Merge branch 'grpc:master' into grpc-uri-xds

Author: jdcormie

MODULE.bazel

@@ -1,6 +1,6 @@
 module(
     name = "grpc-java",
-    version = "1.80.0-SNAPSHOT",  # CURRENT_GRPC_VERSION
+    version = "1.81.0-SNAPSHOT",  # CURRENT_GRPC_VERSION
     compatibility_level = 0,
     repo_name = "io_grpc_grpc_java",
 )

README.md

@@ -20,7 +20,7 @@ gRPC-Java - An RPC library and framework
 Supported Platforms
 -------------------
 
-gRPC-Java supports Java 8 and later. Android minSdkVersion 21 (Lollipop) and
+gRPC-Java supports Java 8 and later. Android minSdkVersion 23 (Marshmallow) and
 later are supported with [Java 8 language desugaring][android-java-8].
 
 TLS usage on Android typically requires Play Services Dynamic Security Provider.

android/build.gradle

@@ -14,7 +14,7 @@ android {
     }
     compileSdkVersion 34
     defaultConfig {
-        minSdkVersion 22
+        minSdkVersion 23
         targetSdkVersion 33
         versionCode 1
         versionName "1.0"

api/src/main/java/io/grpc/InternalServiceProviders.java

@@ -17,7 +17,9 @@
 package io.grpc;
 
 import com.google.common.annotations.VisibleForTesting;
+import java.util.Iterator;
 import java.util.List;
+import java.util.ServiceLoader;
 
 @Internal
 public final class InternalServiceProviders {
@@ -27,12 +29,28 @@ private InternalServiceProviders() {
   /**
    * Accessor for method.
    */
+  @Deprecated
   public static <T> List<T> loadAll(
       Class<T> klass,
       Iterable<Class<?>> hardCodedClasses,
       ClassLoader classLoader,
       PriorityAccessor<T> priorityAccessor) {
-    return ServiceProviders.loadAll(klass, hardCodedClasses, classLoader, priorityAccessor);
+    return loadAll(
+        klass,
+        ServiceLoader.load(klass, classLoader).iterator(),
+        () -> hardCodedClasses,
+        priorityAccessor);
+  }
+
+  /**
+   * Accessor for method.
+   */
+  public static <T> List<T> loadAll(
+      Class<T> klass,
+      Iterator<T> serviceLoader,
+      Supplier<Iterable<Class<?>>> hardCodedClasses,
+      PriorityAccessor<T> priorityAccessor) {
+    return ServiceProviders.loadAll(klass, serviceLoader, hardCodedClasses::get, priorityAccessor);
   }
 
   /**
@@ -60,4 +78,8 @@ public static boolean isAndroid(ClassLoader cl) {
   }
 
   public interface PriorityAccessor<T> extends ServiceProviders.PriorityAccessor<T> {}
+
+  public interface Supplier<T> {
+    T get();
+  }
 }

api/src/main/java/io/grpc/LoadBalancer.java

@@ -632,6 +632,8 @@ private PickResult(
      *                            stream is created at all in some cases.
      * @since 1.3.0
      */
+    // TODO(shivaspeaks): Need to deprecate old APIs and create new ones, 
+    // per https://github.com/grpc/grpc-java/issues/12662.
     public static PickResult withSubchannel(
         Subchannel subchannel, @Nullable ClientStreamTracer.Factory streamTracerFactory) {
       return new PickResult(
@@ -661,6 +663,28 @@ public static PickResult withSubchannel(Subchannel subchannel) {
       return withSubchannel(subchannel, null);
     }
 
+    /**
+     * Creates a new {@code PickResult} with the given {@code subchannel},
+     * but retains all other properties from this {@code PickResult}.
+     *
+     * @since 1.80.0
+     */
+    public PickResult copyWithSubchannel(Subchannel subchannel) {
+      return new PickResult(checkNotNull(subchannel, "subchannel"), streamTracerFactory,
+          status, drop, authorityOverride);
+    }
+
+    /**
+     * Creates a new {@code PickResult} with the given {@code streamTracerFactory},
+     * but retains all other properties from this {@code PickResult}.
+     *
+     * @since 1.80.0
+     */
+    public PickResult copyWithStreamTracerFactory(
+        @Nullable ClientStreamTracer.Factory streamTracerFactory) {
+      return new PickResult(subchannel, streamTracerFactory, status, drop, authorityOverride);
+    }
+
     /**
      * A decision to report a connectivity error to the RPC.  If the RPC is {@link
      * CallOptions#withWaitForReady wait-for-ready}, it will stay buffered.  Otherwise, it will fail

