diff --git a/examples/android/clientcache/app/build.gradle b/examples/android/clientcache/app/build.gradle
new file mode 100644
index 0000000000..5c0c647dcd
--- /dev/null
+++ b/examples/android/clientcache/app/build.gradle
@@ -0,0 +1,67 @@
+apply plugin: 'com.android.application'
+apply plugin: 'com.google.protobuf'
+
+android {
+ compileSdkVersion 25
+ buildToolsVersion "25.0.2"
+
+ defaultConfig {
+ applicationId "io.grpc.android.clientcacheexample"
+ minSdkVersion 19
+ targetSdkVersion 25
+ multiDexEnabled true
+ versionCode 1
+ versionName "1.0"
+ testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
+ }
+ buildTypes {
+ release {
+ minifyEnabled true
+ proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
+ }
+ }
+ lintOptions {
+ disable 'InvalidPackage', 'HardcodedText'
+ textReport true
+ textOutput "stdout"
+ }
+}
+
+protobuf {
+ protoc {
+ artifact = 'com.google.protobuf:protoc:3.4.0'
+ }
+ plugins {
+ javalite {
+ artifact = "com.google.protobuf:protoc-gen-javalite:3.0.0"
+ }
+ grpc {
+ artifact = 'io.grpc:protoc-gen-grpc-java:1.9.0-SNAPSHOT' // CURRENT_GRPC_VERSION
+ }
+ }
+ generateProtoTasks {
+ all().each { task ->
+ task.plugins {
+ javalite {}
+ grpc {
+ // Options added to --grpc_out
+ option 'lite'
+ }
+ }
+ }
+ }
+}
+
+dependencies {
+ compile 'com.android.support:appcompat-v7:25.0.0'
+
+ // You need to build grpc-java to obtain these libraries below.
+ compile 'io.grpc:grpc-okhttp:1.9.0-SNAPSHOT' // CURRENT_GRPC_VERSION
+ compile 'io.grpc:grpc-protobuf-lite:1.9.0-SNAPSHOT' // CURRENT_GRPC_VERSION
+ compile 'io.grpc:grpc-stub:1.9.0-SNAPSHOT' // CURRENT_GRPC_VERSION
+ compile 'javax.annotation:javax.annotation-api:1.2'
+
+ testCompile 'junit:junit:4.12'
+ testCompile 'com.google.truth:truth:0.28'
+ testCompile 'io.grpc:grpc-testing:1.9.0-SNAPSHOT'
+}
diff --git a/examples/android/clientcache/app/proguard-rules.pro b/examples/android/clientcache/app/proguard-rules.pro
new file mode 100644
index 0000000000..1507a52678
--- /dev/null
+++ b/examples/android/clientcache/app/proguard-rules.pro
@@ -0,0 +1,17 @@
+# Add project specific ProGuard rules here.
+# By default, the flags in this file are appended to flags specified
+# in $ANDROID_HOME/tools/proguard/proguard-android.txt
+# You can edit the include path and order by changing the proguardFiles
+# directive in build.gradle.
+#
+# For more details, see
+# http://developer.android.com/guide/developing/tools/proguard.html
+
+# Add any project specific keep options here:
+
+-dontwarn com.google.common.**
+# Ignores: can't find referenced class javax.lang.model.element.Modifier
+-dontwarn com.google.errorprone.annotations.**
+-dontwarn javax.naming.**
+-dontwarn okio.**
+-dontwarn sun.misc.Unsafe
diff --git a/examples/android/clientcache/app/src/main/AndroidManifest.xml b/examples/android/clientcache/app/src/main/AndroidManifest.xml
new file mode 100644
index 0000000000..d31cbd9409
--- /dev/null
+++ b/examples/android/clientcache/app/src/main/AndroidManifest.xml
@@ -0,0 +1,22 @@
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
diff --git a/examples/android/clientcache/app/src/main/java/io/grpc/clientcacheexample/ClientCacheExampleActivity.java b/examples/android/clientcache/app/src/main/java/io/grpc/clientcacheexample/ClientCacheExampleActivity.java
new file mode 100644
index 0000000000..831c1030ac
--- /dev/null
+++ b/examples/android/clientcache/app/src/main/java/io/grpc/clientcacheexample/ClientCacheExampleActivity.java
@@ -0,0 +1,152 @@
+/*
+ * Copyright 2015, gRPC Authors All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.grpc.clientcacheexample;
+
+import android.content.Context;
+import android.os.AsyncTask;
+import android.os.Bundle;
+import android.support.v7.app.AppCompatActivity;
+import android.text.TextUtils;
+import android.text.method.ScrollingMovementMethod;
+import android.util.Log;
+import android.view.View;
+import android.view.inputmethod.InputMethodManager;
+import android.widget.Button;
+import android.widget.CheckBox;
+import android.widget.EditText;
+import android.widget.TextView;
+import io.grpc.CallOptions;
+import io.grpc.Channel;
+import io.grpc.ClientInterceptors;
+import io.grpc.ManagedChannel;
+import io.grpc.ManagedChannelBuilder;
+import io.grpc.MethodDescriptor;
+import io.grpc.examples.helloworld.GreeterGrpc;
+import io.grpc.examples.helloworld.HelloReply;
+import io.grpc.examples.helloworld.HelloRequest;
+import io.grpc.stub.ClientCalls;
+import java.io.PrintWriter;
+import java.io.StringWriter;
+import java.util.concurrent.TimeUnit;
+
+public final class ClientCacheExampleActivity extends AppCompatActivity {
+ private static final int CACHE_SIZE_IN_BYTES = 1 * 1024 * 1024; // 1MB
+ private static final String TAG = "grpcCacheExample";
+ private Button mSendButton;
+ private EditText mHostEdit;
+ private EditText mPortEdit;
+ private EditText mMessageEdit;
+ private TextView mResultText;
+ private CheckBox getCheckBox;
+ private CheckBox noCacheCheckBox;
+ private CheckBox onlyIfCachedCheckBox;
+ private SafeMethodCachingInterceptor.Cache cache;
