Develop Reference

use room ORM testing with minify and proguard

I am using room ORM in my project every things good but when i test project with minify minifyEnabled true i face to this error i tried many but did not work. and the following warnings:
Information:Gradle tasks [:app:assembleDebug, :app:assembleDebugAndroidTest]
Warning:org.hamcrest.integration.EasyMock2Adapter: can't find superclass or interface org.easymock.IArgumentMatcher
Warning:org.hamcrest.integration.JMock1Adapter: can't find superclass or interface org.jmock.core.Constraint
Warning:library class android.test.AndroidTestCase extends or implements program class junit.framework.TestCase
Warning:library class android.test.AndroidTestRunner extends or implements program class junit.runner.BaseTestRunner
Warning:library class android.test.InstrumentationTestCase extends or implements program class junit.framework.TestCase
Warning:library class android.test.InstrumentationTestSuite extends or implements program class junit.framework.TestSuite
Warning:library class android.test.suitebuilder.TestSuiteBuilder$FailedToCreateTests extends or implements program class junit.framework.TestCase
Warning:android.support.test.espresso.core.deps.guava.cache.Striped64: can't find referenced class sun.misc.Unsafe
Warning:android.support.test.espresso.core.deps.guava.cache.Striped64$1: can't find referenced class sun.misc.Unsafe
Warning:android.support.test.espresso.core.deps.guava.cache.Striped64$Cell: can't find referenced class sun.misc.Unsafe
Warning:android.support.test.espresso.core.deps.guava.primitives.UnsignedBytes$LexicographicalComparatorHolder$UnsafeComparator: can't find referenced class sun.misc.Unsafe
Warning:android.support.test.espresso.core.deps.guava.primitives.UnsignedBytes$LexicographicalComparatorHolder$UnsafeComparator$1: can't find referenced class sun.misc.Unsafe
Warning:android.support.test.runner.MonitoringInstrumentation: can't find referenced method 'android.app.Instrumentation$ActivityResult execStartActivity(android.content.Context,android.os.IBinder,android.os.IBinder,android.app.Activity,android.content.Intent,int)' in program class android.support.test.internal.runner.hidden.ExposedInstrumentationApi
Warning:android.support.test.runner.MonitoringInstrumentation: can't find referenced method 'android.app.Instrumentation$ActivityResult execStartActivity(android.content.Context,android.os.IBinder,android.os.IBinder,android.app.Activity,android.content.Intent,int,android.os.Bundle)' in program class android.support.test.internal.runner.hidden.ExposedInstrumentationApi
Warning:android.support.test.runner.MonitoringInstrumentation: can't find referenced method 'android.app.Instrumentation$ActivityResult execStartActivity(android.content.Context,android.os.IBinder,android.os.IBinder,android.app.Fragment,android.content.Intent,int,android.os.Bundle)' in program class android.support.test.internal.runner.hidden.ExposedInstrumentationApi
Warning:com.squareup.javawriter.JavaWriter: can't find referenced class javax.lang.model.element.Modifier
Warning:org.hamcrest.JMock1Matchers: can't find referenced class org.jmock.core.Constraint
Warning:org.hamcrest.beans.HasPropertyWithValue: can't find referenced class java.beans.PropertyDescriptor
Warning:org.hamcrest.beans.HasPropertyWithValue$2: can't find referenced class java.beans.PropertyDescriptor
