What is error? and how to solve [closed]

08-20 18:42:28.284 8769-8769/com.wordpress.prathamesh99wordpress.www.wifiset E/AndroidRuntime: FATAL EXCEPTION: main Process: com.wordpress.prathamesh99wordpress.www.wifiset, PID: 8769 java.lang.RuntimeException: Unable to instantiate application com.android.tools.fd.runtime.BootstrapApplication: java.lang.ClassNotFoundException: Didn't find class "com.android.tools.fd.runtime.BootstrapApplication" on path: DexPathList[[zip file "/data/app/com.wordpress.prathamesh99wordpress.www.wifiset-1/base.apk"],nativeLibraryDirectories=[/data/app/com.wordpress.prathamesh99wordpress.www.wifiset-1/lib/arm, /vendor/lib, /system/lib]] at android.app.LoadedApk.makeApplication(LoadedApk.java:680) at android.app.ActivityThread.handleBindApplication(ActivityThread.java:6395) at android.app.ActivityThread.access$1800(ActivityThread.java:229) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1887) at android.os.Handler.dispatchMessage(Handler.java:102) at android.os.Looper.loop(Looper.java:148) at android.app.ActivityThread.main(ActivityThread.java:7325) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120) Caused by: java.lang.ClassNotFoundException: Didn't find class "com.android.tools.fd.runtime.BootstrapApplication" on path: DexPathList[[zip file "/data/app/com.wordpress.prathamesh99wordpress.www.wifiset-1/base.apk"],nativeLibraryDirectories=[/data/app/com.wordpress.prathamesh99wordpress.www.wifiset-1/lib/arm, /vendor/lib, /system/lib]] at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:56) at java.lang.ClassLoader.loadClass(ClassLoader.java:511) at java.lang.ClassLoader.loadClass(ClassLoader.java:469) at android.app.Instrumentation.newApplication(Instrumentation.java:1005) at android.app.LoadedApk.makeApplication(LoadedApk.java:670) at android.app.ActivityThread.handleBindApplication(ActivityThread.java:6395)  at android.app.ActivityThread.access$1800(ActivityThread.java:229)  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1887)  at android.os.Handler.dispatchMessage(Handler.java:102)  at android.os.Looper.loop(Looper.java:148)  at android.app.ActivityThread.main(ActivityThread.java:7325)  at java.lang.reflect.Method.invoke(Native Method)  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230)  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120)  Suppressed: java.io.IOException: No original dex files found for dex location (arm) /data/app/com.wordpress.prathamesh99wordpress.www.wifiset-1/base.apk () at dalvik.system.DexFile.openDexFileNative(Native Method) at dalvik.system.DexFile.openDexFile(DexFile.java:295) at dalvik.system.DexFile.(DexFile.java:80) at dalvik.system.DexFile.(DexFile.java:59) at dalvik.system.DexPathList.loadDexFile(DexPathList.java:279) at dalvik.system.DexPathList.makePathElements(DexPathList.java:248) at dalvik.system.DexPathList.(DexPathList.java:120) at dalvik.system.BaseDexClassLoader.(BaseDexClassLoader.java:48) at dalvik.system.PathClassLoader.(PathClassLoader.java:65) at android.app.ApplicationLoaders.getClassLoader(ApplicationLoaders.java:86) at android.app.ApplicationLoaders.getClassLoader(ApplicationLoaders.java:47) at android.app.LoadedApk.getClassLoader(LoadedApk.java:438) at android.app.LoadedApk.makeApplication(LoadedApk.java:663) ... 9 more Suppressed: java.lang.ClassNotFoundException: com.android.tools.fd.runtime.BootstrapApplication at java.lang.Class.classForName(Native Method) at java.lang.BootClassLoader.findClass(ClassLoader.java:781) at java.lang.BootClassLoader.loadClass(ClassLoader.java:841) at java.lang.ClassLoader.loadClass(ClassLoader.java:504) ... 12 more Caused by: java.lang.NoClassDefFoundError: Class not found using the boot class loader; no stack trace available