convert top level classes to kotlin (#6368)

* Converted welcome activity / pager to kotlin

* Removed unused interface

* Convert ViewPagerAdapter to kotlin and enforce that all tabs must have a title that comes from strings.xml

* Convert OkHttpConnectionFactory and remove an exception class nobody was using

* Convert MapController to kotlin along with fixing nullability in a few places

app/src/test/kotlin/fr/free/nrw/commons/MockWebServerTest.java

@@ -1,110 +0,0 @@
-package fr.free.nrw.commons;
-
-import static fr.free.nrw.commons.TestConnectionFactoryKt.createTestClient;
-
-import androidx.annotation.NonNull;
-import java.util.List;
-import java.util.concurrent.AbstractExecutorService;
-import java.util.concurrent.Executor;
-import java.util.concurrent.TimeUnit;
-import okhttp3.Dispatcher;
-import okhttp3.OkHttpClient;
-import okhttp3.mockwebserver.MockResponse;
-import org.junit.After;
-import org.junit.Before;
-import org.junit.runner.RunWith;
-import org.robolectric.RobolectricTestRunner;
-import fr.free.nrw.commons.wikidata.GsonUtil;
-import retrofit2.Retrofit;
-import retrofit2.converter.gson.GsonConverterFactory;
-
-@RunWith(RobolectricTestRunner.class)
-public abstract class MockWebServerTest {
-    private OkHttpClient okHttpClient;
-    private final TestWebServer server = new TestWebServer();
-
-    @Before public void setUp() throws Throwable {
-        OkHttpConnectionFactory.CLIENT = createTestClient();
-        okHttpClient = OkHttpConnectionFactory.CLIENT.newBuilder()
-            .dispatcher(new Dispatcher(new ImmediateExecutorService())).build();
-        server.setUp();
-    }
-
-    @After public void tearDown() throws Throwable {
-        server.tearDown();
-    }
-
-    @NonNull protected TestWebServer server() {
-        return server;
-    }
-
-    protected void enqueueFromFile(@NonNull String filename) throws Throwable {
-        String json = TestFileUtil.readRawFile(filename);
-        server.enqueue(json);
-    }
-
-    protected void enqueue404() {
-        final int code = 404;
-        server.enqueue(new MockResponse().setResponseCode(code).setBody("Not Found"));
-    }
-
-    protected void enqueueMalformed() {
-        server.enqueue("(╯°□°）╯︵ ┻━┻");
-    }
-
-    protected void enqueueEmptyJson() {
-        server.enqueue(new MockResponse().setBody("{}"));
-    }
-
-    @NonNull protected OkHttpClient okHttpClient() {
-        return okHttpClient;
-    }
-
-    @NonNull protected <T> T service(Class<T> clazz) {
-        return service(clazz, server().getUrl());
-    }
-
-    @NonNull protected <T> T service(Class<T> clazz, @NonNull String url) {
-        return new Retrofit.Builder()
-                .baseUrl(url)
-                .callbackExecutor(new ImmediateExecutor())
-                .client(okHttpClient)
-                .addConverterFactory(GsonConverterFactory.create(GsonUtil.INSTANCE.getDefaultGson()))
-                .build()
-                .create(clazz);
-    }
-
-    public final class ImmediateExecutorService extends AbstractExecutorService {
-        @Override public void shutdown() {
-            throw new UnsupportedOperationException();
-        }
-
-        @NonNull @Override public List<Runnable> shutdownNow() {
-            throw new UnsupportedOperationException();
-        }
-
-        @Override public boolean isShutdown() {
-            throw new UnsupportedOperationException();
-        }
-
-        @Override public boolean isTerminated() {
-            throw new UnsupportedOperationException();
-        }
-
-        @Override public boolean awaitTermination(long l, @NonNull TimeUnit timeUnit)
-            throws InterruptedException {
-            throw new UnsupportedOperationException();
-        }
-
-        @Override public void execute(@NonNull Runnable runnable) {
-            runnable.run();
-        }
-    }
-
-    public class ImmediateExecutor implements Executor {
-        @Override
-        public void execute(@NonNull Runnable runnable) {
-            runnable.run();
-        }
-    }
-}