+
+ @Override
+ protected void onCreate(Bundle savedInstanceState) {
+ super.onCreate(savedInstanceState);
+ setContentView(R.layout.activity_clientcacheexample);
+ mSendButton = (Button) findViewById(R.id.send_button);
+ mHostEdit = (EditText) findViewById(R.id.host_edit_text);
+ mPortEdit = (EditText) findViewById(R.id.port_edit_text);
+ mMessageEdit = (EditText) findViewById(R.id.message_edit_text);
+ getCheckBox = (CheckBox) findViewById(R.id.get_checkbox);
+ noCacheCheckBox = (CheckBox) findViewById(R.id.no_cache_checkbox);
+ onlyIfCachedCheckBox = (CheckBox) findViewById(R.id.only_if_cached_checkbox);
+ mResultText = (TextView) findViewById(R.id.grpc_response_text);
+ mResultText.setMovementMethod(new ScrollingMovementMethod());
+
+ cache = SafeMethodCachingInterceptor.newLruCache(CACHE_SIZE_IN_BYTES);
+ }
+
+ /** Sends RPC. Invoked when app button is pressed. */
+ public void sendMessage(View view) {
+ ((InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE))
+ .hideSoftInputFromWindow(mHostEdit.getWindowToken(), 0);
+ mSendButton.setEnabled(false);
+ new GrpcTask().execute();
+ }
+
+ private class GrpcTask extends AsyncTask {
+ private String host;
+ private String message;
+ private int port;
+ private ManagedChannel channel;
+
+ @Override
+ protected void onPreExecute() {
+ host = mHostEdit.getText().toString();
+ message = mMessageEdit.getText().toString();
+ String portStr = mPortEdit.getText().toString();
+ port = TextUtils.isEmpty(portStr) ? 0 : Integer.valueOf(portStr);
+ mResultText.setText("");
+ }
+
+ @Override
+ protected String doInBackground(Void... nothing) {
+ try {
+ channel = ManagedChannelBuilder.forAddress(host, port).usePlaintext(true).build();
+ Channel channelToUse =
+ ClientInterceptors.intercept(
+ channel, SafeMethodCachingInterceptor.newSafeMethodCachingInterceptor(cache));
+ HelloRequest message = HelloRequest.newBuilder().setName(this.message).build();
+ HelloReply reply;
+ if (getCheckBox.isChecked()) {
+ MethodDescriptor safeCacheableUnaryCallMethod =
+ GreeterGrpc.getSayHelloMethod().toBuilder().setSafe(true).build();
+ CallOptions callOptions = CallOptions.DEFAULT;
+ if (noCacheCheckBox.isChecked()) {
+ callOptions =
+ callOptions.withOption(SafeMethodCachingInterceptor.NO_CACHE_CALL_OPTION, true);
+ }
+ if (onlyIfCachedCheckBox.isChecked()) {
+ callOptions =
+ callOptions.withOption(
+ SafeMethodCachingInterceptor.ONLY_IF_CACHED_CALL_OPTION, true);
+ }
+ reply =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeCacheableUnaryCallMethod, callOptions, message);
+ } else {
+ GreeterGrpc.GreeterBlockingStub stub = GreeterGrpc.newBlockingStub(channelToUse);
+ reply = stub.sayHello(message);
+ }
+ return reply.getMessage();
+ } catch (Exception e) {
+ Log.e(TAG, "RPC failed", e);
+ StringWriter sw = new StringWriter();
+ PrintWriter pw = new PrintWriter(sw);
+ e.printStackTrace(pw);
+ pw.flush();
+ return String.format("Failed... : %n%s", sw);
+ }
+ }
+
+ @Override
+ protected void onPostExecute(String result) {
+ if (channel != null) {
+ try {
+ channel.shutdown().awaitTermination(1, TimeUnit.SECONDS);
+ } catch (InterruptedException e) {
+ Thread.currentThread().interrupt();
+ }
+ }
+ mResultText.setText(result);
+ mSendButton.setEnabled(true);
+ }
+ }
+}
diff --git a/examples/android/clientcache/app/src/main/java/io/grpc/clientcacheexample/SafeMethodCachingInterceptor.java b/examples/android/clientcache/app/src/main/java/io/grpc/clientcacheexample/SafeMethodCachingInterceptor.java
new file mode 100644
index 0000000000..4ae0c01c56
--- /dev/null
+++ b/examples/android/clientcache/app/src/main/java/io/grpc/clientcacheexample/SafeMethodCachingInterceptor.java
@@ -0,0 +1,300 @@
+package io.grpc.clientcacheexample;
+
+import android.util.Log;
+import android.util.LruCache;
+import com.google.common.base.Splitter;
+import com.google.protobuf.MessageLite;
+import io.grpc.CallOptions;
+import io.grpc.Channel;
+import io.grpc.ClientCall;
+import io.grpc.ClientInterceptor;
+import io.grpc.Deadline;
+import io.grpc.ForwardingClientCall;
+import io.grpc.ForwardingClientCallListener;
+import io.grpc.Metadata;
+import io.grpc.MethodDescriptor;
+import io.grpc.Status;
+import java.util.Objects;
+import java.util.concurrent.TimeUnit;
+
+/**
+ * An example of an on-device cache for Android implemented using the {@link ClientInterceptor} API.
+ *
+ *
Client-side cache-control directives are not directly supported. Instead, two call options can
+ * be added to the call: no-cache (always go to the network) or only-if-cached (never use network;
+ * if response is not in cache, the request fails).
+ *
+ *
This interceptor respects the cache-control directives in the server's response: max-age
+ * determines when the cache entry goes stale. no-cache, no-store, and no-transform entirely skip
+ * caching of the response. must-revalidate is ignored, as the cache does not support returning
+ * stale responses.
+ *
+ *
Note: other response headers besides cache-control (such as Expiration, Varies) are ignored by
+ * this implementation.