api/src/main/java/io/grpc/LoadBalancerRegistry.java

@@ -26,6 +26,7 @@
 import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
+import java.util.ServiceLoader;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 import javax.annotation.Nullable;
@@ -42,7 +43,6 @@
 public final class LoadBalancerRegistry {
   private static final Logger logger = Logger.getLogger(LoadBalancerRegistry.class.getName());
   private static LoadBalancerRegistry instance;
-  private static final Iterable<Class<?>> HARDCODED_CLASSES = getHardCodedClasses();
 
   private final LinkedHashSet<LoadBalancerProvider> allProviders =
       new LinkedHashSet<>();
@@ -101,8 +101,10 @@ public static synchronized LoadBalancerRegistry getDefaultRegistry() {
     if (instance == null) {
       List<LoadBalancerProvider> providerList = ServiceProviders.loadAll(
           LoadBalancerProvider.class,
-          HARDCODED_CLASSES,
-          LoadBalancerProvider.class.getClassLoader(),
+          ServiceLoader
+            .load(LoadBalancerProvider.class, LoadBalancerProvider.class.getClassLoader())
+            .iterator(),
+          LoadBalancerRegistry::getHardCodedClasses,
           new LoadBalancerPriorityAccessor());
       instance = new LoadBalancerRegistry();
       for (LoadBalancerProvider provider : providerList) {

api/src/main/java/io/grpc/ManagedChannelRegistry.java

@@ -29,6 +29,7 @@
 import java.util.Comparator;
 import java.util.LinkedHashSet;
 import java.util.List;
+import java.util.ServiceLoader;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 import javax.annotation.concurrent.ThreadSafe;
@@ -100,8 +101,10 @@ public static synchronized ManagedChannelRegistry getDefaultRegistry() {
     if (instance == null) {
       List<ManagedChannelProvider> providerList = ServiceProviders.loadAll(
           ManagedChannelProvider.class,
-          getHardCodedClasses(),
-          ManagedChannelProvider.class.getClassLoader(),
+          ServiceLoader
+            .load(ManagedChannelProvider.class, ManagedChannelProvider.class.getClassLoader())
+            .iterator(),
+          ManagedChannelRegistry::getHardCodedClasses,
           new ManagedChannelPriorityAccessor());
       instance = new ManagedChannelRegistry();
       for (ManagedChannelProvider provider : providerList) {

api/src/main/java/io/grpc/NameResolverRegistry.java

@@ -29,6 +29,7 @@
 import java.util.List;
 import java.util.Locale;
 import java.util.Map;
+import java.util.ServiceLoader;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 import javax.annotation.Nullable;
@@ -125,8 +126,10 @@ public static synchronized NameResolverRegistry getDefaultRegistry() {
     if (instance == null) {
       List<NameResolverProvider> providerList = ServiceProviders.loadAll(
           NameResolverProvider.class,
-          getHardCodedClasses(),
-          NameResolverProvider.class.getClassLoader(),
+          ServiceLoader
+            .load(NameResolverProvider.class, NameResolverProvider.class.getClassLoader())
+            .iterator(),
+          NameResolverRegistry::getHardCodedClasses,
           new NameResolverPriorityAccessor());
       if (providerList.isEmpty()) {
         logger.warning("No NameResolverProviders found via ServiceLoader, including for DNS. This "

api/src/main/java/io/grpc/ServerRegistry.java

@@ -24,6 +24,7 @@
 import java.util.Comparator;
 import java.util.LinkedHashSet;
 import java.util.List;
+import java.util.ServiceLoader;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 import javax.annotation.concurrent.ThreadSafe;
@@ -93,8 +94,9 @@ public static synchronized ServerRegistry getDefaultRegistry() {
     if (instance == null) {
       List<ServerProvider> providerList = ServiceProviders.loadAll(
           ServerProvider.class,
-          getHardCodedClasses(),
-          ServerProvider.class.getClassLoader(),
+          ServiceLoader.load(ServerProvider.class, ServerProvider.class.getClassLoader())
+            .iterator(),
+          ServerRegistry::getHardCodedClasses,
           new ServerPriorityAccessor());
       instance = new ServerRegistry();
       for (ServerProvider provider : providerList) {

