I have read this, It looks like its a known issue from quite some time. But i was not receiving any warning or crash when i was not using pro-guard. After enabling it, I am receiving around 500 warnings like following;
Warning:com.loopj.android.http.AsyncHttpClient: can't find referenced class cz.msebera.android.httpclient
I have tried following, but still all of the warnings are there.
android {
compileSdkVersion 24
buildToolsVersion "24.0.3"
useLibrary 'org.apache.http.legacy'
}
I am not using http-client library, but there may be some other library that I am using in my project is using this.
Warnings
Warning:com.loopj.android.http.RangeFileAsyncHttpResponseHandler: can't find referenced class cz.msebera.android.httpclient.HttpResponse
Warning:com.loopj.android.http.RangeFileAsyncHttpResponseHandler: can't find referenced class cz.msebera.android.httpclient.Header
Warning:com.loopj.android.http.RangeFileAsyncHttpResponseHandler: can't find referenced class cz.msebera.android.httpclient.StatusLine
Warning:com.loopj.android.http.RangeFileAsyncHttpResponseHandler: can't find referenced class cz.msebera.android.httpclient.HttpResponse
Warning:com.loopj.android.http.RangeFileAsyncHttpResponseHandler: can't find referenced class cz.msebera.android.httpclient.HttpEntity
Warning:com.loopj.android.http.RangeFileAsyncHttpResponseHandler: can't find referenced class cz.msebera.android.httpclient.client.methods.HttpUriRequest
Warning:com.loopj.android.http.RequestParams: can't find referenced class cz.msebera.android.httpclient.protocol.HTTP
Warning:com.loopj.android.http.RequestParams: can't find referenced class cz.msebera.android.httpclient.message.BasicNameValuePair
Warning:com.loopj.android.http.RequestParams: can't find referenced class cz.msebera.android.httpclient.client.entity.UrlEncodedFormEntity
Warning:com.loopj.android.http.RequestParams: can't find referenced class cz.msebera.android.httpclient.message.BasicNameValuePair
Warning:com.loopj.android.http.RequestParams: can't find referenced class cz.msebera.android.httpclient.client.utils.URLEncodedUtils
Warning:com.loopj.android.http.RequestParams: can't find referenced class cz.msebera.android.httpclient.message.BasicNameValuePair
Warning:com.loopj.android.http.RequestParams: can't find referenced class cz.msebera.android.httpclient.client.utils.URLEncodedUtils
Warning:com.loopj.android.http.RequestParams: can't find referenced class cz.msebera.android.httpclient.message.BasicNameValuePair
Warning:com.loopj.android.http.RequestParams: can't find referenced class cz.msebera.android.httpclient.HttpEntity
Warning:com.loopj.android.http.RequestParams: can't find referenced class cz.msebera.android.httpclient.message.BasicNameValuePair
Warning:rx.internal.util.unsafe.BaseLinkedQueueConsumerNodeRef: can't find referenced class sun.misc.Unsafe
Warning:rx.internal.util.unsafe.BaseLinkedQueueProducerNodeRef: can't find referenced class sun.misc.Unsafe
Warning:rx.internal.util.unsafe.ConcurrentCircularArrayQueue: can't find referenced class sun.misc.Unsafe
Warning:rx.internal.util.unsafe.ConcurrentSequencedCircularArrayQueue: can't find referenced class sun.misc.Unsafe
Warning:rx.internal.util.unsafe.MpmcArrayQueueConsumerField: can't find referenced class sun.misc.Unsafe
Warning:rx.internal.util.unsafe.MpmcArrayQueueProducerField: can't find referenced class sun.misc.Unsafe
Warning:rx.internal.util.unsafe.MpscLinkedQueue: can't find referenced class sun.misc.Unsafe
Warning:rx.internal.util.unsafe.SpmcArrayQueueConsumerField: can't find referenced class sun.misc.Unsafe
Warning:rx.internal.util.unsafe.SpmcArrayQueueProducerField: can't find referenced class sun.misc.Unsafe
Warning:rx.internal.util.unsafe.SpscArrayQueue: can't find referenced class sun.misc.Unsafe
Warning:rx.internal.util.unsafe.SpscArrayQueueConsumerField: can't find referenced class sun.misc.Unsafe
Warning:rx.internal.util.unsafe.SpscArrayQueueProducerFields: can't find referenced class sun.misc.Unsafe
Warning:rx.internal.util.unsafe.UnsafeAccess: can't find referenced class sun.misc.Unsafe
Warning:library class android.webkit.WebView depends on program class android.net.http.SslCertificate
Warning:library class android.webkit.WebViewClient depends on program class android.net.http.SslError
Warning:library class org.apache.http.conn.ssl.SSLSocketFactory depends on program class org.apache.http.conn.scheme.HostNameResolver
Warning:library class org.apache.http.conn.ssl.SSLSocketFactory depends on program class org.apache.http.params.HttpParams
Warning:library class org.apache.http.params.HttpConnectionParams depends on program class org.apache.http.params.HttpParams
Warning:there were 757 unresolved references to classes or interfaces.
Warning:there were 18 instances of library classes depending on program classes.
Warning:there were 8 unresolved references to program class members.
Warning:there were 2 unresolved references to library class members.
After adding the lines provided in Hitesh Gehlot answer. I am receiving these 5 warnings.
Information:Gradle tasks [:app:assembleRelease]
Warning:com.algolia.search.saas.APIClient: can't find referenced method 'org.json.JSONObject put(java.lang.String,java.util.Collection)' in library class org.json.JSONObject
Warning:com.algolia.search.saas.Index: can't find referenced method 'org.json.JSONObject put(java.lang.String,java.util.Collection)' in library class org.json.JSONObject
Warning:library class android.webkit.WebView depends on program class android.net.http.SslCertificate
Warning:library class android.webkit.WebViewClient depends on program class android.net.http.SslError
Warning:there were 3 instances of library classes depending on program classes.
Warning:there were 2 unresolved references to library class members.
Warning:Exception while processing task java.io.IOException: Please correct the above warnings first.
Error:Execution failed for task ':app:transformClassesAndResourcesWithProguardForRelease'.
> java.io.IOException: Please correct the above warnings first.