+ */
+final class SafeMethodCachingInterceptor implements ClientInterceptor {
+ static CallOptions.Key NO_CACHE_CALL_OPTION = CallOptions.Key.of("no-cache", false);
+ static CallOptions.Key ONLY_IF_CACHED_CALL_OPTION =
+ CallOptions.Key.of("only-if-cached", false);
+ private static final String TAG = "grpcCacheExample";
+
+ public static final class Key {
+ private final String fullMethodName;
+ private final MessageLite request;
+
+ public Key(String fullMethodName, MessageLite request) {
+ this.fullMethodName = fullMethodName;
+ this.request = request;
+ }
+
+ @Override
+ public boolean equals(Object object) {
+ if (object instanceof Key) {
+ Key other = (Key) object;
+ return Objects.equals(this.fullMethodName, other.fullMethodName)
+ && Objects.equals(this.request, other.request);
+ }
+ return false;
+ }
+
+ @Override
+ public int hashCode() {
+ return Objects.hash(fullMethodName, request);
+ }
+ }
+
+ public static final class Value {
+ private final MessageLite response;
+ private final Deadline maxAgeDeadline;
+
+ public Value(MessageLite response, Deadline maxAgeDeadline) {
+ this.response = response;
+ this.maxAgeDeadline = maxAgeDeadline;
+ }
+
+ @Override
+ public boolean equals(Object object) {
+ if (object instanceof Value) {
+ Value other = (Value) object;
+ return Objects.equals(this.response, other.response)
+ && Objects.equals(this.maxAgeDeadline, other.maxAgeDeadline);
+ }
+ return false;
+ }
+
+ @Override
+ public int hashCode() {
+ return Objects.hash(response, maxAgeDeadline);
+ }
+ }
+
+ public interface Cache {
+ void put(Key key, Value value);
+
+ Value get(Key key);
+
+ void remove(Key key);
+
+ void clear();
+ }
+
+ /**
+ * Obtain a new cache with a least-recently used eviction policy and the specified size limit. The
+ * backing caching implementation is provided by {@link LruCache}. It is safe for a single cache
+ * to be shared across multiple {@link SafeMethodCachingInterceptor}s without synchronization.
+ */
+ public static Cache newLruCache(final int cacheSizeInBytes) {
+ return new Cache() {
+ private final LruCache lruCache =
+ new LruCache(cacheSizeInBytes) {
+ protected int sizeOf(Key key, Value value) {
+ return value.response.getSerializedSize();
+ }
+ };
+
+ @Override
+ public void put(Key key, Value value) {
+ lruCache.put(key, value);
+ }
+
+ @Override
+ public Value get(Key key) {
+ return lruCache.get(key);
+ }
+
+ @Override
+ public void remove(Key key) {
+ lruCache.remove(key);
+ }
+
+ @Override
+ public void clear() {
+ lruCache.evictAll();
+ }
+ };
+ }
+
+ public static SafeMethodCachingInterceptor newSafeMethodCachingInterceptor(Cache cache) {
+ return newSafeMethodCachingInterceptor(cache, DEFAULT_MAX_AGE_SECONDS);
+ }
+
+ public static SafeMethodCachingInterceptor newSafeMethodCachingInterceptor(
+ Cache cache, int defaultMaxAge) {
+ return new SafeMethodCachingInterceptor(cache, defaultMaxAge);
+ }
+
+ private static int DEFAULT_MAX_AGE_SECONDS = 3600;
+
+ private static final Metadata.Key CACHE_CONTROL_KEY =
+ Metadata.Key.of("cache-control", Metadata.ASCII_STRING_MARSHALLER);
+
+ private static final Splitter CACHE_CONTROL_SPLITTER =
+ Splitter.on(',').trimResults().omitEmptyStrings();
+
+ private final Cache internalCache;
+ private final int defaultMaxAge;
+
+ private SafeMethodCachingInterceptor(Cache cache, int defaultMaxAge) {
+ this.internalCache = cache;
+ this.defaultMaxAge = defaultMaxAge;
+ }
+
+ @Override
+ public ClientCall interceptCall(
+ final MethodDescriptor method, final CallOptions callOptions, Channel next) {
+ // Currently only unary methods can be marked safe, but check anyways.
+ if (!method.isSafe() || method.getType() != MethodDescriptor.MethodType.UNARY) {
+ return next.newCall(method, callOptions);
+ }
+
+ final String fullMethodName = method.getFullMethodName();
+
+ return new ForwardingClientCall.SimpleForwardingClientCall(
+ next.newCall(method, callOptions)) {
+ private Listener interceptedListener;
+ private Key requestKey;
+ private boolean cacheResponse = true;
+ private volatile String cacheOptionsErrorMsg;
+
+ @Override
+ public void start(Listener responseListener, Metadata headers) {
+ interceptedListener =
+ new ForwardingClientCallListener.SimpleForwardingClientCallListener(
+ responseListener) {
+ private Deadline deadline;
+ private int maxAge = -1;
+
+ @Override
+ public void onHeaders(Metadata headers) {
+ Iterable cacheControlHeaders = headers.getAll(CACHE_CONTROL_KEY);
+ if (cacheResponse && cacheControlHeaders != null) {
+ for (String cacheControlHeader : cacheControlHeaders) {
+ for (String directive : CACHE_CONTROL_SPLITTER.split(cacheControlHeader)) {
+ if (directive.equalsIgnoreCase("no-cache")) {
+ cacheResponse = false;
+ break;
+ } else if (directive.equalsIgnoreCase("no-store")) {
+ cacheResponse = false;
+ break;
+ } else if (directive.equalsIgnoreCase("no-transform")) {
+ cacheResponse = false;
+ break;
+ } else if (directive.toLowerCase().startsWith("max-age")) {
+ String[] parts = directive.split("=");
+ if (parts.length == 2) {
+ try {
+ maxAge = Integer.parseInt(parts[1]);
+ } catch (NumberFormatException e) {
+ Log.e(TAG, "max-age directive failed to parse", e);
+ continue;
+ }
+ }
+ }
+ }
+ }
+ }
+ if (cacheResponse) {
+ if (maxAge > -1) {
+ deadline = Deadline.after(maxAge, TimeUnit.SECONDS);
+ } else {
+ deadline = Deadline.after(defaultMaxAge, TimeUnit.SECONDS);
+ }
+ }
+ super.onHeaders(headers);
+ }
+
+ @Override
+ public void onMessage(RespT message) {
+ if (cacheResponse && !deadline.isExpired()) {
+ Value value = new Value((MessageLite) message, deadline);
+ internalCache.put(requestKey, value);
+ }
+ super.onMessage(message);
+ }
+
+ @Override
+ public void onClose(Status status, Metadata trailers) {
+ if (cacheOptionsErrorMsg != null) {
+ // UNAVAILABLE is the canonical gRPC mapping for HTTP response code 504 (as used
+ // by the built-in Android HTTP request cache).
