New aggregate type for ChannelCredentials

Author: Zgoda91

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

@@ -0,0 +1,55 @@
+/*
+ * Copyright 2025 The gRPC Authors
+ *
+ * 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;
+
+import com.google.common.base.Preconditions;
+import com.google.common.collect.ImmutableList;
+import java.io.Closeable;
+
+/**
+ * {@code ChannelCredentials} which holds allocated resources (e.g. file watchers) upon
+ * instantiation of a given {@code ChannelCredentials} object, which must be closed once
+ * mentioned {@code ChannelCredentials} are no longer in use.
+ */
+public final class ResourceAllocatingChannelCredentials extends ChannelCredentials {
+  public static ChannelCredentials create(
+      ChannelCredentials channelCreds, ImmutableList<Closeable> resources) {
+    return new ResourceAllocatingChannelCredentials(channelCreds, resources);
+  }
+
+  private final ChannelCredentials channelCreds;
+  private final ImmutableList<Closeable> resources;
+
+  private ResourceAllocatingChannelCredentials(
+      ChannelCredentials channelCreds, ImmutableList<Closeable> resources) {
+    this.channelCreds = Preconditions.checkNotNull(channelCreds, "channelCreds");
+    this.resources = Preconditions.checkNotNull(resources, "resources");
+  }
+
+  public ChannelCredentials getChannelCredentials() {
+    return channelCreds;
+  }
+
+  public ImmutableList<Closeable> getAllocatedResources() {
+    return resources;
+  }
+
+  @Override
+  public ChannelCredentials withoutBearerTokens() {
+    return channelCreds.withoutBearerTokens();
+  }
+}

api/src/test/java/io/grpc/ResourceAllocatingChannelCredentialsTest.java

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+/*
+ * Copyright 2025 The gRPC Authors
+ *
+ * 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;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import com.google.common.collect.ImmutableList;
+import java.io.Closeable;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+/** Tests for {@link ResourceAllocatingChannelCredentials}. */
+@RunWith(JUnit4.class)
+public class ResourceAllocatingChannelCredentialsTest {
+  @Test
+  public void withoutBearerTokenDelegatesCall() {
+    ChannelCredentials channelChreds = new ChannelCredentials() {
+      @Override
+      public ChannelCredentials withoutBearerTokens() {
+        return this;
+      }
+    };
+    ImmutableList<Closeable> resources = ImmutableList.<Closeable>of();
+    ChannelCredentials creds =
+        ResourceAllocatingChannelCredentials.create(channelChreds, resources);
+    assertThat(creds.withoutBearerTokens()).isEqualTo(channelChreds);
+  }
+}