Warning:org.hamcrest.beans.PropertyUtil: can't find referenced class java.beans.PropertyDescriptor
Warning:org.hamcrest.beans.PropertyUtil: can't find referenced class java.beans.Introspector
Warning:org.hamcrest.beans.PropertyUtil: can't find referenced class java.beans.BeanInfo
Warning:org.hamcrest.beans.PropertyUtil: can't find referenced class java.beans.IntrospectionException
Warning:org.hamcrest.beans.PropertyUtil: can't find referenced class java.beans.PropertyDescriptor
Warning:org.hamcrest.beans.PropertyUtil: can't find referenced class java.beans.Introspector
Warning:org.hamcrest.beans.PropertyUtil: can't find referenced class java.beans.BeanInfo
Warning:org.hamcrest.beans.PropertyUtil: can't find referenced class java.beans.PropertyDescriptor
Warning:org.hamcrest.beans.PropertyUtil: can't find referenced class java.beans.IntrospectionException
Warning:org.hamcrest.beans.PropertyUtil: can't find referenced class java.beans.PropertyDescriptor
Warning:org.hamcrest.beans.SamePropertyValuesAs: can't find referenced class java.beans.PropertyDescriptor
Warning:org.hamcrest.beans.SamePropertyValuesAs$PropertyMatcher: can't find referenced class java.beans.PropertyDescriptor
Warning:org.hamcrest.integration.EasyMock2Adapter: can't find referenced class org.easymock.EasyMock
Warning:org.hamcrest.integration.EasyMock2Adapter: can't find referenced class org.easymock.IArgumentMatcher
Warning:org.hamcrest.integration.EasyMock2Adapter: can't find referenced class org.easymock.EasyMock
Warning:org.hamcrest.integration.EasyMock2Adapter: can't find referenced class org.easymock.IArgumentMatcher
Warning:org.hamcrest.integration.JMock1Adapter: can't find referenced class org.jmock.core.Constraint
Warning:org.junit.internal.runners.statements.FailOnTimeout: can't find referenced class java.lang.management.ManagementFactory
Warning:org.junit.internal.runners.statements.FailOnTimeout: can't find referenced class java.lang.management.ThreadMXBean
Warning:org.junit.internal.runners.statements.FailOnTimeout: can't find referenced class java.lang.management.ManagementFactory
Warning:org.junit.internal.runners.statements.FailOnTimeout: can't find referenced class java.lang.management.ThreadMXBean
Warning:org.junit.rules.DisableOnDebug: can't find referenced class java.lang.management.ManagementFactory
Warning:org.junit.rules.DisableOnDebug: can't find referenced class java.lang.management.RuntimeMXBean
Warning:org.junit.rules.DisableOnDebug: can't find referenced class java.lang.management.ManagementFactory
Warning:org.junit.rules.DisableOnDebug: can't find referenced class java.lang.management.RuntimeMXBean
Warning:there were 118 unresolved references to classes or interfaces.
Warning:there were 5 instances of library classes depending on program classes.
Warning:there were 3 unresolved references to program class members.
Warning:Exception while processing task java.io.IOException: Please correct the above warnings first.
Error:Execution failed for task ':app:transformClassesAndResourcesWithProguardForDebugAndroidTest'.
> Job failed, see logs for details
Information:BUILD FAILED
Information:Total time: 8.388 secs
Information:1 error
Information:48 warnings
Information:See complete output in console
I think I need to add some procured rules for this android.arch.persistence.room:testing:1.0.0-alpha9 but I don't know what.
thank you for your help.

