周六整整一天就被这个奇葩问题困扰了，整整一天闷闷不乐心情烦躁，中午没有照常吃饭没有给狗洗澡晚上就点了个外卖也不跑步遛狗。最后第二天周日终于解决，瞬间突然觉得自己萌萌哒~~~~
首先先让我们看看开头的一个问题
如果只想关注答案的，直接看结尾，但是因为导致这个问题的有很多种，所以建议还是全程看
Cause: Dex cannot parse version 52 byte code.
This is caused by library dependencies that have been compiled using Java 8 or above.
If you are using the 'java' gradle plugin in a library submodule add
targetCompatibility = '1.7'
sourceCompatibility = '1.7'
to that submodule's build.gradle file.
那么前面最热门的答案都是：
添加这些配置即可
defaultConfig {
jackOptions {
enabled true
}
}
dexOptions {
}
compileOptions {
sourceCompatibility JavaVersion.VERSION_1_8
targetCompatibility JavaVersion.VERSION_1_8
}
或者这个配置
classpath 'com.android.tools.build:gradle:3.0.0'
and
android {
compileSdkVersion 26
buildToolsVersion "26.0.1"
defaultConfig {
...
//jackOptions { // DEPRECATED
//enabled true
//}
}
dexOptions {
incremental true
}
compileOptions {
sourceCompatibility JavaVersion.VERSION_1_8
targetCompatibility JavaVersion.VERSION_1_8
}
}
运行，报错
Cannot get property 'destinationDir' on null object
又google了一番
如果使用enabled true开启了1.8
注：AS2.1以上时，app的build.gradle里不要加
apply plugin: 'me.tatarka.retrolambda'
好吧好吧，我删掉~
终于可以运行，谁知道……
运行到某个地方，又报错
IncompatibleClassChangeError …
was expected to be of type direct but instead was found to be of type virtual
于是又google
I see you are building for android, so maybe issue is as follows: build set minSdkVersion 21 - android 5 lollipop AND targetCompatibility for java 8 - which is supported (very limited though) starting from sdk 24, thus causing your build problems. You can address this issue three ways:
1) build for minSdkVersion 24, targeting solid [0.4%](https://developer.android.com/about/dashboards/index.html) of devices
2) get rid of java 8 features and set source/target compatibility to java 7
3) use java 8 features and build using [retrolambda](https://github.com/orfjackal/retrolambda) (with some limitations, present on lib readme)
大致意思还是java8和兼容java7的问题！
那我就纳闷了，我把我以前的项目跟这个项目重新对比，用排除法将配置一个一个的修改复原，终于找到一个问题……
总结
是下面这个包引起的！！！
compile 'org.jetbrains:annotations:15.0'
还是回到这个热门答案
https://stackoverflow.com/questions/37020413/android-dex-cannot-parse-version-52-byte-code
有一个稍微冷门答案提及到
If you use org.jetbrains:annotation:15 and retrolambda plugin then remove line compile org.jetbrains:annotations:15.0 from your build.gradle and the error will disappear. It works for me.
大致意思是如果你使用org.jetbrains:annotation:15包和retrolambda插件，那么删掉org.jetbrains:annotation:15包就可以了…………应该是冲突造成原因了
有时候就是莫名其妙的问题耽搁事件，我的整整一天假期就这么没了。祝大家周末愉快