app/src/test/kotlin/fr/free/nrw/commons/MockWebServerTest.kt

@@ -0,0 +1,110 @@
+package fr.free.nrw.commons
+
+import fr.free.nrw.commons.wikidata.GsonUtil.defaultGson
+import okhttp3.Dispatcher
+import okhttp3.OkHttpClient
+import okhttp3.mockwebserver.MockResponse
+import org.junit.After
+import org.junit.Before
+import org.junit.runner.RunWith
+import org.robolectric.RobolectricTestRunner
+import retrofit2.Retrofit
+import retrofit2.converter.gson.GsonConverterFactory
+import java.util.concurrent.AbstractExecutorService
+import java.util.concurrent.Executor
+import java.util.concurrent.TimeUnit
+
+@RunWith(RobolectricTestRunner::class)
+abstract class MockWebServerTest {
+    private var okHttpClient: OkHttpClient? = null
+    private val server = TestWebServer()
+
+    @Before
+    @Throws(Throwable::class)
+    open fun setUp() {
+        OkHttpConnectionFactory.CLIENT = createTestClient()
+        okHttpClient = OkHttpConnectionFactory.CLIENT!!.newBuilder()
+            .dispatcher(Dispatcher(ImmediateExecutorService())).build()
+        server.setUp()
+    }
+
+    @After
+    @Throws(Throwable::class)
+    fun tearDown() {
+        server.tearDown()
+    }
+
+    protected fun server(): TestWebServer {
+        return server
+    }
+
+    @Throws(Throwable::class)
+    protected fun enqueueFromFile(filename: String) {
+        val json = TestFileUtil.readRawFile(filename)
+        server.enqueue(json)
+    }
+
+    protected fun enqueue404() {
+        val code = 404
+        server.enqueue(MockResponse().setResponseCode(code).setBody("Not Found"))
+    }
+
+    protected fun enqueueMalformed() {
+        server.enqueue("(╯°□°）╯︵ ┻━┻")
+    }
+
+    protected fun enqueueEmptyJson() {
+        server.enqueue(MockResponse().setBody("{}"))
+    }
+
+    protected fun okHttpClient(): OkHttpClient {
+        return okHttpClient!!
+    }
+
+    protected fun <T> service(clazz: Class<T>): T {
+        return service(clazz, server().url)
+    }
+
+    protected fun <T> service(clazz: Class<T>, url: String): T {
+        return Retrofit.Builder()
+            .baseUrl(url)
+            .callbackExecutor(ImmediateExecutor())
+            .client(okHttpClient)
+            .addConverterFactory(GsonConverterFactory.create(defaultGson))
+            .build()
+            .create(clazz)
+    }
+
+    inner class ImmediateExecutorService : AbstractExecutorService() {
+        override fun shutdown() {
+            throw UnsupportedOperationException()
+        }
+
+        override fun shutdownNow(): List<Runnable> {
+            throw UnsupportedOperationException()
+        }
+
+        override fun isShutdown(): Boolean {
+            throw UnsupportedOperationException()
+        }
+
+        override fun isTerminated(): Boolean {
+            throw UnsupportedOperationException()
+        }
+
+        @Throws(InterruptedException::class)
+        override fun awaitTermination(l: Long, timeUnit: TimeUnit): Boolean {
+            throw UnsupportedOperationException()
+        }
+
+        override fun execute(runnable: Runnable) {
+            runnable.run()
+        }
+    }
+
+    inner class ImmediateExecutor : Executor {
+        override fun execute(runnable: Runnable) {
+            runnable.run()
+        }
+    }
+}

app/src/test/kotlin/fr/free/nrw/commons/TestConnectionFactory.kt

@@ -1,6 +1,5 @@
 package fr.free.nrw.commons
 
-import fr.free.nrw.commons.OkHttpConnectionFactory.HttpStatusException
 import okhttp3.Interceptor
 import okhttp3.OkHttpClient
 import okhttp3.Response
@@ -39,6 +38,6 @@ private class UnsuccessfulResponseInterceptor : Interceptor {
         if (rsp.isSuccessful) {
             return rsp
         }
-        throw HttpStatusException(rsp)
+        throw IOException("Unsuccessful response")
     }
 }

app/src/test/kotlin/fr/free/nrw/commons/auth/csrf/CsrfTokenClientTest.kt

@@ -2,7 +2,6 @@ package fr.free.nrw.commons.auth.csrf
 
 import com.google.gson.stream.MalformedJsonException
 import fr.free.nrw.commons.MockWebServerTest
-import fr.free.nrw.commons.OkHttpConnectionFactory.HttpStatusException
 import fr.free.nrw.commons.auth.SessionManager
 import fr.free.nrw.commons.auth.login.LoginClient
 import fr.free.nrw.commons.wikidata.mwapi.MwException
@@ -13,6 +12,7 @@ import org.mockito.ArgumentMatchers.isA
 import org.mockito.Mockito.mock
 import org.mockito.Mockito.never
 import org.mockito.Mockito.verify
+import java.io.IOException
 
 class CsrfTokenClientTest : MockWebServerTest() {
     private val cb = mock(CsrfTokenClient.Callback::class.java)
@@ -53,7 +53,7 @@ class CsrfTokenClientTest : MockWebServerTest() {
         performRequest()
 
         verify(cb, never()).success(any(String::class.java))
-        verify(cb).failure(isA(HttpStatusException::class.java))
+        verify(cb).failure(isA(IOException::class.java))
     }
 
     @Test