Remove and ban ImmutableSet#copyOf

It was used heavily in the Guice we've embedded.

core/src/main/java/org/elasticsearch/cluster/block/ClusterBlocks.java

@@ -20,7 +20,6 @@
 package org.elasticsearch.cluster.block;
 
 import com.google.common.collect.ImmutableMap;
-import com.google.common.collect.ImmutableSet;
 
 import org.elasticsearch.cluster.AbstractDiffable;
 import org.elasticsearch.cluster.metadata.IndexMetaData;
@@ -152,7 +151,7 @@ public class ClusterBlocks extends AbstractDiffable<ClusterBlocks> {
         if (global(level).isEmpty()) {
             return null;
         }
-        return new ClusterBlockException(ImmutableSet.copyOf(global(level)));
+        return new ClusterBlockException(global(level));
     }
 
     public void indexBlockedRaiseException(ClusterBlockLevel level, String index) throws ClusterBlockException {

core/src/main/java/org/elasticsearch/cluster/routing/allocation/RoutingAllocation.java

@@ -19,7 +19,6 @@
 
 package org.elasticsearch.cluster.routing.allocation;
 
-import com.google.common.collect.ImmutableSet;
 import org.elasticsearch.cluster.ClusterInfo;
 import org.elasticsearch.cluster.metadata.MetaData;
 import org.elasticsearch.cluster.node.DiscoveryNodes;
@@ -34,6 +33,9 @@ import java.util.HashSet;
 import java.util.Map;
 import java.util.Set;
 
+import static java.util.Collections.emptySet;
+import static java.util.Collections.unmodifiableSet;
+
 /**
  * The {@link RoutingAllocation} keep the state of the current allocation
  * of shards and holds the {@link AllocationDeciders} which are responsible
@@ -220,13 +222,13 @@ public class RoutingAllocation {
 
     public Set<String> getIgnoreNodes(ShardId shardId) {
         if (ignoredShardToNodes == null) {
-            return ImmutableSet.of();
+            return emptySet();
         }
         Set<String> ignore = ignoredShardToNodes.get(shardId);
         if (ignore == null) {
-            return ImmutableSet.of();
+            return emptySet();
         }
-        return ImmutableSet.copyOf(ignore);
+        return unmodifiableSet(new HashSet<>(ignore));
     }
 
     /**

core/src/main/java/org/elasticsearch/common/inject/ConfigurationException.java

@@ -16,12 +16,15 @@
 
 package org.elasticsearch.common.inject;
 
-import com.google.common.collect.ImmutableSet;
 import org.elasticsearch.common.inject.internal.Errors;
 import org.elasticsearch.common.inject.spi.Message;
 
 import java.util.Collection;
 import java.util.Locale;
+import java.util.Set;
+
+import static java.util.Collections.unmodifiableSet;
+import static org.elasticsearch.common.util.set.Sets.newHashSet;
 
 /**
  * Thrown when a programming error such as a misplaced annotation, illegal binding, or unsupported
@@ -31,15 +34,14 @@ import java.util.Locale;
  * @since 2.0
  */
 public final class ConfigurationException extends RuntimeException {
-
+    private final Set<Message> messages;
-    private final ImmutableSet<Message> messages;
     private Object partialValue = null;
 
     /**
      * Creates a ConfigurationException containing {@code messages}.
      */
     public ConfigurationException(Iterable<Message> messages) {
-        this.messages = ImmutableSet.copyOf(messages);
+        this.messages = unmodifiableSet(newHashSet(messages));
         initCause(Errors.getOnlyCause(this.messages));
     }
 

core/src/main/java/org/elasticsearch/common/inject/CreationException.java

@@ -16,7 +16,6 @@
 
 package org.elasticsearch.common.inject;
 
-import com.google.common.collect.ImmutableSet;
 import org.elasticsearch.common.inject.internal.Errors;
 import org.elasticsearch.common.inject.spi.Message;
 
@@ -29,14 +28,13 @@ import java.util.Collection;
  * @author crazybob@google.com (Bob Lee)
  */
 public class CreationException extends RuntimeException {
-
+    private final Collection<Message> messages;
-    private final ImmutableSet<Message> messages;
 
     /**
      * Creates a CreationException containing {@code messages}.
      */
     public CreationException(Collection<Message> messages) {
-        this.messages = ImmutableSet.copyOf(messages);
+        this.messages = messages;
         if (this.messages.isEmpty()) {
             throw new IllegalArgumentException();
         }

core/src/main/java/org/elasticsearch/common/inject/InjectorBuilder.java

@@ -16,15 +16,15 @@
 
 package org.elasticsearch.common.inject;
 
-import com.google.common.collect.ImmutableSet;
+import org.elasticsearch.common.inject.internal.BindingImpl;
-import org.elasticsearch.common.inject.internal.*;
+import org.elasticsearch.common.inject.internal.Errors;
+import org.elasticsearch.common.inject.internal.ErrorsException;
+import org.elasticsearch.common.inject.internal.InternalContext;
+import org.elasticsearch.common.inject.internal.Stopwatch;
 import org.elasticsearch.common.inject.spi.Dependency;
-import org.elasticsearch.common.util.iterable.Iterables;
 
-import java.util.Collection;
 import java.util.List;
 import java.util.Map;
-import java.util.Set;
 