Proguard causes 100 "can't find referenced class" warnings, ignores keep rules for springframework and jackson

My code compiles and runs fine in debug mode, but once I use a build configuration with minifyEnabled true I get these warnings which prevent compilation:
Warning:there were 100 unresolved references to classes or interfaces.
Warning:there were 2 unresolved references to program class members.
For readabilities sake I'll include the full output at the bottom.
There are two libraries that are causing these warnings, springframework and jackson. Those libraries are included in my project via gradle like so:
compile 'com.fasterxml.jackson.core:jackson-annotations:2.8.5'
compile 'com.fasterxml.jackson.core:jackson-core:2.8.5'
compile 'com.fasterxml.jackson.core:jackson-databind:2.8.5'
apt "org.androidannotations:rest-spring:$AAVersion"
compile "org.androidannotations:rest-spring-api:$AAVersion"
compile 'org.springframework.android:spring-android-rest-template:2.0.0.M3'
If I use -dontwarn for both of these libraries, like many people suggest for these types of issues, the app compiles but crashes with an obfuscated crashlog during startup - I tried retracing it with the mapping file, but that's not working either - I'm reasonably certain that the app crashes due to the autogenerated (through android annotations) class RestClient_ when initializing a jackson mapping class, the exception is the following:
java.lang.NoSuchFieldError: No static field PUBLIC_ONLY of type
Lcom/myapp/app/mv$a; in class Lcom/myapp/app/mv$a; or its superclasses
(declaration of 'com.myapp.app.mv$a' appears in
/data/app/com.myapp.app-1/base.apk)
Although on a different phone, the exception has no message. It's pretty obvious that this is a result of proguard.
My full proguard file can be found here https://gist.github.com/Syzygy2048/02a44032611d40720bad36b5e3b37db6
Here are a couple of things I already tried (I tried more, but I only started writing things down after a while). The attempts focus on fixing springframework first. (Had to put this in a gist because stackoverflow wouldn't let me post otherwise)
https://gist.github.com/Syzygy2048/f1bdabc9f2ea091aa8faec67c62dd8bb
full error log:
Information:Gradle tasks [:myappApp:assembleMyappPublicRelease]
Warning:org.springframework.core.convert.support.ConvertingPropertyEditorAdapter: can't find superclass or interface java.beans.PropertyEditorSupport
Warning:com.fasterxml.jackson.databind.ext.DOMSerializer: can't find referenced class org.w3c.dom.bootstrap.DOMImplementationRegistry
Warning:com.fasterxml.jackson.databind.ext.Java7SupportImpl: can't find referenced class java.beans.Transient
Warning:com.fasterxml.jackson.databind.ext.Java7SupportImpl: can't find referenced class java.beans.ConstructorProperties
Warning:com.fasterxml.jackson.databind.ext.Java7SupportImpl: can't find referenced class java.nio.file.Path
Warning:com.fasterxml.jackson.databind.ext.Java7SupportImpl: can't find referenced class java.beans.Transient
Warning:com.fasterxml.jackson.databind.ext.Java7SupportImpl: can't find referenced class java.beans.ConstructorProperties
Warning:com.fasterxml.jackson.databind.ext.Java7SupportImpl: can't find referenced class java.beans.Transient
Warning:com.fasterxml.jackson.databind.ext.Java7SupportImpl: can't find referenced class java.beans.ConstructorProperties
Warning:com.fasterxml.jackson.databind.ext.Java7SupportImpl: can't find referenced class java.beans.Transient
Warning:com.fasterxml.jackson.databind.ext.Java7SupportImpl: can't find referenced class java.beans.ConstructorProperties