+ super.onClose(
+ Status.UNAVAILABLE.withDescription(cacheOptionsErrorMsg), new Metadata());
+ } else {
+ super.onClose(status, trailers);
+ }
+ }
+ };
+ delegate().start(interceptedListener, headers);
+ }
+
+ @Override
+ public void sendMessage(ReqT message) {
+ boolean noCache = callOptions.getOption(NO_CACHE_CALL_OPTION);
+ boolean onlyIfCached = callOptions.getOption(ONLY_IF_CACHED_CALL_OPTION);
+
+ if (noCache) {
+ if (onlyIfCached) {
+ cacheOptionsErrorMsg = "Unsatisfiable Request (no-cache and only-if-cached conflict)";
+ super.cancel(cacheOptionsErrorMsg, null);
+ return;
+ }
+ cacheResponse = false;
+ super.sendMessage(message);
+ return;
+ }
+
+ // Check the cache
+ requestKey = new Key(fullMethodName, (MessageLite) message);
+ Value cachedResponse = internalCache.get(requestKey);
+ if (cachedResponse != null) {
+ if (cachedResponse.maxAgeDeadline.isExpired()) {
+ internalCache.remove(requestKey);
+ } else {
+ cacheResponse = false; // already cached
+ interceptedListener.onMessage((RespT) cachedResponse.response);
+ Metadata metadata = new Metadata();
+ interceptedListener.onClose(Status.OK, metadata);
+ return;
+ }
+ }
+
+ if (onlyIfCached) {
+ cacheOptionsErrorMsg =
+ "Unsatisfiable Request (only-if-cached set, but value not in cache)";
+ super.cancel(cacheOptionsErrorMsg, null);
+ return;
+ }
+ super.sendMessage(message);
+ }
+
+ @Override
+ public void halfClose() {
+ if (cacheOptionsErrorMsg != null) {
+ // already canceled
+ return;
+ }
+ super.halfClose();
+ }
+ };
+ }
+}
diff --git a/examples/android/clientcache/app/src/main/proto/helloworld.proto b/examples/android/clientcache/app/src/main/proto/helloworld.proto
new file mode 100644
index 0000000000..7469e1e47d
--- /dev/null
+++ b/examples/android/clientcache/app/src/main/proto/helloworld.proto
@@ -0,0 +1,45 @@
+// Copyright 2015, gRPC Authors
+// All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+syntax = "proto3";
+
+option java_multiple_files = true;
+option java_package = "io.grpc.examples.helloworld";
+option java_outer_classname = "HelloWorldProto";
+option objc_class_prefix = "HLW";
+
+package helloworld;
+
+// The greeting service definition.
+service Greeter {
+ // Sends a greeting
+ rpc SayHello (HelloRequest) returns (HelloReply) {}
+
+ rpc SayAnotherHello (HelloRequest) returns (HelloReply) {}
+
+}
+
+service AnotherGreeter {
+ rpc SayHello (HelloRequest) returns (HelloReply) {}
+}
+
+// The request message containing the user's name.
+message HelloRequest {
+ string name = 1;
+}
+
+// The response message containing the greetings
+message HelloReply {
+ string message = 1;
+}
diff --git a/examples/android/clientcache/app/src/main/res/layout/activity_clientcacheexample.xml b/examples/android/clientcache/app/src/main/res/layout/activity_clientcacheexample.xml
new file mode 100644
index 0000000000..2e48e8a273
--- /dev/null
+++ b/examples/android/clientcache/app/src/main/res/layout/activity_clientcacheexample.xml
@@ -0,0 +1,73 @@
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
diff --git a/examples/android/clientcache/app/src/main/res/mipmap-hdpi/ic_launcher.png b/examples/android/clientcache/app/src/main/res/mipmap-hdpi/ic_launcher.png
new file mode 100644
index 0000000000..cde69bccce
Binary files /dev/null and b/examples/android/clientcache/app/src/main/res/mipmap-hdpi/ic_launcher.png differ
diff --git a/examples/android/clientcache/app/src/main/res/mipmap-mdpi/ic_launcher.png b/examples/android/clientcache/app/src/main/res/mipmap-mdpi/ic_launcher.png
new file mode 100644
index 0000000000..c133a0cbd3
Binary files /dev/null and b/examples/android/clientcache/app/src/main/res/mipmap-mdpi/ic_launcher.png differ
diff --git a/examples/android/clientcache/app/src/main/res/mipmap-xhdpi/ic_launcher.png b/examples/android/clientcache/app/src/main/res/mipmap-xhdpi/ic_launcher.png
new file mode 100644
index 0000000000..bfa42f0e7b
Binary files /dev/null and b/examples/android/clientcache/app/src/main/res/mipmap-xhdpi/ic_launcher.png differ
diff --git a/examples/android/clientcache/app/src/main/res/mipmap-xxhdpi/ic_launcher.png b/examples/android/clientcache/app/src/main/res/mipmap-xxhdpi/ic_launcher.png
new file mode 100644
index 0000000000..324e72cdd7
Binary files /dev/null and b/examples/android/clientcache/app/src/main/res/mipmap-xxhdpi/ic_launcher.png differ
diff --git a/examples/android/clientcache/app/src/main/res/values/strings.xml b/examples/android/clientcache/app/src/main/res/values/strings.xml
new file mode 100644
index 0000000000..0f8d82d952
--- /dev/null
+++ b/examples/android/clientcache/app/src/main/res/values/strings.xml
@@ -0,0 +1,3 @@
+
+ GrpcClientCacheExample
+
diff --git a/examples/android/clientcache/app/src/test/java/io/grpc/clientcacheexample/SafeMethodCachingInterceptorTest.java b/examples/android/clientcache/app/src/test/java/io/grpc/clientcacheexample/SafeMethodCachingInterceptorTest.java
new file mode 100644
index 0000000000..4fd5bdb0c8
--- /dev/null
+++ b/examples/android/clientcache/app/src/test/java/io/grpc/clientcacheexample/SafeMethodCachingInterceptorTest.java
@@ -0,0 +1,557 @@
+package io.grpc.clientcacheexample;
+
+import com.google.common.truth.Truth;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotEquals;
+import static org.junit.Assert.assertSame;
+import static org.junit.Assert.fail;
+
+import io.grpc.CallOptions;
+import io.grpc.Channel;
+import io.grpc.ClientInterceptors;
+import io.grpc.ForwardingServerCall;
+import io.grpc.ManagedChannel;
+import io.grpc.Metadata;
+import io.grpc.MethodDescriptor;
+import io.grpc.ServerCall;
+import io.grpc.ServerCallHandler;
+import io.grpc.ServerInterceptor;
