报错：Unsupported class file major version 59

运行Android studio平台版本3.6.3，sdk版本设置：

compileSdkVersion 30
buildToolsVersion '30.0.0'
defaultConfig {
    applicationId "com.linkkit.aiot_android_demo"
    minSdkVersion 19
    targetSdkVersion 29
    versionCode 2
    versionName "2.0.0"
    testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    multiDexEnabled true
}

JDK版本1.8

编译程序没有报错，运行时报错：Unsupported class file major version 59

Unsupported class file major version 59 

Unsupported class file major version 59

消除报错

你这个问题是因为你引用的一个包bouncycastle是jdk15的，你需要把他换成jdk8的或者，把你的jdk版本换成jdk15

Unsupported class file major version 59 android studio，这个问题是java的运行环境jre和工程的编译环境jdk不一致。比如说，jre7的环境去加载jdk8编译的class，所以导致错误。要么指定编译环境jdk，要么替换jre运行环境。其中version 59，是JDK 15版本。

java moudle library，指定java8, 直接在build.gradle文件中找个地方加入：

sourceCompatibility = 1.8
targetCompatibility = 1.8

报错：Unsupported class file major version 59
其原因就是版本不兼容问题

• 文章：illegalargumentexception: 'unsupported class file major version 57' 中也许有你想要的答案，请看下吧

补充新的编译错误如下所示：```xml
FAILURE: Build failed with an exception.

• What went wrong:
  Execution failed for task ':app:javaPreCompileDebug'.

  Could not resolve all files for configuration ':app:debugCompileClasspath'.
  Failed to transform artifact 'bcprov-jdk15on.jar (org.bouncycastle:bcprov-jdk15on:1.68)' to match attributes {artifactType=android-classes, org.gradle.libraryelements=jar, org.gradle.usage=java-runtime}.
  Execution failed for JetifyTransform: C:\Users\16966.gradle\caches\modules-2\files-2.1\org.bouncycastle\bcprov-jdk15on\1.68\46a080368d38b428d237a59458f9bc915222894d\bcprov-jdk15on-1.68.jar.
  Failed to transform 'C:\Users\16966.gradle\caches\modules-2\files-2.1\org.bouncycastle\bcprov-jdk15on\1.68\46a080368d38b428d237a59458f9bc915222894d\bcprov-jdk15on-1.68.jar' using Jetifier. Reason: Unsupported class file major version 59. (Run with --stacktrace for more details.)

• Try:
  Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.

• Get more help at https://help.gradle.org/

BUILD FAILED in 3s

```

把JDK的版本重新配置一下，或者在gradle文件中指定JDK版本，两种解决方案应该都可以解决这个问题