Warning:com.fasterxml.jackson.databind.ext.NioPathDeserializer: can't find referenced class java.nio.file.Path
Warning:com.fasterxml.jackson.databind.ext.NioPathDeserializer: can't find referenced class java.nio.file.Paths
Warning:com.fasterxml.jackson.databind.ext.NioPathDeserializer: can't find referenced class java.nio.file.Path
Warning:com.fasterxml.jackson.databind.ext.NioPathSerializer: can't find referenced class java.nio.file.Path
Warning:org.springframework.core.convert.support.ConvertingPropertyEditorAdapter: can't find referenced class java.beans.PropertyEditorSupport
Warning:org.springframework.core.convert.support.ConvertingPropertyEditorAdapter: can't find referenced method 'void setValue(java.lang.Object)' in program class org.springframework.core.convert.support.ConvertingPropertyEditorAdapter
Warning:org.springframework.core.convert.support.ConvertingPropertyEditorAdapter: can't find referenced method 'java.lang.Object getValue()' in program class org.springframework.core.convert.support.ConvertingPropertyEditorAdapter
Warning:org.springframework.core.convert.support.ConvertingPropertyEditorAdapter: can't find referenced class java.beans.PropertyEditorSupport
Warning:org.springframework.http.client.HttpComponentsClientHttpRequest: can't find referenced class org.apache.http.entity.ByteArrayEntityHC4
Warning:org.springframework.http.client.HttpComponentsClientHttpRequest: can't find referenced class org.apache.http.impl.client.CloseableHttpClient
Warning:org.springframework.http.client.HttpComponentsClientHttpRequest: can't find referenced class org.apache.http.client.methods.CloseableHttpResponse
Warning:org.springframework.http.client.HttpComponentsClientHttpRequestFactory: can't find referenced class org.apache.http.impl.client.HttpClients
Warning:org.springframework.http.client.HttpComponentsClientHttpRequestFactory: can't find referenced class org.apache.http.impl.client.CloseableHttpClient
Warning:org.springframework.http.client.HttpComponentsClientHttpRequestFactory: can't find referenced class org.apache.http.client.protocol.HttpClientContext
Warning:org.springframework.http.client.HttpComponentsClientHttpRequestFactory: can't find referenced class org.apache.http.client.methods.Configurable
Warning:org.springframework.http.client.HttpComponentsClientHttpRequestFactory: can't find referenced class org.apache.http.client.config.RequestConfig
Warning:org.springframework.http.client.HttpComponentsClientHttpRequestFactory: can't find referenced class org.apache.http.client.config.RequestConfig$Builder
Warning:org.springframework.http.client.HttpComponentsClientHttpRequestFactory: can't find referenced class org.apache.http.client.config.RequestConfig
Warning:org.springframework.http.client.HttpComponentsClientHttpRequestFactory: can't find referenced class org.apache.http.client.methods.HttpGetHC4
Warning:org.springframework.http.client.HttpComponentsClientHttpRequestFactory: can't find referenced class org.apache.http.client.methods.HttpDeleteHC4
Warning:org.springframework.http.client.HttpComponentsClientHttpRequestFactory: can't find referenced class org.apache.http.client.methods.HttpHeadHC4
Warning:org.springframework.http.client.HttpComponentsClientHttpRequestFactory: can't find referenced class org.apache.http.client.methods.HttpOptionsHC4
Warning:org.springframework.http.client.HttpComponentsClientHttpRequestFactory: can't find referenced class org.apache.http.client.methods.HttpPostHC4
Warning:org.springframework.http.client.HttpComponentsClientHttpRequestFactory: can't find referenced class org.apache.http.client.methods.HttpPutHC4