 /**
  * Builds a tree of injectors. This is a primary injector, plus child injectors needed for each
@@ -182,12 +182,16 @@ class InjectorBuilder {
      * Loads eager singletons, or all singletons if we're in Stage.PRODUCTION. Bindings discovered
      * while we're binding these singletons are not be eager.
      */
-    public void loadEagerSingletons(InjectorImpl injector, Stage stage, final Errors errors) {
+    public void loadEagerSingletons(InjectorImpl injector, Stage stage, Errors errors) {
-        @SuppressWarnings("unchecked") // casting Collection<Binding> to Collection<BindingImpl> is safe
+        for (final Binding<?> binding : injector.state.getExplicitBindingsThisLevel().values()) {
-                Set<BindingImpl<?>> candidateBindings = ImmutableSet.copyOf(Iterables.concat(
+            loadEagerSingletons(injector, stage, errors, (BindingImpl<?>)binding);
-                (Collection) injector.state.getExplicitBindingsThisLevel().values(),
+        }
-                injector.jitBindings.values()));
+        for (final Binding<?> binding : injector.jitBindings.values()) {
-        for (final BindingImpl<?> binding : candidateBindings) {
+            loadEagerSingletons(injector, stage, errors, (BindingImpl<?>)binding);
+        }
+    }
+
+    private void loadEagerSingletons(InjectorImpl injector, Stage stage, final Errors errors, BindingImpl<?> binding) {
         if (binding.getScoping().isEagerSingleton(stage)) {
             try {
                 injector.callInContext(new ContextualCallable<Void>() {
@@ -213,7 +217,6 @@ class InjectorBuilder {
             }
         }
     }
-    }
 
     /**
      * {@link Injector} exposed to users in {@link Stage#TOOL}.

core/src/main/java/org/elasticsearch/common/inject/InjectorShell.java

@@ -25,6 +25,7 @@ import java.util.List;
 import java.util.Objects;
 import java.util.logging.Logger;
 
+import static java.util.Collections.emptySet;
 import static org.elasticsearch.common.inject.Scopes.SINGLETON;
 
 /**
@@ -185,7 +186,7 @@ class InjectorShell {
         injector.state.putBinding(key,
                 new ProviderInstanceBindingImpl<>(injector, key, SourceProvider.UNKNOWN_SOURCE,
                         injectorFactory, Scoping.UNSCOPED, injectorFactory,
-                        ImmutableSet.<InjectionPoint>of()));
+                        emptySet()));
     }
 
     private static class InjectorFactory implements InternalFactory<Injector>, Provider<Injector> {
@@ -222,7 +223,7 @@ class InjectorShell {
         injector.state.putBinding(key,
                 new ProviderInstanceBindingImpl<>(injector, key,
                         SourceProvider.UNKNOWN_SOURCE, loggerFactory, Scoping.UNSCOPED,
-                        loggerFactory, ImmutableSet.<InjectionPoint>of()));
+                        loggerFactory, emptySet()));
     }
 
     private static class LoggerFactory implements InternalFactory<Logger>, Provider<Logger> {

core/src/main/java/org/elasticsearch/common/inject/ProvisionException.java

@@ -16,12 +16,16 @@
 
 package org.elasticsearch.common.inject;
 
-import com.google.common.collect.ImmutableSet;
 import org.elasticsearch.common.inject.internal.Errors;
 import org.elasticsearch.common.inject.spi.Message;
 
 import java.util.Collection;
 import java.util.Collections;
+import java.util.Set;
+
+import static java.util.Collections.singleton;
+import static java.util.Collections.unmodifiableSet;
+import static org.elasticsearch.common.util.set.Sets.newHashSet;
 
 /**
  * Indicates that there was a runtime failure while providing an instance.
@@ -31,14 +35,13 @@ import java.util.Collections;
  * @since 2.0
  */
 public final class ProvisionException extends RuntimeException {
-
+    private final Set<Message> messages;
-    private final ImmutableSet<Message> messages;
 
     /**
      * Creates a ConfigurationException containing {@code messages}.
      */
     public ProvisionException(Iterable<Message> messages) {
-        this.messages = ImmutableSet.copyOf(messages);
+        this.messages = unmodifiableSet(newHashSet(messages));
         if (this.messages.isEmpty()) {
             throw new IllegalArgumentException();
         }
@@ -47,11 +50,11 @@ public final class ProvisionException extends RuntimeException {
 
     public ProvisionException(String message, Throwable cause) {
         super(cause);
-        this.messages = ImmutableSet.of(new Message(Collections.emptyList(), message, cause));
+        this.messages = singleton(new Message(Collections.emptyList(), message, cause));
     }
 
     public ProvisionException(String message) {
-        this.messages = ImmutableSet.of(new Message(message));
+        this.messages = singleton(new Message(message));
     }
 
     /**

core/src/main/java/org/elasticsearch/common/inject/assistedinject/FactoryProvider.java

@@ -18,6 +18,7 @@ package org.elasticsearch.common.inject.assistedinject;
 
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableSet;
+
 import org.elasticsearch.common.inject.ConfigurationException;
 import org.elasticsearch.common.inject.Inject;
 import org.elasticsearch.common.inject.Injector;
@@ -37,10 +38,13 @@ import java.lang.reflect.Proxy;
 import java.lang.reflect.Type;
 import java.util.ArrayList;
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
 
+import static java.util.Collections.unmodifiableSet;
+
 /**
  * Provides a factory that combines the caller's arguments with injector-supplied values to
  * construct objects.
@@ -279,7 +283,7 @@ public class FactoryProvider<F> implements Provider<F>, HasDependencies {
 
