goal>run</goal>
                        </goals>
                        <inherited>true</inherited>
                        <configuration>
                            <tasks>
                                <echo>Creating '${project.basedir}/target/classes' Directory</echo>
                                <mkdir
                                    dir="${project.basedir}/target/classes" />
                            </tasks>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>
</project>

插件中缺少的所有逻辑都支持从 Eclipse 启动和调试，另外还解决了我的重复问题。 （我第一次有 res 文件夹，作为源文件夹，这搞砸了，后来它在依赖项中重复了）

接下来每个最终项目当然都有自己的 pom，这可以将依赖项复制到 Eclipse 输出文件夹：

<?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">
    <parent>
        <artifactId>android-maven-parent</artifactId>
        <groupId>com.nu.art.software.android</groupId>
        <version>1.0.0</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.nu.art.software.sod</groupId>
    <artifactId>s-o-d</artifactId>
    <version>1.0.0</version>
    <packaging>apk</packaging>
    <name>S-O-D</name>
    <dependencies>
        <dependency>
            <groupId>com.nu.art.software</groupId>
            <artifactId>rexml</artifactId>
            <version>0.0.1</version>
            <type>jar</type>
            <scope>compile</scope>
        </dependency>
        <dependency>
            <groupId>com.nu.art.software</groupId>
            <artifactId>nu-art-module-manager</artifactId>
            <version>0.0.1</version>
            <type>jar</type>
            <scope>compile</scope>
        </dependency>
        <dependency>
            <groupId>com.nu.art.software</groupId>
            <artifactId>nu-art-generator</artifactId>
            <version>0.0.1</version>
            <type>jar</type>
            <scope>compile</scope>
        </dependency>
        <dependency>
            <groupId>com.nu.art.software</groupId>
            <artifactId>nu-art-reflection</artifactId>
            <version>0.0.1</version>
            <type>jar</type>
            <scope>compile</scope>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-dependency-plugin</artifactId>
                <version>2.3</version>
                <executions>
                    <execution>
                        <id>unpack</id>
                        <configuration>
                            <skip>false</skip>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>
</project>

最后的话，在安装最终项目时，此技巧将所有依赖项提取到 Eclipse 输出文件夹中，该文件夹定义为“./bin”（默认 ADT 插件输出文件夹，如果我不是错误）。 之后，Eclipse 使用数据构建 APK，它的输出文件夹中有 wallah，你有和 apk，F11 可以用它来启动调试器。

这又对我有用……我希望这对你也有帮助。

分享你的想法... 亚当。

Answer 3

里卡多的链接很好。

添加

<extractDuplicates>true</extractDuplicates>

到 Maven 插件的配置将确保 Jars 中的重复文件不会导致 aapt 崩溃。否则，包含与根包中类似名称的许可证文件一样的文件的多个 jar 是一个问题（例如 jackson-2.2.0）