Warning:org.springframework.http.client.HttpComponentsClientHttpRequestFactory: can't find referenced class org.apache.http.client.methods.HttpTraceHC4
Warning:org.springframework.http.client.HttpComponentsClientHttpRequestFactory: can't find referenced class org.apache.http.client.methods.HttpPatch
Warning:org.springframework.http.client.HttpComponentsClientHttpRequestFactory: can't find referenced class org.apache.http.impl.client.CloseableHttpClient
Warning:org.springframework.http.client.HttpComponentsClientHttpRequestFactory: can't find referenced class org.apache.http.client.config.RequestConfig
Warning:org.springframework.http.client.HttpComponentsClientHttpRequestFactory: can't find referenced class org.apache.http.impl.client.HttpClients
Warning:org.springframework.http.client.HttpComponentsClientHttpRequestFactory: can't find referenced class org.apache.http.client.protocol.HttpClientContext
Warning:org.springframework.http.client.HttpComponentsClientHttpRequestFactory: can't find referenced class org.apache.http.client.config.RequestConfig
Warning:org.springframework.http.client.HttpComponentsClientHttpRequestFactory: can't find referenced class org.apache.http.client.config.RequestConfig$Builder
Warning:org.springframework.http.client.HttpComponentsClientHttpRequestFactory: can't find referenced class org.apache.http.impl.client.CloseableHttpClient
Warning:org.springframework.http.client.HttpComponentsClientHttpRequestFactory: can't find referenced class org.apache.http.client.config.RequestConfig
Warning:org.springframework.http.client.HttpComponentsClientHttpRequestFactory: can't find referenced class org.apache.http.impl.client.CloseableHttpClient
Warning:org.springframework.http.client.HttpComponentsClientHttpResponse: can't find referenced class org.apache.http.client.methods.CloseableHttpResponse
Warning:org.springframework.http.client.HttpComponentsClientHttpResponse: can't find referenced class org.apache.http.util.EntityUtilsHC4
Warning:org.springframework.http.client.HttpComponentsClientHttpResponse: can't find referenced class org.apache.http.client.methods.CloseableHttpResponse
Warning:org.springframework.http.client.HttpComponentsClientHttpResponse: can't find referenced class org.apache.http.util.EntityUtilsHC4
Warning:org.springframework.http.client.HttpComponentsClientHttpResponse: can't find referenced class org.apache.http.client.methods.CloseableHttpResponse
Warning:org.springframework.http.client.HttpComponentsStreamingClientHttpRequest: can't find referenced class org.apache.http.impl.client.CloseableHttpClient
Warning:org.springframework.http.client.HttpComponentsStreamingClientHttpRequest: can't find referenced class org.apache.http.client.methods.CloseableHttpResponse
Warning:org.springframework.http.converter.xml.SimpleXmlHttpMessageConverter: can't find referenced class org.simpleframework.xml.core.Persister
Warning:org.springframework.http.converter.xml.SimpleXmlHttpMessageConverter: can't find referenced class org.simpleframework.xml.Root
Warning:org.springframework.http.converter.xml.SimpleXmlHttpMessageConverter: can't find referenced class org.simpleframework.xml.Serializer
Warning:there were 100 unresolved references to classes or interfaces.
Warning:there were 2 unresolved references to program class members.
Warning:Exception while processing task java.io.IOException: Please correct the above warnings first.
Error:Execution failed for task ':myappApp:transformClassesAndResourcesWithProguardForMyappPublicRelease'.
Job failed, see logs for details
Information:BUILD FAILED
Information:Total time: 23.68 secs
Information:1 error
Information:59 warnings
Information:See complete output in console