     @Override
     public Set<Dependency<?>> getDependencies() {
-        List<Dependency<?>> dependencies = new ArrayList<>();
+        Set<Dependency<?>> dependencies = new HashSet<>();
         for (AssistedConstructor<?> constructor : factoryMethodToConstructor.values()) {
             for (Parameter parameter : constructor.getAllParameters()) {
                 if (!parameter.isProvidedByFactory()) {
@@ -287,7 +291,7 @@ public class FactoryProvider<F> implements Provider<F>, HasDependencies {
                 }
             }
         }
-        return ImmutableSet.copyOf(dependencies);
+        return unmodifiableSet(dependencies);
     }
 
     @Override

core/src/main/java/org/elasticsearch/common/inject/internal/BindingBuilder.java

@@ -16,18 +16,25 @@
 
 package org.elasticsearch.common.inject.internal;
 
-import com.google.common.collect.ImmutableSet;
+import org.elasticsearch.common.inject.Binder;
-import org.elasticsearch.common.inject.*;
+import org.elasticsearch.common.inject.ConfigurationException;
+import org.elasticsearch.common.inject.Key;
+import org.elasticsearch.common.inject.Provider;
+import org.elasticsearch.common.inject.TypeLiteral;
 import org.elasticsearch.common.inject.binder.AnnotatedBindingBuilder;
 import org.elasticsearch.common.inject.spi.Element;
 import org.elasticsearch.common.inject.spi.InjectionPoint;
 import org.elasticsearch.common.inject.spi.Message;
 
 import java.lang.annotation.Annotation;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Objects;
 import java.util.Set;
 
+import static java.util.Collections.emptySet;
+import static java.util.Collections.unmodifiableSet;
+
 /**
  * Bind a non-constant key.
  *
@@ -85,11 +92,11 @@ public class BindingBuilder<T> extends AbstractBindingBuilder<T>
                 for (Message message : e.getErrorMessages()) {
                     binder.addError(message);
                 }
-                injectionPoints = e.getPartialValue();
+                injectionPoints = unmodifiableSet(new HashSet<>(e.getPartialValue()));
             }
         } else {
             binder.addError(BINDING_TO_NULL);
-            injectionPoints = ImmutableSet.of();
+            injectionPoints = emptySet();
         }
 
         BindingImpl<T> base = getBinding();
@@ -110,7 +117,7 @@ public class BindingBuilder<T> extends AbstractBindingBuilder<T>
             for (Message message : e.getErrorMessages()) {
                 binder.addError(message);
             }
-            injectionPoints = e.getPartialValue();
+            injectionPoints = unmodifiableSet(new HashSet<>(e.getPartialValue()));
         }
 
         BindingImpl<T> base = getBinding();

core/src/main/java/org/elasticsearch/common/inject/internal/ConstantBindingBuilderImpl.java

@@ -16,17 +16,17 @@
 
 package org.elasticsearch.common.inject.internal;
 
-import com.google.common.collect.ImmutableSet;
 import org.elasticsearch.common.inject.Binder;
 import org.elasticsearch.common.inject.Key;
 import org.elasticsearch.common.inject.binder.AnnotatedConstantBindingBuilder;
 import org.elasticsearch.common.inject.binder.ConstantBindingBuilder;
 import org.elasticsearch.common.inject.spi.Element;
-import org.elasticsearch.common.inject.spi.InjectionPoint;
 
 import java.lang.annotation.Annotation;
 import java.util.List;
 
+import static java.util.Collections.emptySet;
+
 /**
  * Bind a constant.
  *
@@ -130,7 +130,7 @@ public final class ConstantBindingBuilderImpl<T>
         }
 
         setBinding(new InstanceBindingImpl<>(
-                base.getSource(), key, base.getScoping(), ImmutableSet.<InjectionPoint>of(), instanceAsT));
+                base.getSource(), key, base.getScoping(), emptySet(), instanceAsT));
     }
 
     @Override

core/src/main/java/org/elasticsearch/common/inject/internal/Errors.java

@@ -17,6 +17,7 @@
 package org.elasticsearch.common.inject.internal;
 
 import com.google.common.collect.ImmutableSet;
+
 import org.apache.lucene.util.CollectionUtil;
 import org.elasticsearch.common.inject.ConfigurationException;
 import org.elasticsearch.common.inject.CreationException;
@@ -49,6 +50,8 @@ import java.util.Formatter;
 import java.util.List;
 import java.util.Locale;
 
+import static java.util.Collections.unmodifiableList;
+
 /**
  * A collection of error messages. If this type is passed as a method parameter, the method is
  * considered to have executed successfully only if new errors were not added to this collection.
@@ -463,7 +466,7 @@ public final class Errors implements Serializable {
             }
         });
 
-        return result;
+        return unmodifiableList(result);
     }
 
     /**

core/src/main/java/org/elasticsearch/common/inject/internal/InstanceBindingImpl.java

@@ -16,27 +16,33 @@
 
 package org.elasticsearch.common.inject.internal;
 
-import com.google.common.collect.ImmutableSet;
 import org.elasticsearch.common.inject.Binder;
 import org.elasticsearch.common.inject.Injector;
 import org.elasticsearch.common.inject.Key;
 import org.elasticsearch.common.inject.Provider;
-import org.elasticsearch.common.inject.spi.*;
+import org.elasticsearch.common.inject.spi.BindingTargetVisitor;
+import org.elasticsearch.common.inject.spi.Dependency;
+import org.elasticsearch.common.inject.spi.HasDependencies;
+import org.elasticsearch.common.inject.spi.InjectionPoint;
+import org.elasticsearch.common.inject.spi.InstanceBinding;
 import org.elasticsearch.common.inject.util.Providers;
 