+import io.grpc.ServerInterceptors;
+import io.grpc.Status;
+import io.grpc.StatusRuntimeException;
+import io.grpc.examples.helloworld.AnotherGreeterGrpc;
+import io.grpc.examples.helloworld.GreeterGrpc;
+import io.grpc.examples.helloworld.HelloReply;
+import io.grpc.examples.helloworld.HelloRequest;
+import io.grpc.stub.ClientCalls;
+import io.grpc.stub.StreamObserver;
+import io.grpc.testing.GrpcServerRule;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.concurrent.TimeUnit;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Rule;
+import org.junit.Test;
+
+public class SafeMethodCachingInterceptorTest {
+ private static final Metadata.Key CACHE_CONTROL_METADATA_KEY =
+ Metadata.Key.of("cache-control", Metadata.ASCII_STRING_MARSHALLER);
+
+ @Rule public final GrpcServerRule grpcServerRule = new GrpcServerRule().directExecutor();
+
+ private final GreeterGrpc.GreeterImplBase greeterServiceImpl =
+ new GreeterGrpc.GreeterImplBase() {
+ private int count = 1;
+
+ @Override
+ public void sayHello(HelloRequest req, StreamObserver responseObserver) {
+ HelloReply reply =
+ HelloReply.newBuilder().setMessage("Hello " + req.getName() + " " + count++).build();
+ responseObserver.onNext(reply);
+ responseObserver.onCompleted();
+ }
+
+ @Override
+ public void sayAnotherHello(HelloRequest req, StreamObserver responseObserver) {
+ HelloReply reply =
+ HelloReply.newBuilder()
+ .setMessage("Hello again " + req.getName() + " " + count++)
+ .build();
+ responseObserver.onNext(reply);
+ responseObserver.onCompleted();
+ }
+ };
+
+ private final AnotherGreeterGrpc.AnotherGreeterImplBase anotherGreeterServiceImpl =
+ new AnotherGreeterGrpc.AnotherGreeterImplBase() {
+ private int count = 1;
+
+ @Override
+ public void sayHello(HelloRequest req, StreamObserver responseObserver) {
+ HelloReply reply =
+ HelloReply.newBuilder().setMessage("Hey " + req.getName() + " " + count++).build();
+ responseObserver.onNext(reply);
+ responseObserver.onCompleted();
+ }
+ };
+
+ private final List cacheControlDirectives = new ArrayList();
+ private ServerInterceptor injectCacheControlInterceptor =
+ new ServerInterceptor() {
+ @Override
+ public ServerCall.Listener interceptCall(
+ ServerCall call,
+ final Metadata requestHeaders,
+ ServerCallHandler next) {
+ return next.startCall(
+ new ForwardingServerCall.SimpleForwardingServerCall(call) {
+ @Override
+ public void sendHeaders(Metadata headers) {
+ for (String cacheControlDirective : cacheControlDirectives) {
+ headers.put(CACHE_CONTROL_METADATA_KEY, cacheControlDirective);
+ }
+ super.sendHeaders(headers);
+ }
+ },
+ requestHeaders);
+ }
+ };
+
+ private final HelloRequest message = HelloRequest.newBuilder().setName("Test Name").build();
+ private final MethodDescriptor safeGreeterSayHelloMethod =
+ GreeterGrpc.getSayHelloMethod().toBuilder().setSafe(true).build();
+ private final TestCache cache = new TestCache();
+
+ private ManagedChannel baseChannel;
+ private Channel channelToUse;
+
+ @Before
+ public void setUp() throws Exception {
+ grpcServerRule
+ .getServiceRegistry()
+ .addService(
+ ServerInterceptors.intercept(greeterServiceImpl, injectCacheControlInterceptor));
+ grpcServerRule.getServiceRegistry().addService(anotherGreeterServiceImpl);
+ baseChannel = grpcServerRule.getChannel();
+
+ SafeMethodCachingInterceptor interceptor =
+ SafeMethodCachingInterceptor.newSafeMethodCachingInterceptor(cache);
+
+ channelToUse = ClientInterceptors.intercept(baseChannel, interceptor);
+ }
+
+ @After
+ public void tearDown() {
+ baseChannel.shutdown();
+ }
+
+ @Test
+ public void safeCallsAreCached() {
+ HelloReply reply1 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+ HelloReply reply2 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+
+ assertSame(reply1, reply2);
+ }
+
+ @Test
+ public void safeCallsAreCachedWithCopiedMethodDescriptor() {
+ HelloReply reply1 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+ HelloReply reply2 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse,
+ safeGreeterSayHelloMethod.toBuilder().build(),
+ CallOptions.DEFAULT,
+ message);
+
+ assertSame(reply1, reply2);
+ }
+
+ @Test
+ public void requestWithNoCacheOptionSkipsCache() {
+ HelloReply reply1 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+ HelloReply reply2 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse,
+ safeGreeterSayHelloMethod,
+ CallOptions.DEFAULT.withOption(SafeMethodCachingInterceptor.NO_CACHE_CALL_OPTION, true),
+ message);
+ HelloReply reply3 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+
+ assertNotEquals(reply1, reply2);
+ assertSame(reply1, reply3);
+ }
+
+ @Test
+ public void requestWithOnlyIfCachedOption_unavailableIfNotInCache() {
+ try {
+ ClientCalls.blockingUnaryCall(
+ channelToUse,
+ safeGreeterSayHelloMethod,
+ CallOptions.DEFAULT.withOption(
+ SafeMethodCachingInterceptor.ONLY_IF_CACHED_CALL_OPTION, true),
+ message);
+ fail("Expected call to fail");
+ } catch (StatusRuntimeException sre) {
+ assertEquals(Status.UNAVAILABLE.getCode(), sre.getStatus().getCode());
+ assertEquals(
+ "Unsatisfiable Request (only-if-cached set, but value not in cache)",
+ sre.getStatus().getDescription());
+ }
+ }
+
+ @Test
+ public void requestWithOnlyIfCachedOption_usesCache() {
+ HelloReply reply1 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+ HelloReply reply2 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse,
+ safeGreeterSayHelloMethod,
+ CallOptions.DEFAULT.withOption(
+ SafeMethodCachingInterceptor.ONLY_IF_CACHED_CALL_OPTION, true),
+ message);
+
+ assertSame(reply1, reply2);
+ }
+
+ @Test
+ public void requestWithNoCacheAndOnlyIfCached_fails() {
+ try {