It turns out that adding this to my proguard file fixed my issues.
-keepclassmembers class com.myapp.models.** {
*; }
-keep class com.fasterxml.jackson.annotation.** { *; }
-dontwarn com.fasterxml.jackson.databind.**
-dontwarn org.springframework.**
So in the end I could ignore most of those warnings after all. As I said simply ignoring them lead to crashes, which are fixed by not obfuscating jackson annotations and by not obfuscating my model classes which seem to be needed so that the json <--> pojo conversion can happen.

Android proguard crashed when Azure mobile app is used

I use Azure mobile app in my new Android project.
When I run the app on debug mode, the Mobile app works successfully and I can see my new records in my table.
My problem is starting when I creates an apk file with proguard.
I am sorry to say that I am newbie on Proguard then I can not solve my Proguard problems even I read the documentation at offical Proguard page.
So, I get these errors when I try to create apk file with Proguard without any Proguard code.
Warning: com.google.common.base.Absent: can't find referenced class javax.annotation.Nullable
Warning: com.google.common.base.Absent: can't find referenced class javax.annotation.Nullable
Warning: com.google.common.base.Ascii: can't find referenced class javax.annotation.CheckReturnValue
Warning: com.google.common.base.CaseFormat$StringConverter: can't find referenced class javax.annotation.Nullable
Warning: com.google.common.base.CharMatcher: can't find referenced class javax.annotation.CheckReturnValue
Warning: com.google.common.base.CharMatcher: can't find referenced class javax.annotation.CheckReturnValue
Warning: com.google.common.base.CharMatcher: can't find referenced class javax.annotation.CheckReturnValue
and more hundreads line...
Warning: com.google.common.cache.Striped64: can't find referenced class sun.misc.Unsafe
Warning: com.google.common.cache.Striped64: can't find referenced class sun.misc.Unsafe
Warning: com.google.common.cache.Striped64: can't find referenced class sun.misc.Unsafe
Warning: com.google.common.cache.Striped64: can't find referenced class sun.misc.Unsafe
Warning: com.google.common.cache.Striped64$1: can't find referenced class sun.misc.Unsafe
Warning: com.google.common.cache.Striped64$1: can't find referenced class sun.misc.Unsafe
Warning: com.google.common.cache.Striped64$1: can't find referenced class sun.misc.Unsafe
Warning: com.google.common.cache.Striped64$1: can't find referenced class sun.misc.Unsafe
and more hundreads line....
Warning: okio.Okio: can't find referenced class java.nio.file.Files
Warning: okio.Okio: can't find referenced class java.nio.file.Files
Warning: okio.Okio: can't find referenced class java.nio.file.Files
Warning: okio.Okio: can't find referenced class java.nio.file.Path
Warning: okio.Okio: can't find referenced class java.nio.file.OpenOption
Warning: okio.Okio: can't find referenced class java.nio.file.Path
Warning: okio.Okio: can't find referenced class java.nio.file.OpenOption
Warning: okio.Okio: can't find referenced class org.codehaus.mojo.animal_sniffer.IgnoreJRERequirement
Warning: okio.Okio: can't find referenced class java.nio.file.Path
Warning: okio.Okio: can't find referenced class java.nio.file.OpenOption
Warning: okio.Okio: can't find referenced class java.nio.file.Path
Warning: okio.Okio: can't find referenced class java.nio.file.OpenOption
Warning: okio.Okio: can't find referenced class org.codehaus.mojo.animal_sniffer.IgnoreJRERequirement
Then I added these line in my proguard.
-keep class okio.** { *; }
-dontwarn okio.**
-keep class com.fasterxml.** { *; }
-dontwarn com.fasterxml.**
-dontwarn javax.annotation.**
-dontwarn javax.inject.**
-dontwarn sun.misc.Unsafe
-keep class com.microsoft.windowsazure.mobileservices.** { *; }
-dontwarn android.os.**
-dontwarn com.microsoft.windowsazure.mobileservices.RequestAsyncTask
After that, Android studio created the apk however The app crahsed as soon as It started. Then I investigate the logs, I saw new warnings that color are white.
Note: duplicate definition of library class [org.apache.http.conn.scheme.LayeredSocketFactory]
Note: duplicate definition of library class [org.apache.http.conn.scheme.SocketFactory]
Note: duplicate definition of library class [org.apache.http.conn.scheme.HostNameResolver]
Note: duplicate definition of library class [org.apache.http.conn.ConnectTimeoutException]
Note: duplicate definition of library class [org.apache.http.params.CoreConnectionPNames]
Note: duplicate definition of library class [org.apache.http.params.HttpParams]
Note: duplicate definition of library class [org.apache.http.params.HttpConnectionParams]
Note: duplicate definition of library class [android.net.http.SslError]
Note: duplicate definition of library class [android.net.http.HttpResponseCache]
Note: duplicate definition of library class [android.net.http.SslCertificate$DName]
Note: duplicate definition of library class [android.net.http.SslCertificate]
Note: there were 11 duplicate class definitions.
(http://proguard.sourceforge.net/manual/troubleshooting.html#duplicateclass)
Thanks for help.