+import java.util.HashSet;
 import java.util.Set;
 
+import static java.util.Collections.unmodifiableSet;
+
 public class InstanceBindingImpl<T> extends BindingImpl<T> implements InstanceBinding<T> {
 
     final T instance;
     final Provider<T> provider;
-    final ImmutableSet<InjectionPoint> injectionPoints;
+    final Set<InjectionPoint> injectionPoints;
 
     public InstanceBindingImpl(Injector injector, Key<T> key, Object source,
                                InternalFactory<? extends T> internalFactory, Set<InjectionPoint> injectionPoints,
                                T instance) {
         super(injector, key, source, internalFactory, Scoping.UNSCOPED);
-        this.injectionPoints = ImmutableSet.copyOf(injectionPoints);
+        this.injectionPoints = injectionPoints;
         this.instance = instance;
         this.provider = Providers.of(instance);
     }
@@ -44,7 +50,7 @@ public class InstanceBindingImpl<T> extends BindingImpl<T> implements InstanceBi
     public InstanceBindingImpl(Object source, Key<T> key, Scoping scoping,
                                Set<InjectionPoint> injectionPoints, T instance) {
         super(source, key, scoping);
-        this.injectionPoints = ImmutableSet.copyOf(injectionPoints);
+        this.injectionPoints = injectionPoints;
         this.instance = instance;
         this.provider = Providers.of(instance);
     }
@@ -72,7 +78,7 @@ public class InstanceBindingImpl<T> extends BindingImpl<T> implements InstanceBi
     @Override
     public Set<Dependency<?>> getDependencies() {
         return instance instanceof HasDependencies
-                ? ImmutableSet.copyOf(((HasDependencies) instance).getDependencies())
+                ? unmodifiableSet(new HashSet<>((((HasDependencies) instance).getDependencies())))
                 : Dependency.forInjectionPoints(injectionPoints);
     }
 

core/src/main/java/org/elasticsearch/common/inject/internal/ProviderInstanceBindingImpl.java

@@ -16,20 +16,26 @@ limitations under the License.
 
 package org.elasticsearch.common.inject.internal;
 
-import com.google.common.collect.ImmutableSet;
 import org.elasticsearch.common.inject.Binder;
 import org.elasticsearch.common.inject.Injector;
 import org.elasticsearch.common.inject.Key;
 import org.elasticsearch.common.inject.Provider;
-import org.elasticsearch.common.inject.spi.*;
+import org.elasticsearch.common.inject.spi.BindingTargetVisitor;
+import org.elasticsearch.common.inject.spi.Dependency;
+import org.elasticsearch.common.inject.spi.HasDependencies;
+import org.elasticsearch.common.inject.spi.InjectionPoint;
+import org.elasticsearch.common.inject.spi.ProviderInstanceBinding;
 
+import java.util.HashSet;
 import java.util.Set;
 
+import static java.util.Collections.unmodifiableSet;
+
 public final class ProviderInstanceBindingImpl<T> extends BindingImpl<T>
         implements ProviderInstanceBinding<T> {
 
     final Provider<? extends T> providerInstance;
-    final ImmutableSet<InjectionPoint> injectionPoints;
+    final Set<InjectionPoint> injectionPoints;
 
     public ProviderInstanceBindingImpl(Injector injector, Key<T> key,
                                        Object source, InternalFactory<? extends T> internalFactory, Scoping scoping,
@@ -37,13 +43,13 @@ public final class ProviderInstanceBindingImpl<T> extends BindingImpl<T>
                                        Set<InjectionPoint> injectionPoints) {
         super(injector, key, source, internalFactory, scoping);
         this.providerInstance = providerInstance;
-        this.injectionPoints = ImmutableSet.copyOf(injectionPoints);
+        this.injectionPoints = injectionPoints;
     }
 
     public ProviderInstanceBindingImpl(Object source, Key<T> key, Scoping scoping,
                                        Set<InjectionPoint> injectionPoints, Provider<? extends T> providerInstance) {
         super(source, key, scoping);
-        this.injectionPoints = ImmutableSet.copyOf(injectionPoints);
+        this.injectionPoints = injectionPoints;
         this.providerInstance = providerInstance;
     }
 
@@ -65,7 +71,7 @@ public final class ProviderInstanceBindingImpl<T> extends BindingImpl<T>
     @Override
     public Set<Dependency<?>> getDependencies() {
         return providerInstance instanceof HasDependencies
-                ? ImmutableSet.copyOf(((HasDependencies) providerInstance).getDependencies())
+                ? unmodifiableSet(new HashSet<>((((HasDependencies) providerInstance).getDependencies())))
                 : Dependency.forInjectionPoints(injectionPoints);
     }
 

core/src/main/java/org/elasticsearch/common/inject/internal/ProviderMethod.java

@@ -16,8 +16,11 @@
 
 package org.elasticsearch.common.inject.internal;
 
-import com.google.common.collect.ImmutableSet;
+import org.elasticsearch.common.inject.Binder;
-import org.elasticsearch.common.inject.*;
+import org.elasticsearch.common.inject.Exposed;
+import org.elasticsearch.common.inject.Key;
+import org.elasticsearch.common.inject.PrivateBinder;
+import org.elasticsearch.common.inject.Provider;
 import org.elasticsearch.common.inject.spi.Dependency;
 import org.elasticsearch.common.inject.spi.ProviderWithDependencies;
 