+ ClientCalls.blockingUnaryCall(
+ channelToUse,
+ safeGreeterSayHelloMethod,
+ CallOptions.DEFAULT
+ .withOption(SafeMethodCachingInterceptor.NO_CACHE_CALL_OPTION, true)
+ .withOption(SafeMethodCachingInterceptor.ONLY_IF_CACHED_CALL_OPTION, true),
+ message);
+ fail("Expected call to fail");
+ } catch (StatusRuntimeException sre) {
+ assertEquals(Status.UNAVAILABLE.getCode(), sre.getStatus().getCode());
+ assertEquals(
+ "Unsatisfiable Request (no-cache and only-if-cached conflict)",
+ sre.getStatus().getDescription());
+ }
+ }
+
+ @Test
+ public void responseNoCacheDirective_notCached() throws Exception {
+ cacheControlDirectives.add("no-cache");
+
+ HelloReply reply1 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+ HelloReply reply2 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+
+ assertNotEquals(reply1, reply2);
+ assertNotEquals(reply1, reply2);
+ Truth.assertThat(cache.internalCache).isEmpty();
+ Truth.assertThat(cache.removedKeys).isEmpty();
+ }
+
+ @Test
+ public void responseNoStoreDirective_notCached() throws Exception {
+ cacheControlDirectives.add("no-store");
+
+ HelloReply reply1 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+ HelloReply reply2 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+
+ assertNotEquals(reply1, reply2);
+ Truth.assertThat(cache.internalCache).isEmpty();
+ Truth.assertThat(cache.removedKeys).isEmpty();
+ }
+
+ @Test
+ public void responseNoTransformDirective_notCached() throws Exception {
+ cacheControlDirectives.add("no-transform");
+
+ HelloReply reply1 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+ HelloReply reply2 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+
+ assertNotEquals(reply1, reply2);
+ Truth.assertThat(cache.internalCache).isEmpty();
+ Truth.assertThat(cache.removedKeys).isEmpty();
+ }
+
+ @Test
+ public void responseMustRevalidateDirective_isIgnored() throws Exception {
+ cacheControlDirectives.add("must-revalidate");
+
+ HelloReply reply1 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+ HelloReply reply2 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+
+ assertSame(reply1, reply2);
+ }
+
+ @Test
+ public void responseMaxAge_caseInsensitive() throws Exception {
+ cacheControlDirectives.add("MaX-aGe=0");
+
+ HelloReply reply1 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+ HelloReply reply2 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+
+ assertNotEquals(reply1, reply2);
+ Truth.assertThat(cache.internalCache).isEmpty();
+ Truth.assertThat(cache.removedKeys).isEmpty();
+ }
+
+ @Test
+ public void responseNoCache_caseInsensitive() throws Exception {
+ cacheControlDirectives.add("No-CaCHe");
+
+ HelloReply reply1 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+ HelloReply reply2 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+
+ assertNotEquals(reply1, reply2);
+ Truth.assertThat(cache.internalCache).isEmpty();
+ Truth.assertThat(cache.removedKeys).isEmpty();
+ }
+
+ @Test
+ public void combinedResponseCacheControlDirectives_parsesWithoutError() throws Exception {
+ cacheControlDirectives.add("max-age=1,no-store , no-cache");
+
+ HelloReply reply1 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+ HelloReply reply2 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+
+ assertNotEquals(reply1, reply2);
+ Truth.assertThat(cache.internalCache).isEmpty();
+ Truth.assertThat(cache.removedKeys).isEmpty();
+ }
+
+ @Test
+ public void separateResponseCacheControlDirectives_parsesWithoutError() throws Exception {
+ cacheControlDirectives.add("max-age=1");
+ cacheControlDirectives.add("no-store , no-cache");
+
+ HelloReply reply1 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+ HelloReply reply2 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+
+ assertNotEquals(reply1, reply2);
+ Truth.assertThat(cache.internalCache).isEmpty();
+ Truth.assertThat(cache.removedKeys).isEmpty();
+ }
+
+ @Test
+ public void afterResponseMaxAge_cacheEntryInvalidated() throws Exception {
+ cacheControlDirectives.add("max-age=1");
+
+ HelloReply reply1 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+ HelloReply reply2 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+ assertSame(reply1, reply2);
+
+ // Wait for cache entry to expire
+ sleepAtLeast(1001);
+
+ assertNotEquals(
+ reply1,
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message));
+ Truth.assertThat(cache.removedKeys).hasSize(1);
+ assertEquals(
+ new SafeMethodCachingInterceptor.Key(
+ GreeterGrpc.getSayHelloMethod().getFullMethodName(), message),
+ cache.removedKeys.get(0));
+ }
+
+ @Test
+ public void invalidResponseMaxAge_usesDefault() throws Exception {
+ SafeMethodCachingInterceptor interceptorWithCustomMaxAge =
+ SafeMethodCachingInterceptor.newSafeMethodCachingInterceptor(cache, 1);
+ channelToUse = ClientInterceptors.intercept(baseChannel, interceptorWithCustomMaxAge);
+ cacheControlDirectives.add("max-age=-10");
+
+ HelloReply reply1 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+ HelloReply reply2 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+ assertEquals(reply1, reply2);
+
+ // Wait for cache entry to expire
+ sleepAtLeast(1001);
+
+ assertNotEquals(
+ reply1,
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message));
+ Truth.assertThat(cache.removedKeys).hasSize(1);
+ assertEquals(
+ new SafeMethodCachingInterceptor.Key(
+ GreeterGrpc.getSayHelloMethod().getFullMethodName(), message),
+ cache.removedKeys.get(0));
+ }
+
+ @Test
+ public void responseMaxAgeZero_notAddedToCache() throws Exception {
+ cacheControlDirectives.add("max-age=0");
+
+ HelloReply reply1 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+ HelloReply reply2 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+