#MustafaOlkun, It seems that the solutions for your issues can be found at the troubleshooting page of ProGuard.
For the issue Warning: can't find referenced class, please see http://proguard.sourceforge.net/manual/troubleshooting.html#unresolvedclass.
For the issue Note: duplicate definition of library class, please see http://proguard.sourceforge.net/manual/troubleshooting.html#duplicateclass.
Hope it helps.

Is there an valid proguard rule for RxJava and FasterXML?

Now the only problem stopping me from using kotlin in production is that I can't find a correct proguard file for it.
What I used:
1.Kotlin
2.Anko
3.Jackson-Kotlin-module
Here's the warning message:
:app:proguardRelease
Warning: com.fasterxml.jackson.databind.ext.DOMSerializer: can't find referenced class org.w3c.dom.bootstrap.DOMImplementationRegistry
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.UnsafeAccess: can't find referenced class sun.misc.Unsafe
Warning: there were 41 unresolved references to classes or interfaces.

It has nothing to do with Kotlin. Ignore the warnings in your proguard file:
-dontwarn sun.misc.Unsafe
-dontwarn org.w3c.dom.bootstrap.DOMImplementationRegistry

a better is just to have this aar as a dependency:
https://github.com/artem-zinnatullin/RxJavaProGuardRules

Android Proguard errors on compile

I'm using proguard for the first time, and when I compiled the app I received the following error stack:
Note: there were 1 duplicate class definitions.
(http://proguard.sourceforge.net/manual/troubleshooting.html#duplicateclass)
Warning:org.codehaus.jackson.map.ext.DOMSerializer: can't find referenced class org.w3c.dom.bootstrap.DOMImplementationRegistry
Warning:org.codehaus.jackson.map.ext.JodaDeserializers: can't find referenced class org.joda.time.DateTime
Warning:org.codehaus.jackson.map.ext.JodaDeserializers: can't find referenced class org.joda.time.ReadableDateTime
Warning:org.codehaus.jackson.map.ext.JodaDeserializers: can't find referenced class org.joda.time.ReadableInstant
Warning:org.codehaus.jackson.map.ext.JodaDeserializers$DateMidnightDeserializer: can't find referenced class org.joda.time.DateMidnight
Warning:org.codehaus.jackson.map.ext.JodaDeserializers$DateMidnightDeserializer: can't find referenced class org.joda.time.DateTime
Warning:org.codehaus.jackson.map.ext.JodaDeserializers$DateMidnightDeserializer: can't find referenced class org.joda.time.DateMidnight
Warning:org.codehaus.jackson.map.ext.JodaDeserializers$DateMidnightDeserializer: can't find referenced class org.joda.time.DateTime
Warning:org.codehaus.jackson.map.ext.JodaDeserializers$DateMidnightDeserializer: can't find referenced class org.joda.time.DateMidnight
Warning:org.codehaus.jackson.map.ext.JodaDeserializers$DateTimeDeserializer: can't find referenced class org.joda.time.DateTime
Warning:org.codehaus.jackson.map.ext.JodaDeserializers$DateTimeDeserializer: can't find referenced class org.joda.time.DateTimeZone
Warning:org.codehaus.jackson.map.ext.JodaDeserializers$DateTimeDeserializer: can't find referenced class org.joda.time.DateTime
Warning:org.codehaus.jackson.map.ext.JodaDeserializers$DateTimeDeserializer: can't find referenced class org.joda.time.ReadableInstant
Warning:org.codehaus.jackson.map.ext.JodaDeserializers$JodaDeserializer: can't find referenced class org.joda.time.format.DateTimeFormatter
Warning:org.codehaus.jackson.map.ext.JodaDeserializers$JodaDeserializer: can't find referenced class org.joda.time.format.ISODateTimeFormat
Warning:org.codehaus.jackson.map.ext.JodaDeserializers$JodaDeserializer: can't find referenced class org.joda.time.format.DateTimeFormatter
Warning:org.codehaus.jackson.map.ext.JodaDeserializers$JodaDeserializer: can't find referenced class org.joda.time.DateTime
Warning:org.codehaus.jackson.map.ext.JodaDeserializers$LocalDateDeserializer: can't find referenced class org.joda.time.LocalDate
Warning:org.codehaus.jackson.map.ext.JodaDeserializers$LocalDateDeserializer: can't find referenced class org.joda.time.DateTime
Warning:org.codehaus.jackson.map.ext.JodaDeserializers$LocalDateDeserializer: can't find referenced class org.joda.time.LocalDate
Warning:org.codehaus.jackson.map.ext.JodaDeserializers$LocalDateDeserializer: can't find referenced class org.joda.time.DateTime
Warning:org.codehaus.jackson.map.ext.JodaDeserializers$LocalDateDeserializer: can't find referenced class org.joda.time.LocalDate
Warning:org.codehaus.jackson.map.ext.JodaDeserializers$LocalDateTimeDeserializer: can't find referenced class org.joda.time.LocalDateTime
Warning:org.codehaus.jackson.map.ext.JodaDeserializers$LocalDateTimeDeserializer: can't find referenced class org.joda.time.DateTime
Warning:org.codehaus.jackson.map.ext.JodaDeserializers$LocalDateTimeDeserializer: can't find referenced class org.joda.time.LocalDateTime
Warning:org.codehaus.jackson.map.ext.JodaDeserializers$LocalDateTimeDeserializer: can't find referenced class org.joda.time.DateTime
