我有一个自己的框架，用于类任务(学校类，而不是 Java 类)，我将其放入 .jar 文件中，以便每当我对框架，我可以将它拖放到 Android Studio 中。在过去的 5 个左右的类任务中，一切都运行良好，现在突然间，在单击运行后解析我的 .jar 时，我遇到了 preDexDebug failed 错误。我在一个空白项目上对此进行了测试。项目一共有2个.jar:Gson，还有我自己的jar。它打印出 preDexDebug failed 在我拉入我自己的 .jar 之后...我已经为此苦苦挣扎了两个小时，我不知道我在做什么完全可以解决这个问题...

我尝试过重建、清理、检查 gradle.build 是否重复、多次复制项目以及多次编译和复制 .jar .

带有 64 位 Oracle JDK 1.8.0_31 的 Ubuntu x64。使用与 JDK bundle 在一起的 Java

Android Studio 输出:

Configuration on demand is an incubating feature.
:app:preBuild UP-TO-DATE
:app:preDebugBuild UP-TO-DATE
:app:compileDebugNdk UP-TO-DATE
:app:checkDebugManifest
:app:preReleaseBuild UP-TO-DATE
:app:prepareComAndroidSupportAppcompatV72103Library UP-TO-DATE
:app:prepareComAndroidSupportSupportV42103Library UP-TO-DATE
:app:prepareDebugDependencies
:app:compileDebugAidl UP-TO-DATE
:app:compileDebugRenderscript UP-TO-DATE
:app:generateDebugBuildConfig UP-TO-DATE
:app:generateDebugAssets UP-TO-DATE
:app:mergeDebugAssets UP-TO-DATE
:app:generateDebugResValues UP-TO-DATE
:app:generateDebugResources UP-TO-DATE
:app:mergeDebugResources UP-TO-DATE
:app:processDebugManifest UP-TO-DATE
:app:processDebugResources UP-TO-DATE
:app:generateDebugSources UP-TO-DATE
:app:compileDebugJava
:app:preDexDebug
AGPBI: {"kind":"SIMPLE","text":"UNEXPECTED TOP-LEVEL EXCEPTION:","position":{},"original":"UNEXPECTED TOP-LEVEL EXCEPTION:"}
AGPBI: {"kind":"SIMPLE","text":"com.android.dx.cf.iface.ParseException: bad class file magic (cafebabe) or version (0034.0000)","position":{},"original":"com.android.dx.cf.iface.ParseException: bad class file magic (cafebabe) or version (0034.0000)"}
AGPBI: {"kind":"SIMPLE","text":"\tat com.android.dx.cf.direct.DirectClassFile.parse0(DirectClassFile.java:472)","position":{},"original":"\tat com.android.dx.cf.direct.DirectClassFile.parse0(DirectClassFile.java:472)"}
AGPBI: {"kind":"SIMPLE","text":"\tat com.android.dx.cf.direct.DirectClassFile.parse(DirectClassFile.java:406)","position":{},"original":"\tat com.android.dx.cf.direct.DirectClassFile.parse(DirectClassFile.java:406)"}
AGPBI: {"kind":"SIMPLE","text":"\tat com.android.dx.cf.direct.DirectClassFile.parseToInterfacesIfNecessary(DirectClassFile.java:388)","position":{},"original":"\tat com.android.dx.cf.direct.DirectClassFile.parseToInterfacesIfNecessary(DirectClassFile.java:388)"}
AGPBI: {"kind":"SIMPLE","text":"\tat com.android.dx.cf.direct.DirectClassFile.getMagic(DirectClassFile.java:251)","position":{},"original":"\tat com.android.dx.cf.direct.DirectClassFile.getMagic(DirectClassFile.java:251)"}
AGPBI: {"kind":"SIMPLE","text":"\tat com.android.dx.command.dexer.Main.processClass(Main.java:704)","position":{},"original":"\tat com.android.dx.command.dexer.Main.processClass(Main.java:704)"}
AGPBI: {"kind":"SIMPLE","text":"\tat com.android.dx.command.dexer.Main.processFileBytes(Main.java:673)","position":{},"original":"\tat com.android.dx.command.dexer.Main.processFileBytes(Main.java:673)"}
AGPBI: {"kind":"SIMPLE","text":"\tat com.android.dx.command.dexer.Main.access$300(Main.java:83)","position":{},"original":"\tat com.android.dx.command.dexer.Main.access$300(Main.java:83)"}