+ assertNotEquals(reply1, reply2);
+ Truth.assertThat(cache.internalCache).isEmpty();
+ Truth.assertThat(cache.removedKeys).isEmpty();
+ }
+
+ @Test
+ public void cacheHit_doesNotResetExpiration() throws Exception {
+ cacheControlDirectives.add("max-age=1");
+
+ HelloReply reply1 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+ HelloReply reply2 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+
+ sleepAtLeast(1001);
+
+ HelloReply reply3 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+
+ assertSame(reply1, reply2);
+ assertNotEquals(reply1, reply3);
+ Truth.assertThat(cache.internalCache).hasSize(1);
+ Truth.assertThat(cache.removedKeys).hasSize(1);
+ }
+
+ @Test
+ public void afterDefaultMaxAge_cacheEntryInvalidated() throws Exception {
+ SafeMethodCachingInterceptor interceptorWithCustomMaxAge =
+ SafeMethodCachingInterceptor.newSafeMethodCachingInterceptor(cache, 1);
+ channelToUse = ClientInterceptors.intercept(baseChannel, interceptorWithCustomMaxAge);
+
+ HelloReply reply1 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+ HelloReply reply2 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+ assertSame(reply1, reply2);
+
+ // Wait for cache entry to expire
+ sleepAtLeast(1001);
+
+ assertNotEquals(
+ reply1,
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message));
+ Truth.assertThat(cache.removedKeys).hasSize(1);
+ assertEquals(
+ new SafeMethodCachingInterceptor.Key(
+ GreeterGrpc.getSayHelloMethod().getFullMethodName(), message),
+ cache.removedKeys.get(0));
+ }
+
+ @Test
+ public void unsafeCallsAreNotCached() {
+ GreeterGrpc.GreeterBlockingStub stub = GreeterGrpc.newBlockingStub(channelToUse);
+
+ HelloReply reply1 = stub.sayHello(message);
+ HelloReply reply2 = stub.sayHello(message);
+
+ assertNotEquals(reply1, reply2);
+ }
+
+ @Test
+ public void differentMethodCallsAreNotConflated() {
+ MethodDescriptor anotherSafeMethod =
+ GreeterGrpc.getSayAnotherHelloMethod().toBuilder().setSafe(true).build();
+
+ HelloReply reply1 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+ HelloReply reply2 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, anotherSafeMethod, CallOptions.DEFAULT, message);
+
+ assertNotEquals(reply1, reply2);
+ }
+
+ @Test
+ public void differentServiceCallsAreNotConflated() {
+ MethodDescriptor anotherSafeMethod =
+ AnotherGreeterGrpc.getSayHelloMethod().toBuilder().setSafe(true).build();
+
+ HelloReply reply1 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, safeGreeterSayHelloMethod, CallOptions.DEFAULT, message);
+ HelloReply reply2 =
+ ClientCalls.blockingUnaryCall(
+ channelToUse, anotherSafeMethod, CallOptions.DEFAULT, message);
+
+ assertNotEquals(reply1, reply2);
+ }
+
+ private static void sleepAtLeast(long millis) throws InterruptedException {
+ long delay = TimeUnit.MILLISECONDS.toNanos(millis);
+ long end = System.nanoTime() + delay;
+ while (delay > 0) {
+ TimeUnit.NANOSECONDS.sleep(delay);
+ delay = end - System.nanoTime();
+ }
+ }
+
+ private static class TestCache implements SafeMethodCachingInterceptor.Cache {
+ private Map
+ internalCache =
+ new HashMap();
+ private List removedKeys =
+ new ArrayList();
+
+ @Override
+ public void put(
+ SafeMethodCachingInterceptor.Key key, SafeMethodCachingInterceptor.Value value) {
+ internalCache.put(key, value);
+ }
+
+ @Override
+ public SafeMethodCachingInterceptor.Value get(SafeMethodCachingInterceptor.Key key) {
+ return internalCache.get(key);
+ }
+
+ @Override
+ public void remove(SafeMethodCachingInterceptor.Key key) {
+ removedKeys.add(key);
+ internalCache.remove(key);
+ }
+
+ @Override
+ public void clear() {}
+ }
+}
diff --git a/examples/android/clientcache/build.gradle b/examples/android/clientcache/build.gradle
new file mode 100644
index 0000000000..be0b49fe99
--- /dev/null
+++ b/examples/android/clientcache/build.gradle
@@ -0,0 +1,21 @@
+// Top-level build file where you can add configuration options common to all sub-projects/modules.
+
+buildscript {
+ repositories {
+ jcenter()
+ }
+ dependencies {
+ classpath 'com.android.tools.build:gradle:2.3.1'
+ classpath "com.google.protobuf:protobuf-gradle-plugin:0.8.1"
+
+ // NOTE: Do not place your application dependencies here; they belong
+ // in the individual module build.gradle files
+ }
+}
+
+allprojects {
+ repositories {
+ jcenter()
+ mavenLocal()
+ }
+}
diff --git a/examples/android/clientcache/gradle/wrapper/gradle-wrapper.jar b/examples/android/clientcache/gradle/wrapper/gradle-wrapper.jar
new file mode 100644
index 0000000000..36823b7ec6
Binary files /dev/null and b/examples/android/clientcache/gradle/wrapper/gradle-wrapper.jar differ
diff --git a/examples/android/clientcache/gradle/wrapper/gradle-wrapper.properties b/examples/android/clientcache/gradle/wrapper/gradle-wrapper.properties
new file mode 100644
index 0000000000..37c7766f30
--- /dev/null
+++ b/examples/android/clientcache/gradle/wrapper/gradle-wrapper.properties
@@ -0,0 +1,6 @@
+#Tue Jul 11 13:59:44 PDT 2017
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-4.0.1-bin.zip
diff --git a/examples/android/clientcache/gradlew b/examples/android/clientcache/gradlew
new file mode 100755
index 0000000000..cccdd3d517
--- /dev/null
+++ b/examples/android/clientcache/gradlew
@@ -0,0 +1,172 @@
+#!/usr/bin/env sh
+
+##############################################################################
+##
+## Gradle start up script for UN*X
+##
+##############################################################################
+
+# Attempt to set APP_HOME
+# Resolve links: $0 may be a link
+PRG="$0"
+# Need this for relative symlinks.