@@ -37,7 +40,7 @@ public class ProviderMethod<T> implements ProviderWithDependencies<T> {
     private final Class<? extends Annotation> scopeAnnotation;
     private final Object instance;
     private final Method method;
-    private final ImmutableSet<Dependency<?>> dependencies;
+    private final Set<Dependency<?>> dependencies;
     private final List<Provider<?>> parameterProviders;
     private final boolean exposed;
 
@@ -45,7 +48,7 @@ public class ProviderMethod<T> implements ProviderWithDependencies<T> {
      * @param method the method to invoke. Its return type must be the same type as {@code key}.
      */
     ProviderMethod(Key<T> key, Method method, Object instance,
-                   ImmutableSet<Dependency<?>> dependencies, List<Provider<?>> parameterProviders,
+                   Set<Dependency<?>> dependencies, List<Provider<?>> parameterProviders,
                    Class<? extends Annotation> scopeAnnotation) {
         this.key = key;
         this.scopeAnnotation = scopeAnnotation;

core/src/main/java/org/elasticsearch/common/inject/internal/ProviderMethodsModule.java

@@ -16,7 +16,6 @@
 
 package org.elasticsearch.common.inject.internal;
 
-import com.google.common.collect.ImmutableSet;
 import org.elasticsearch.common.inject.Binder;
 import org.elasticsearch.common.inject.Key;
 import org.elasticsearch.common.inject.Module;
@@ -31,8 +30,12 @@ import java.lang.annotation.Annotation;
 import java.lang.reflect.Member;
 import java.lang.reflect.Method;
 import java.util.ArrayList;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Objects;
+import java.util.Set;
+
+import static java.util.Collections.unmodifiableSet;
 
 /**
  * Creates bindings to methods annotated with {@literal @}{@link Provides}. Use the scope and
@@ -94,7 +97,7 @@ public final class ProviderMethodsModule implements Module {
         Errors errors = new Errors(method);
 
         // prepare the parameter providers
-        List<Dependency<?>> dependencies = new ArrayList<>();
+        Set<Dependency<?>> dependencies = new HashSet<>();
         List<Provider<?>> parameterProviders = new ArrayList<>();
         List<TypeLiteral<?>> parameterTypes = typeLiteral.getParameterTypes(method);
         Annotation[][] parameterAnnotations = method.getParameterAnnotations();
@@ -115,7 +118,7 @@ public final class ProviderMethodsModule implements Module {
             binder.addError(message);
         }
 
-        return new ProviderMethod<>(key, method, delegate, ImmutableSet.copyOf(dependencies),
+        return new ProviderMethod<>(key, method, delegate, unmodifiableSet(dependencies),
                 parameterProviders, scopeAnnotation);
     }
 

core/src/main/java/org/elasticsearch/common/inject/internal/SourceProvider.java

@@ -16,11 +16,11 @@
 
 package org.elasticsearch.common.inject.internal;
 
-import com.google.common.collect.ImmutableSet;
+import java.util.HashSet;
-import org.elasticsearch.common.util.iterable.Iterables;
+import java.util.Set;
 
-import java.util.ArrayList;
+import static java.util.Collections.singleton;
-import java.util.List;
+import static java.util.Collections.unmodifiableSet;
 
 /**
  * Provides access to the calling line of code.
@@ -34,35 +34,29 @@ public class SourceProvider {
      */
     public static final Object UNKNOWN_SOURCE = "[unknown source]";
 
-    private final ImmutableSet<String> classNamesToSkip;
+    private final Set<String> classNamesToSkip;
 
     public SourceProvider() {
-        this.classNamesToSkip = ImmutableSet.of(SourceProvider.class.getName());
+        this.classNamesToSkip = singleton(SourceProvider.class.getName());
     }
 
-    public static final SourceProvider DEFAULT_INSTANCE
+    public static final SourceProvider DEFAULT_INSTANCE = new SourceProvider();
-            = new SourceProvider(ImmutableSet.of(SourceProvider.class.getName()));
 
-    private SourceProvider(Iterable<String> classesToSkip) {
+    @SuppressWarnings("rawtypes")
-        this.classNamesToSkip = ImmutableSet.copyOf(classesToSkip);
+    private SourceProvider(SourceProvider copy, Class[] moreClassesToSkip) {
+        Set<String> classNamesToSkip = new HashSet<>(copy.classNamesToSkip);
+        for (Class toSkip : moreClassesToSkip) {
+            classNamesToSkip.add(toSkip.getName());
+        }
+        this.classNamesToSkip = unmodifiableSet(classNamesToSkip);
     }
 
     /**
      * Returns a new instance that also skips {@code moreClassesToSkip}.
      */
+    @SuppressWarnings("rawtypes")
     public SourceProvider plusSkippedClasses(Class... moreClassesToSkip) {
-        return new SourceProvider(Iterables.concat(classNamesToSkip, asStrings(moreClassesToSkip)));
+        return new SourceProvider(this, moreClassesToSkip);
-    }
-
-    /**
-     * Returns the class names as Strings
-     */
-    private static List<String> asStrings(Class... classes) {
-        List<String> strings = new ArrayList<>();
-        for (Class c : classes) {
-            strings.add(c.getName());
-        }
-        return strings;
     }
 
     /**

core/src/main/java/org/elasticsearch/common/inject/multibindings/Multibinder.java

@@ -17,6 +17,7 @@
 package org.elasticsearch.common.inject.multibindings;
 
 import com.google.common.collect.ImmutableSet;
+
 import org.elasticsearch.common.inject.Binder;
 import org.elasticsearch.common.inject.Binding;
 import org.elasticsearch.common.inject.ConfigurationException;
@@ -37,11 +38,14 @@ import java.lang.annotation.Annotation;
 import java.lang.reflect.Type;
 import java.util.ArrayList;
 import java.util.Collections;
+import java.util.HashSet;
 import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Objects;
 import java.util.Set;
 