Warning:org.codehaus.jackson.map.ext.JodaDeserializers$LocalDateTimeDeserializer: can't find referenced class org.joda.time.LocalDateTime
Warning:org.codehaus.jackson.map.ext.JodaSerializers: can't find referenced class org.joda.time.DateTime
Warning:org.codehaus.jackson.map.ext.JodaSerializers: can't find referenced class org.joda.time.LocalDateTime
Warning:org.codehaus.jackson.map.ext.JodaSerializers: can't find referenced class org.joda.time.LocalDate
Warning:org.codehaus.jackson.map.ext.JodaSerializers: can't find referenced class org.joda.time.DateMidnight
Warning:org.codehaus.jackson.map.ext.JodaSerializers$DateMidnightSerializer: can't find referenced class org.joda.time.DateMidnight$Property
Warning:org.codehaus.jackson.map.ext.JodaSerializers$DateMidnightSerializer: can't find referenced class org.joda.time.DateMidnight
Warning:org.codehaus.jackson.map.ext.JodaSerializers$DateMidnightSerializer: can't find referenced class org.joda.time.DateMidnight$Property
Warning:org.codehaus.jackson.map.ext.JodaSerializers$DateMidnightSerializer: can't find referenced class org.joda.time.DateMidnight
Warning:org.codehaus.jackson.map.ext.JodaSerializers$DateTimeSerializer: can't find referenced class org.joda.time.DateTime
Warning:org.codehaus.jackson.map.ext.JodaSerializers$JodaSerializer: can't find referenced class org.joda.time.format.DateTimeFormatter
Warning:org.codehaus.jackson.map.ext.JodaSerializers$JodaSerializer: can't find referenced class org.joda.time.format.ISODateTimeFormat
Warning:org.codehaus.jackson.map.ext.JodaSerializers$JodaSerializer: can't find referenced class org.joda.time.format.DateTimeFormatter
Warning:org.codehaus.jackson.map.ext.JodaSerializers$JodaSerializer: can't find referenced class org.joda.time.ReadablePartial
Warning:org.codehaus.jackson.map.ext.JodaSerializers$JodaSerializer: can't find referenced class org.joda.time.ReadableInstant
Warning:org.codehaus.jackson.map.ext.JodaSerializers$LocalDateSerializer: can't find referenced class org.joda.time.LocalDate$Property
Warning:org.codehaus.jackson.map.ext.JodaSerializers$LocalDateSerializer: can't find referenced class org.joda.time.LocalDate
Warning:org.codehaus.jackson.map.ext.JodaSerializers$LocalDateSerializer: can't find referenced class org.joda.time.LocalDate$Property
Warning:org.codehaus.jackson.map.ext.JodaSerializers$LocalDateSerializer: can't find referenced class org.joda.time.LocalDate
Warning:org.codehaus.jackson.map.ext.JodaSerializers$LocalDateTimeSerializer: can't find referenced class org.joda.time.LocalDateTime$Property
Warning:org.codehaus.jackson.map.ext.JodaSerializers$LocalDateTimeSerializer: can't find referenced class org.joda.time.LocalDateTime
Warning:org.codehaus.jackson.map.ext.JodaSerializers$LocalDateTimeSerializer: can't find referenced class org.joda.time.LocalDateTime$Property
Warning:org.codehaus.jackson.map.ext.JodaSerializers$LocalDateTimeSerializer: can't find referenced class org.joda.time.LocalDateTime
Warning:there were 99 unresolved references to classes or interfaces.
You may need to add missing library jars or update their versions.
If your code works fine without the missing classes, you can suppress
the warnings with '-dontwarn' options.
(http://proguard.sourceforge.net/manual/troubleshooting.html#unresolvedclass)
:app:proguardDebug FAILED
I tried with both the basic changes to proguard-rules.txt and with everything in that file commented out and get the same result, so the contents of that (or lack thereof) don't seem to have any bearing on this error being thrown.
As you can see, there isn't anything pointing to what exactly is duplicate. Also, the warning lines below the message about duplication reference a package I don't use anywhere in my app.
I've tried searching for this problem and attempted to add some lines such as
-keep class android.support.v4.** { *; }
which someone suggested but that didn't do the trick.
Here is something in the build.gradle file for my app which is raising a flag:
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.txt'
I have a file proguard-rules.txt in the root folder of my app (the same directory as my build.gradle file), but I don't have a proguard-android.txt file there, or anywhere else I could find for that matter. Could that be a cause?
Any ideas? Thanks!

You actually don't have any errors, these are warnings which, according to what the log says,
If your code works fine without the missing classes, you can suppress
the warnings with '-dontwarn' options.
can be suppressed with the following line in the ProGuard config:
-dontwarn org.codehaus.jackson.map.ext.**

Add on your PROGuard file:
-dontwarn org.joda.convert.**
-dontwarn org.codehaus.jackson.map.ext.**
-keep class org.w3c.dom.bootstrap.** { *; }
-keep class org.joda.time.** { *; }

Try adding the following to your proguard config:
-keep class org.w3c.dom.bootstrap.** { *; }
-keep class org.joda.time.** { *; }