unsupported class file version 53.0

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 记录一个Java 编译版本引发的报错，项目中使用的 jdk 8 编译，而依赖的 jar 包默认使用 java9 编译。

报错日志：

Caused by: com.android.builder.dexing.DexArchiveBuilderException: Failed to process /Users/jacinth/.gradle/caches/modules-2/files-2.1/org.bouncycastle/bcprov-jdk15on/1.62/633b6739ef8f07f2e71f8eebd1c6f25b17a4ec7d/bcprov-jdk15on-1.62.jar
	at com.android.build.gradle.internal.transforms.DexArchiveBuilderTransform.launchProcessing(DexArchiveBuilderTransform.java:550)
	at com.android.build.gradle.internal.transforms.DexArchiveBuilderTransform.lambda$convertToDexArchive$1(DexArchiveBuilderTransform.java:488)
	at java.util.concurrent.ForkJoinTask$AdaptedCallable.exec(ForkJoinTask.java:1424)
	at java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:289)
	at java.util.concurrent.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1056)
	at java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1692)
	at java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:157)
Caused by: com.android.builder.dexing.DexArchiveBuilderException: Error while dexing META-INF/versions/9/module-info.class

	at com.android.builder.dexing.DxDexArchiveBuilder.getExceptionToRethrow(DxDexArchiveBuilder.java:143)
	at com.android.builder.dexing.DxDexArchiveBuilder.convert(DxDexArchiveBuilder.java:89)
	at com.android.build.gradle.internal.transforms.DexArchiveBuilderTransform.launchProcessing(DexArchiveBuilderTransform.java:545)
	... 6 more
Caused by: com.android.dx.cf.iface.ParseException: unsupported class file version 53.0
	at com.android.dx.cf.direct.DirectClassFile.parse0(DirectClassFile.java:499)
	at com.android.dx.cf.direct.DirectClassFile.parse(DirectClassFile.java:420)
	at com.android.dx.cf.direct.DirectClassFile.parseToInterfacesIfNecessary(DirectClassFile.java:402)
	at com.android.dx.cf.direct.DirectClassFile.getMagic(DirectClassFile.java:253)
	at com.android.builder.dexing.DxDexArchiveBuilder.dex(DxDexArchiveBuilder.java:99)
	at com.android.builder.dexing.DxDexArchiveBuilder.convert(DxDexArchiveBuilder.java:86)
	... 7 more

原因：

引入的 jar 包的编译版本比 android studio 使用的 jdk 版本要高，导致 jar 包编译报错。

解决：

（1）使用更高版本的 jdk（推荐）

（2）删除 module-info.class 文件。（这个方法应该不是对每个人都有效，报错日志里明确指出了该文件报错，可以使用 WinRAR 打开 jar 包，进入对应的目录删除报错的文件，再重新在项目中依赖，如果编译不报错就可行）

附一份 java 版本号对应表

Java SE 9 = 53,

Java SE 8 = 52,

Java SE 7 = 51,

Java SE 6.0 = 50,

Java SE 5.0 = 49,

JDK 1.4 = 48,

JDK 1.3 = 47,

JDK 1.2 = 46,

JDK 1.1 = 45

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