+import static java.util.Collections.unmodifiableSet;
+
 /**
  * An API to bind multiple values separately, only to later inject them as a
  * complete collection. Multibinder is intended for use in your application's
@@ -238,9 +242,8 @@ public abstract class Multibinder<T> {
         @Inject
         public void initialize(Injector injector) {
             providers = new ArrayList<>();
-            List<Dependency<?>> dependencies = new ArrayList<>();
+            Set<Dependency<?>> dependencies = new HashSet<>();
             for (Binding<?> entry : injector.findBindingsByType(elementType)) {
-
                 if (keyMatches(entry.getKey())) {
                     @SuppressWarnings("unchecked") // protected by findBindingsByType()
                             Binding<T> binding = (Binding<T>) entry;
@@ -249,7 +252,7 @@ public abstract class Multibinder<T> {
                 }
             }
 
-            this.dependencies = ImmutableSet.copyOf(dependencies);
+            this.dependencies = unmodifiableSet(dependencies);
             this.binder = null;
         }
 

core/src/main/java/org/elasticsearch/common/inject/spi/Dependency.java

@@ -16,14 +16,14 @@
 
 package org.elasticsearch.common.inject.spi;
 
-import com.google.common.collect.ImmutableSet;
 import org.elasticsearch.common.inject.Key;
 
-import java.util.ArrayList;
-import java.util.List;
 import java.util.Objects;
 import java.util.Set;
 
+import static java.util.Collections.unmodifiableSet;
+import static org.elasticsearch.common.util.set.Sets.toFlatSet;
+
 /**
  * A variable that can be resolved by an injector.
  * <p>
@@ -60,11 +60,8 @@ public final class Dependency<T> {
      * Returns the dependencies from the given injection points.
      */
     public static Set<Dependency<?>> forInjectionPoints(Set<InjectionPoint> injectionPoints) {
-        List<Dependency<?>> dependencies = new ArrayList<>();
+        return unmodifiableSet(
-        for (InjectionPoint injectionPoint : injectionPoints) {
+                injectionPoints.stream().map(InjectionPoint::getDependencies).collect(toFlatSet()));
-            dependencies.addAll(injectionPoint.getDependencies());
-        }
-        return ImmutableSet.copyOf(dependencies);
     }
 
     /**

core/src/main/java/org/elasticsearch/common/inject/spi/InjectionPoint.java

@@ -17,6 +17,7 @@
 package org.elasticsearch.common.inject.spi;
 
 import com.google.common.collect.ImmutableSet;
+
 import org.elasticsearch.common.inject.ConfigurationException;
 import org.elasticsearch.common.inject.Inject;
 import org.elasticsearch.common.inject.Key;
@@ -38,10 +39,12 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
+import java.util.HashSet;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Set;
 
+import static java.util.Collections.unmodifiableSet;
 import static org.elasticsearch.common.inject.internal.MoreTypes.getRawType;
 
 /**
@@ -253,13 +256,13 @@ public final class InjectionPoint {
      *                                of the valid injection points.
      */
     public static Set<InjectionPoint> forStaticMethodsAndFields(TypeLiteral type) {
-        List<InjectionPoint> sink = new ArrayList<>();
+        Set<InjectionPoint> result = new HashSet<>();
         Errors errors = new Errors();
 
-        addInjectionPoints(type, Factory.FIELDS, true, sink, errors);
+        addInjectionPoints(type, Factory.FIELDS, true, result, errors);
-        addInjectionPoints(type, Factory.METHODS, true, sink, errors);
+        addInjectionPoints(type, Factory.METHODS, true, result, errors);
 
-        ImmutableSet<InjectionPoint> result = ImmutableSet.copyOf(sink);
+        result = unmodifiableSet(result);
         if (errors.hasErrors()) {
             throw new ConfigurationException(errors.getMessages()).withPartialValue(result);
         }
@@ -293,14 +296,14 @@ public final class InjectionPoint {
      *                                of the valid injection points.
      */
     public static Set<InjectionPoint> forInstanceMethodsAndFields(TypeLiteral<?> type) {
-        List<InjectionPoint> sink = new ArrayList<>();
+        Set<InjectionPoint> result = new HashSet<>();
         Errors errors = new Errors();
 
         // TODO (crazybob): Filter out overridden members.
-        addInjectionPoints(type, Factory.FIELDS, false, sink, errors);
+        addInjectionPoints(type, Factory.FIELDS, false, result, errors);
-        addInjectionPoints(type, Factory.METHODS, false, sink, errors);
+        addInjectionPoints(type, Factory.METHODS, false, result, errors);
 
-        ImmutableSet<InjectionPoint> result = ImmutableSet.copyOf(sink);
+        result = unmodifiableSet(result);
         if (errors.hasErrors()) {
             throw new ConfigurationException(errors.getMessages()).withPartialValue(result);
         }

core/src/main/java/org/elasticsearch/common/inject/util/Modules.java

@@ -16,7 +16,6 @@
 
 package org.elasticsearch.common.inject.util;
 
-import com.google.common.collect.ImmutableSet;
 import org.elasticsearch.common.inject.AbstractModule;
 import org.elasticsearch.common.inject.Binder;
 import org.elasticsearch.common.inject.Binding;
@@ -40,6 +39,9 @@ import java.util.List;
 import java.util.Map;
 import java.util.Set;
 
