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javaandroidandroid-multidex

MultiDex cause java.lang.NoClassDefFoundError in Android 4.4

I want to import Mina sshd to my android application.

implementation group: 'org.apache.sshd', name: 'sshd-core', version: '2.1.0'

But,at Runtime,this line

public static final Factory<SshServer> DEFAULT_SSH_SERVER_FACTORY = SshServer::new;

throw exception

> java.lang.NoClassDefFoundError: 
org.apache.sshd.server.-$$Lambda$xH0wWyo4NWY-u4MuNlGAr_IPDQc
        at org.apache.sshd.server.SshServer.<clinit>(SshServer.java:88)
        at com.ymz.myapplication.MainActivity$startSshd$1.run(MainActivity.kt:25)
        at java.lang.Thread.run(Thread.java:841)

At frist,I check the class.dex enter image description here

The class which not definde is exist。

my gradle 

    apply plugin: 'com.android.application'

    apply plugin: 'kotlin-android'

    apply plugin: 'kotlin-android-extensions'

    android {
        compileSdkVersion 28
        defaultConfig {
            applicationId "com.ymz.myapplication"
            minSdkVersion 19
            targetSdkVersion 28
            multiDexEnabled true
            versionCode 1
            versionName "1.0"
            multiDexKeepProguard file('multidex-config.pro')
    //        multiDexKeepFile file('multidex-config.txt')
            testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
        }

        buildTypes {
            release {
                minifyEnabled false
                proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
            }
        }
                                ....
    }

Already add File multidex-config.pro:

-keep class org.apache.sshd.** { *; }

Solution

  • Try adding the following rules in your proguard file:-

    SSHd requires mina, and mina uses reflection so some classes would get deleted

        -keep class org.apache.mina.** {*;}
    -keep class org.apache.sshd.** {*;}

   -dontwarn org.apache.sshd.**
   -dontwarn org.apache.mina.**

    Also check your gradle file for these two dependencies:-

    implementation 'org.apache.sshd:sshd-core:0.14.0'
implementation 'org.apache.mina:mina-core:2.0.19'