AGPBI: {"kind":"SIMPLE","text":"\tat com.android.dx.command.dexer.Main$1.processFileBytes(Main.java:602)","position":{},"original":"\tat com.android.dx.command.dexer.Main$1.processFileBytes(Main.java:602)"}
AGPBI: {"kind":"SIMPLE","text":"\tat com.android.dx.cf.direct.ClassPathOpener.processArchive(ClassPathOpener.java:284)","position":{},"original":"\tat com.android.dx.cf.direct.ClassPathOpener.processArchive(ClassPathOpener.java:284)"}
AGPBI: {"kind":"SIMPLE","text":"\tat com.android.dx.cf.direct.ClassPathOpener.processOne(ClassPathOpener.java:166)","position":{},"original":"\tat com.android.dx.cf.direct.ClassPathOpener.processOne(ClassPathOpener.java:166)"}
AGPBI: {"kind":"SIMPLE","text":"\tat com.android.dx.cf.direct.ClassPathOpener.process(ClassPathOpener.java:144)","position":{},"original":"\tat com.android.dx.cf.direct.ClassPathOpener.process(ClassPathOpener.java:144)"}
AGPBI: {"kind":"SIMPLE","text":"\tat com.android.dx.command.dexer.Main.processOne(Main.java:632)","position":{},"original":"\tat com.android.dx.command.dexer.Main.processOne(Main.java:632)"}
AGPBI: {"kind":"SIMPLE","text":"\tat com.android.dx.command.dexer.Main.processAllFiles(Main.java:510)","position":{},"original":"\tat com.android.dx.command.dexer.Main.processAllFiles(Main.java:510)"}
AGPBI: {"kind":"SIMPLE","text":"\tat com.android.dx.command.dexer.Main.runMonoDex(Main.java:280)","position":{},"original":"\tat com.android.dx.command.dexer.Main.runMonoDex(Main.java:280)"}
AGPBI: {"kind":"SIMPLE","text":"\tat com.android.dx.command.dexer.Main.run(Main.java:246)","position":{},"original":"\tat com.android.dx.command.dexer.Main.run(Main.java:246)"}
AGPBI: {"kind":"SIMPLE","text":"\tat com.android.dx.command.dexer.Main.main(Main.java:215)","position":{},"original":"\tat com.android.dx.command.dexer.Main.main(Main.java:215)"}
AGPBI: {"kind":"SIMPLE","text":"\tat com.android.dx.command.Main.main(Main.java:106)","position":{},"original":"\tat com.android.dx.command.Main.main(Main.java:106)"}
AGPBI: {"kind":"SIMPLE","text":"...while parsing reactor/communications/ClientEndpointTCP.class","position":{},"original":"...while parsing reactor/communications/ClientEndpointTCP.class"}
AGPBI: {"kind":"SIMPLE","text":"1 error; aborting","position":{},"original":"1 error; aborting"}

最佳答案

原来 Java 8 还不受 Android SDK 的支持(或类似的东西)。在我的桌面上安装 Oracle JDK 7，并重新编译我的 .jar 完全解决了这个问题。

最重要的部分是产生的错误的第二行:“错误的类文件 magic (cafebabe) 或版本 (0034.0000)”。 0x34 是 52 的十六进制，这意味着二进制文件针对支持 Java 8 的 JRE，但 Android Studio 的系统要求声明需要 JDK 7

切换到 Oracle JDK 7 的步骤:

1. 从 Oracle 的站点下载 JDK .tar
2. 将内容解压到/opt/
3. sudo update-alternatives --install/bin/java java/opt/jdk*version*/jre/bin/java 1023
4. sudo update-alternatives --install/bin/javac javac/opt/jdk*version*/bin/javac 1023
5. sudo update-alternatives --install/bin/jar jar/opt/jdk*version*/bin/jar 1023

https://askubuntu.com/questions/56104/how-can-i-install-sun-oracles-proprietary-java-jdk-6-7-8-or-jre

关于java - 添加 jar 文件后的 Android Studio preDexDebug，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/28653135/