+import static java.util.Collections.unmodifiableSet;
+import static org.elasticsearch.common.util.set.Sets.newHashSet;
+
 /**
  * Static utility methods for creating and working with instances of {@link Module}.
  *
@@ -94,15 +96,14 @@ public final class Modules {
      * Returns a new module that installs all of {@code modules}.
      */
     public static Module combine(Module... modules) {
-        return combine(ImmutableSet.copyOf(modules));
+        return combine(Arrays.asList(modules));
     }
 
     /**
      * Returns a new module that installs all of {@code modules}.
      */
     public static Module combine(Iterable<? extends Module> modules) {
-        // TODO: infer type once JI-9019884 is fixed
+        final Set<? extends Module> modulesSet = newHashSet(modules);
-        final Set<Module> modulesSet = ImmutableSet.<Module>copyOf(modules);
         return new Module() {
             @Override
             public void configure(Binder binder) {
@@ -131,11 +132,10 @@ public final class Modules {
     }
 
     private static final class RealOverriddenModuleBuilder implements OverriddenModuleBuilder {
-        private final ImmutableSet<Module> baseModules;
+        private final Set<Module> baseModules;
 
         private RealOverriddenModuleBuilder(Iterable<? extends Module> baseModules) {
-            // TODO: infer type once JI-9019884 is fixed
+            this.baseModules = unmodifiableSet(newHashSet(baseModules));
-            this.baseModules = ImmutableSet.<Module>copyOf(baseModules);
         }
 
         @Override

core/src/main/java/org/elasticsearch/common/util/set/Sets.java

@@ -21,11 +21,17 @@ package org.elasticsearch.common.util.set;
 
 import java.util.Collection;
 import java.util.Collections;
+import java.util.EnumSet;
 import java.util.HashSet;
 import java.util.Iterator;
 import java.util.Objects;
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.function.BiConsumer;
+import java.util.function.BinaryOperator;
+import java.util.function.Function;
+import java.util.function.Supplier;
+import java.util.stream.Collector;
 import java.util.stream.Collectors;
 
 public final class Sets {
@@ -66,6 +72,14 @@ public final class Sets {
         return set;
     }
 
+    /**
+     * Collects {@code Stream<Collection<T>>} into {@code Set<T>}.
+     */
+    @SuppressWarnings("unchecked")
+    public static <T> Collector<Collection<T>, Set<T>, Set<T>> toFlatSet() {
+        return (Collector<Collection<T>, Set<T>, Set<T>>) (Object) ToFlatSetCollector.INSTANCE;
+    }
+
     public static <T> Set<T> newConcurrentHashSet() {
         return Collections.newSetFromMap(new ConcurrentHashMap<>());
     }
@@ -89,4 +103,39 @@ public final class Sets {
         union.addAll(right);
         return union;
     }
+
+    /**
+     * Collects {@code Stream<Collection<T>>} into {@code Set<T>}.
+     */
+    private static enum ToFlatSetCollector implements Collector<Collection<Object>, Set<Object>, Set<Object>> {
+        INSTANCE;
+
+        @Override
+        public Supplier<Set<Object>> supplier() {
+            return HashSet::new;
+        }
+
+        @Override
+        public BiConsumer<Set<Object>, Collection<Object>> accumulator() {
+            return Collection::addAll;
+        }
+
+        @Override
+        public BinaryOperator<Set<Object>> combiner() {
+            return (lhs, rhs) -> {
+                lhs.addAll(rhs);
+                return lhs;
+            };
+        }
+
+        @Override
+        public Function<Set<Object>, Set<Object>> finisher() {
+            return Function.identity();
+        }
+
+        @Override
+        public Set<java.util.stream.Collector.Characteristics> characteristics() {
+            return EnumSet.of(Collector.Characteristics.IDENTITY_FINISH, Collector.Characteristics.UNORDERED);
+        }
+    }
 }

core/src/main/java/org/elasticsearch/gateway/AsyncShardFetch.java

@@ -20,6 +20,7 @@ package org.elasticsearch.gateway;
 
 import com.carrotsearch.hppc.cursors.ObjectObjectCursor;
 import com.google.common.collect.ImmutableSet;
+
 import org.elasticsearch.ElasticsearchTimeoutException;
 import org.elasticsearch.ExceptionsHelper;
 import org.elasticsearch.action.ActionListener;
@@ -38,7 +39,13 @@ import org.elasticsearch.common.util.concurrent.EsRejectedExecutionException;
 import org.elasticsearch.index.shard.ShardId;
 import org.elasticsearch.transport.ReceiveTimeoutTransportException;
 
-import java.util.*;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Iterator;
+import java.util.Map;
+import java.util.Set;
+
+import static java.util.Collections.unmodifiableSet;
 
 /**
  * Allows to asynchronously fetch shard related data from other nodes for allocation, without blocking
@@ -143,7 +150,7 @@ public abstract class AsyncShardFetch<T extends BaseNodeResponse> implements Rel
                     }
                 }
             }
-            Set<String> allIgnoreNodes = ImmutableSet.copyOf(nodesToIgnore);
+            Set<String> allIgnoreNodes = unmodifiableSet(new HashSet<>(nodesToIgnore));
             // clear the nodes to ignore, we had a successful run in fetching everything we can
             // we need to try them if another full run is needed
             nodesToIgnore.clear();

core/src/main/java/org/elasticsearch/index/analysis/HtmlStripCharFilterFactory.java