+while [ -h "$PRG" ] ; do
+ ls=`ls -ld "$PRG"`
+ link=`expr "$ls" : '.*-> \(.*\)$'`
+ if expr "$link" : '/.*' > /dev/null; then
+ PRG="$link"
+ else
+ PRG=`dirname "$PRG"`"/$link"
+ fi
+done
+SAVED="`pwd`"
+cd "`dirname \"$PRG\"`/" >/dev/null
+APP_HOME="`pwd -P`"
+cd "$SAVED" >/dev/null
+
+APP_NAME="Gradle"
+APP_BASE_NAME=`basename "$0"`
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS=""
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD="maximum"
+
+warn () {
+ echo "$*"
+}
+
+die () {
+ echo
+ echo "$*"
+ echo
+ exit 1
+}
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "`uname`" in
+ CYGWIN* )
+ cygwin=true
+ ;;
+ Darwin* )
+ darwin=true
+ ;;
+ MINGW* )
+ msys=true
+ ;;
+ NONSTOP* )
+ nonstop=true
+ ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+ if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+ # IBM's JDK on AIX uses strange locations for the executables
+ JAVACMD="$JAVA_HOME/jre/sh/java"
+ else
+ JAVACMD="$JAVA_HOME/bin/java"
+ fi
+ if [ ! -x "$JAVACMD" ] ; then
+ die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+ fi
+else
+ JAVACMD="java"
+ which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if [ "$cygwin" = "false" -a "$darwin" = "false" -a "$nonstop" = "false" ] ; then
+ MAX_FD_LIMIT=`ulimit -H -n`
+ if [ $? -eq 0 ] ; then
+ if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then
+ MAX_FD="$MAX_FD_LIMIT"
+ fi
+ ulimit -n $MAX_FD
+ if [ $? -ne 0 ] ; then
+ warn "Could not set maximum file descriptor limit: $MAX_FD"
+ fi
+ else
+ warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT"
+ fi
+fi
+
+# For Darwin, add options to specify how the application appears in the dock
+if $darwin; then
+ GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\""
+fi
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin ; then
+ APP_HOME=`cygpath --path --mixed "$APP_HOME"`
+ CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
+ JAVACMD=`cygpath --unix "$JAVACMD"`
+
+ # We build the pattern for arguments to be converted via cygpath
+ ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null`
+ SEP=""
+ for dir in $ROOTDIRSRAW ; do
+ ROOTDIRS="$ROOTDIRS$SEP$dir"
+ SEP="|"
+ done
+ OURCYGPATTERN="(^($ROOTDIRS))"
+ # Add a user-defined pattern to the cygpath arguments
+ if [ "$GRADLE_CYGPATTERN" != "" ] ; then
+ OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)"
+ fi
+ # Now convert the arguments - kludge to limit ourselves to /bin/sh
+ i=0
+ for arg in "$@" ; do
+ CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -`
+ CHECK2=`echo "$arg"|egrep -c "^-"` ### Determine if an option
+
+ if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then ### Added a condition
+ eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"`
+ else
+ eval `echo args$i`="\"$arg\""
+ fi
+ i=$((i+1))
+ done
+ case $i in
+ (0) set -- ;;
+ (1) set -- "$args0" ;;
+ (2) set -- "$args0" "$args1" ;;
+ (3) set -- "$args0" "$args1" "$args2" ;;
+ (4) set -- "$args0" "$args1" "$args2" "$args3" ;;
+ (5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
+ (6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
+ (7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
+ (8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
+ (9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
+ esac
+fi
+
+# Escape application args
+save () {
+ for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done
+ echo " "
+}
+APP_ARGS=$(save "$@")
+
+# Collect all arguments for the java command, following the shell quoting and substitution rules
+eval set -- $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS "\"-Dorg.gradle.appname=$APP_BASE_NAME\"" -classpath "\"$CLASSPATH\"" org.gradle.wrapper.GradleWrapperMain "$APP_ARGS"
+
+# by default we should be in the correct project dir, but when run from Finder on Mac, the cwd is wrong
+if [ "$(uname)" = "Darwin" ] && [ "$HOME" = "$PWD" ]; then
+ cd "$(dirname "$0")"
+fi
+
+exec "$JAVACMD" "$@"
diff --git a/examples/android/clientcache/gradlew.bat b/examples/android/clientcache/gradlew.bat
new file mode 100644
index 0000000000..e95643d6a2
--- /dev/null
+++ b/examples/android/clientcache/gradlew.bat
@@ -0,0 +1,84 @@
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS=
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto init
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto init
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:init
+@rem Get command-line arguments, handling Windows variants
+
+if not "%OS%" == "Windows_NT" goto win9xME_args
+
+:win9xME_args
+@rem Slurp the command line arguments.
+set CMD_LINE_ARGS=
+set _SKIP=2
+
+:win9xME_args_slurp
+if "x%~1" == "x" goto execute
+
+set CMD_LINE_ARGS=%*
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS%
+
+:end
+@rem End local scope for the variables with windows NT shell
+if "%ERRORLEVEL%"=="0" goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+if not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+exit /b 1
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega
diff --git a/examples/android/clientcache/settings.gradle b/examples/android/clientcache/settings.gradle
new file mode 100644
index 0000000000..e7b4def49c
--- /dev/null
+++ b/examples/android/clientcache/settings.gradle
@@ -0,0 +1 @@
+include ':app'