"Execution failed for task: ':app:javaPreCompileDebug' " in Android Studio 3.0.1

Question

I get the following errors when trying to execute my project:

Error:Execution failed for task ':app:javaPreCompileDebug'.

Annotation processors must be explicitly declared now. The following dependencies on the compile classpath are found to contain annotation processor. Please add them to the annotationProcessor configuration. - butterknife-7.0.1.jar (com.jakewharton:butterknife:7.0.1) Alternatively, set android.defaultConfig.javaCompileOptions.annotationProcessorOptions.includeCompileClasspath = true to continue with previous behavior. Note that this option is deprecated and will be removed in the future. See https://developer.android.com/r/tools/annotation-processor-error-message.html for more details.

Please don't mark this question as duplicate as other question regrading this, here, is for lombok, which I'm not using.

Solution 1

As the error says, you need to use annotationProcessor in your app build.gradle. Afaik, you need to upgrade the ButterKnife library to version 8.8.1. You need to use something like this:

dependencies {
  compile 'com.jakewharton:butterknife:8.8.1'
  annotationProcessor 'com.jakewharton:butterknife-compiler:8.8.1'
}

Please check Android studio 3.0 butterknife error issue for the details.

Solution 2

Adding these two line in app/build.gradle 

dependencies {
  compile 'com.jakewharton:butterknife:8.8.1'
  annotationProcessor 'com.jakewharton:butterknife-compiler:8.8.1'
}


It worked for me