@@ -19,7 +19,6 @@
 
 package org.elasticsearch.index.analysis;
 
-import com.google.common.collect.ImmutableSet;
 import org.apache.lucene.analysis.charfilter.HTMLStripCharFilter;
 import org.elasticsearch.common.inject.Inject;
 import org.elasticsearch.common.inject.assistedinject.Assisted;
@@ -28,26 +27,26 @@ import org.elasticsearch.index.Index;
 import org.elasticsearch.index.settings.IndexSettings;
 
 import java.io.Reader;
+import java.util.Set;
+
+import static java.util.Collections.unmodifiableSet;
+import static org.elasticsearch.common.util.set.Sets.newHashSet;
 
-/**
- *
- */
 public class HtmlStripCharFilterFactory extends AbstractCharFilterFactory {
-
+    private final Set<String> escapedTags;
-    private final ImmutableSet<String> escapedTags;
 
     @Inject
     public HtmlStripCharFilterFactory(Index index, @IndexSettings Settings indexSettings, @Assisted String name, @Assisted Settings settings) {
         super(index, indexSettings, name);
         String[] escapedTags = settings.getAsArray("escaped_tags");
         if (escapedTags.length > 0) {
-            this.escapedTags = ImmutableSet.copyOf(escapedTags);
+            this.escapedTags = unmodifiableSet(newHashSet(escapedTags));
         } else {
             this.escapedTags = null;
         }
     }
 
-    public ImmutableSet<String> escapedTags() {
+    public Set<String> escapedTags() {
         return escapedTags;
     }
 

core/src/main/java/org/elasticsearch/indices/IndicesService.java

@@ -20,7 +20,7 @@
 package org.elasticsearch.indices;
 
 import com.google.common.collect.ImmutableMap;
-import com.google.common.collect.ImmutableSet;
+
 import org.apache.lucene.store.LockObtainFailedException;
 import org.apache.lucene.util.CollectionUtil;
 import org.apache.lucene.util.IOUtils;
@@ -87,14 +87,15 @@ import java.io.IOException;
 import java.nio.file.Files;
 import java.util.ArrayList;
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.TimeUnit;
-import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
 import static org.elasticsearch.cluster.metadata.IndexMetaData.SETTING_NUMBER_OF_REPLICAS;
@@ -162,11 +163,11 @@ public class IndicesService extends AbstractLifecycleComponent<IndicesService> i
 
     @Override
     protected void doStop() {
-        ImmutableSet<String> indices = ImmutableSet.copyOf(this.indices.keySet());
+        ExecutorService indicesStopExecutor = Executors.newFixedThreadPool(5, EsExecutors.daemonThreadFactory("indices_shutdown"));
+
+        // Copy indices because we modify it asynchronously in the body of the loop
+        Set<String> indices = new HashSet<>(this.indices.keySet());
         final CountDownLatch latch = new CountDownLatch(indices.size());
-
-        final ExecutorService indicesStopExecutor = Executors.newFixedThreadPool(5, EsExecutors.daemonThreadFactory("indices_shutdown"));
-
         for (final String index : indices) {
             indicesStopExecutor.execute(new Runnable() {
                 @Override

core/src/test/java/org/elasticsearch/cluster/ClusterInfoServiceIT.java

@@ -20,6 +20,7 @@
 package org.elasticsearch.cluster;
 
 import com.google.common.collect.ImmutableSet;
+
 import org.elasticsearch.ElasticsearchException;
 import org.elasticsearch.action.ActionListener;
 import org.elasticsearch.action.ActionModule;
@@ -59,7 +60,10 @@ import java.util.Set;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.atomic.AtomicBoolean;
 
+import static java.util.Collections.emptySet;
+import static java.util.Collections.unmodifiableSet;
 import static org.elasticsearch.common.settings.Settings.settingsBuilder;
+import static org.elasticsearch.common.util.set.Sets.newHashSet;
 import static org.elasticsearch.test.hamcrest.ElasticsearchAssertions.assertAcked;
 import static org.hamcrest.CoreMatchers.equalTo;
 import static org.hamcrest.Matchers.greaterThan;
@@ -89,8 +93,7 @@ public class ClusterInfoServiceIT extends ESIntegTestCase {
     }
 
     public static class BlockingActionFilter extends org.elasticsearch.action.support.ActionFilter.Simple {
-
+        private Set<String> blockedActions = emptySet();
-        ImmutableSet<String> blockedActions = ImmutableSet.of();
 
         @Inject
         public BlockingActionFilter(Settings settings) {
@@ -116,7 +119,7 @@ public class ClusterInfoServiceIT extends ESIntegTestCase {
         }
 
         public void blockActions(String... actions) {
-            blockedActions = ImmutableSet.copyOf(actions);
+            blockedActions = unmodifiableSet(newHashSet(actions));
         }
     }
 

dev-tools/src/main/resources/forbidden/all-signatures.txt

@@ -129,6 +129,10 @@ com.google.common.io.Files
 com.google.common.primitives.Ints
 com.google.common.collect.ImmutableMap#entrySet()
 com.google.common.collect.ImmutableSet#builder()
+com.google.common.collect.ImmutableSet#copyOf(java.lang.Iterable)
+com.google.common.collect.ImmutableSet#copyOf(java.util.Iterator)
+com.google.common.collect.ImmutableSet#copyOf(java.util.Collection)
+com.google.common.collect.ImmutableSet#copyOf(java.lang.Object[])
 
 @defaultMessage Do not violate java's access system
 java.lang.reflect.AccessibleObject#setAccessible(boolean)