api/src/main/java/io/grpc/ServiceProviders.java

@@ -17,10 +17,13 @@
 package io.grpc;
 
 import com.google.common.annotations.VisibleForTesting;
+import com.google.common.base.Supplier;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Comparator;
+import java.util.Iterator;
 import java.util.List;
+import java.util.ListIterator;
 import java.util.ServiceConfigurationError;
 import java.util.ServiceLoader;
 
@@ -34,20 +37,39 @@ private ServiceProviders() {
    * {@link ServiceLoader}.
    * If this is Android, returns all available implementations in {@code hardcoded}.
    * The list is sorted in descending priority order.
+   *
+   * <p>{@code serviceLoader} should be created with {@code ServiceLoader.load(MyClass.class,
+   * MyClass.class.getClassLoader()).iterator()} in order to be detected by R8 so that R8 full mode
+   * will keep the constructors for the provider classes.
    */
   public static <T> List<T> loadAll(
       Class<T> klass,
-      Iterable<Class<?>> hardcoded,
-      ClassLoader cl,
+      Iterator<T> serviceLoader,
+      Supplier<Iterable<Class<?>>> hardcoded,
       final PriorityAccessor<T> priorityAccessor) {
-    Iterable<T> candidates;
-    if (isAndroid(cl)) {
-      candidates = getCandidatesViaHardCoded(klass, hardcoded);
+    Iterator<T> candidates;
+    if (serviceLoader instanceof ListIterator) {
+      // A rewriting tool has replaced the ServiceLoader with a List of some sort (R8 uses
+      // ArrayList, AppReduce uses singletonList). We prefer to use such iterators on Android as
+      // they won't need reflection like the hard-coded list does. In addition, the provider
+      // instances will have already been created, so it seems we should use them.
+      //
+      // R8: https://r8.googlesource.com/r8/+/490bc53d9310d4cc2a5084c05df4aadaec8c885d/src/main/java/com/android/tools/r8/ir/optimize/ServiceLoaderRewriter.java
+      // AppReduce: service_loader_pass.cc
+      candidates = serviceLoader;
+    } else if (isAndroid(klass.getClassLoader())) {
+      // Avoid getResource() on Android, which must read from a zip which uses a lot of memory
+      candidates = getCandidatesViaHardCoded(klass, hardcoded.get()).iterator();
+    } else if (!serviceLoader.hasNext()) {
+      // Attempt to load using the context class loader and ServiceLoader.
+      // This allows frameworks like http://aries.apache.org/modules/spi-fly.html to plug in.
+      candidates = ServiceLoader.load(klass).iterator();
     } else {
-      candidates = getCandidatesViaServiceLoader(klass, cl);
+      candidates = serviceLoader;
     }
     List<T> list = new ArrayList<>();
-    for (T current: candidates) {
+    while (candidates.hasNext()) {
+      T current = candidates.next();
       if (!priorityAccessor.isAvailable(current)) {
         continue;
       }
@@ -84,15 +106,14 @@ static boolean isAndroid(ClassLoader cl) {
   }
 
   /**
-   * Loads service providers for the {@code klass} service using {@link ServiceLoader}.
+   * For testing only: Loads service providers for the {@code klass} service using {@link
+   * ServiceLoader}. Does not support spi-fly and related tricks.
    */
   @VisibleForTesting
   public static <T> Iterable<T> getCandidatesViaServiceLoader(Class<T> klass, ClassLoader cl) {
     Iterable<T> i = ServiceLoader.load(klass, cl);
-    // Attempt to load using the context class loader and ServiceLoader.
-    // This allows frameworks like http://aries.apache.org/modules/spi-fly.html to plug in.
     if (!i.iterator().hasNext()) {
-      i = ServiceLoader.load(klass);
+      return null;
     }
     return i;
   }