Java surface refactoring on GAX

Java surface refactoring on GAX

- Settings classes (ApiCallSettings, ServiceApiSettings) are converted
  from mutable classes to immutable classes with builders.
- The builders in ApiCallable become builders in individual top-level
  settings classes.
- ServiceApiSettings.allCallSettings removed, replaced with
  applyToAllMethods(ApiCallSettings.Builder)
- Renamed getChannel (now in ServiceApiSettings.Builder) to
  getOrBuildChannel; also getExecutor -> getOrBuildExecutor
- Rename RetryParams to RetrySettings for consistency.

src/main/java/com/google/api/gax/core/RetryParams.java → src/main/java/com/google/api/gax/core/RetrySettings.java

@@ -39,11 +39,10 @@
 
 /**
  * {@code RetryParams} encapsulates a retry strategy used by
- * {@link com.google.api.gax.grpc.ApiCallable#retrying(RetryParams, ScheduledExecutorService)}.
+ * {@link com.google.api.gax.grpc.ApiCallable#retrying(RetrySettings, ScheduledExecutorService)}.
  */
 @AutoValue
-public abstract class RetryParams {
-
+public abstract class RetrySettings {
 
   public abstract Duration getTotalTimeout();
 
@@ -56,11 +55,11 @@ public abstract class RetryParams {
   public abstract Duration getMaxRpcTimeout();
 
   public static Builder newBuilder() {
-    return new AutoValue_RetryParams.Builder();
+    return new AutoValue_RetrySettings.Builder();
   }
 
   public Builder toBuilder() {
-    return new AutoValue_RetryParams.Builder(this);
+    return new AutoValue_RetrySettings.Builder(this);
   }
 
   @AutoValue.Builder
@@ -76,10 +75,20 @@ public abstract static class Builder {
 
     public abstract Builder setTotalTimeout(Duration totalTimeout);
 
-    abstract RetryParams autoBuild();
+    public abstract Duration getInitialRetryDelay();
+    public abstract double getRetryDelayMultiplier();
+    public abstract Duration getMaxRetryDelay();
+
+    public abstract Duration getInitialRpcTimeout();
+    public abstract double getRpcTimeoutMultiplier();
+    public abstract Duration getMaxRpcTimeout();
+
+    public abstract Duration getTotalTimeout();
 
-    public RetryParams build() {
-      RetryParams params = autoBuild();
+    abstract RetrySettings autoBuild();
+
+    public RetrySettings build() {
+      RetrySettings params = autoBuild();
       if (params.getTotalTimeout().getMillis() < 0) {
         throw new IllegalStateException("total timeout must not be negative");
       }
@@ -100,5 +109,27 @@ public RetryParams build() {
       }
       return params;
     }
+
+    public RetrySettings.Builder merge(RetrySettings.Builder newSettings) {
+      if (newSettings.getInitialRetryDelay() != null) {
+        setInitialRetryDelay(newSettings.getInitialRetryDelay());
+      }
+      if (newSettings.getRetryDelayMultiplier() >= 1) {
+        setRetryDelayMultiplier(newSettings.getRetryDelayMultiplier());
+      }
+      if (newSettings.getMaxRetryDelay() != null) {
+        setMaxRetryDelay(newSettings.getMaxRetryDelay());
+      }
+      if (newSettings.getInitialRpcTimeout() != null) {
+        setInitialRpcTimeout(newSettings.getInitialRpcTimeout());
+      }
+      if (newSettings.getRpcTimeoutMultiplier() >= 1) {
+        setRpcTimeoutMultiplier(newSettings.getRpcTimeoutMultiplier());
+      }
+      if (newSettings.getMaxRpcTimeout() != null) {
+        setMaxRpcTimeout(newSettings.getMaxRpcTimeout());
+      }
+      return this;
+    }
   }
 }

src/main/java/com/google/api/gax/grpc/ApiCallSettings.java

@@ -31,57 +31,85 @@
 
 package com.google.api.gax.grpc;
 
-import com.google.api.gax.core.RetryParams;
+import com.google.api.gax.core.RetrySettings;
+import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Sets;
 
 import io.grpc.Status;
 
-import java.util.HashSet;
 import java.util.Set;
 
 /**
  * A settings class to configure an API method.
  */
 public class ApiCallSettings {
 
-  private Set<Status.Code> retryableCodes = new HashSet<>();
-  private RetryParams retryParams = null;
+  private final ImmutableSet<Status.Code> retryableCodes;
+  private final RetrySettings retrySettings;
 
-  /**
-   * Sets the retryable codes.
-   */
-  public ApiCallSettings setRetryableCodes(Set<Status.Code> retryableCodes) {
-    this.retryableCodes = retryableCodes;
-    return this;
+  public ImmutableSet<Status.Code> getRetryableCodes() {
+    return retryableCodes;
   }
 
-  /**
-   * Sets the retryable codes.
-   */
-  public ApiCallSettings setRetryableCodes(Status.Code... codes) {
-    this.retryableCodes = Sets.newHashSet(codes);
-    return this;
+  public RetrySettings getRetrySettings() {
+    return retrySettings;
   }
 
-  /**
-   * Gets the retryable codes.
-   */
-  public Set<Status.Code> getRetryableCodes() {
-    return retryableCodes;
+  public static Builder newBuilder() {
+    return new Builder();
+  }
+
+  public Builder toBuilder() {
+    return new Builder(this);
   }
 
-  /**
-   * Sets the retry params.
-   */
-  public ApiCallSettings setRetryParams(RetryParams retryParams) {
-    this.retryParams = retryParams;
-    return this;
+  protected ApiCallSettings(ImmutableSet<Status.Code> retryableCodes,
+                            RetrySettings retrySettings) {
+    this.retryableCodes = ImmutableSet.<Status.Code>copyOf(retryableCodes);
+    this.retrySettings = retrySettings;
   }
 
-  /**
-   * Returns the retry params.
-   */
-  public RetryParams getRetryParams() {
-    return retryParams;
+  public static class Builder {
+
+    private Set<Status.Code> retryableCodes;
+    private RetrySettings.Builder retrySettingsBuilder;
+
+    public Builder() {
+      retryableCodes = Sets.newHashSet();
+      retrySettingsBuilder = RetrySettings.newBuilder();
+    }
+
+    public Builder(ApiCallSettings apiCallSettings) {
+      setRetryableCodes(apiCallSettings.retryableCodes);
+      setRetrySettingsBuilder(apiCallSettings.getRetrySettings().toBuilder());
+    }
+
+    public Builder setRetryableCodes(Set<Status.Code> retryableCodes) {
+      this.retryableCodes = Sets.newHashSet(retryableCodes);
+      return this;
+    }
+
+    public Builder setRetryableCodes(Status.Code... codes) {
+      this.setRetryableCodes(Sets.newHashSet(codes));
+      return this;
+    }
+
+    public Builder setRetrySettingsBuilder(RetrySettings.Builder retrySettingsBuilder) {
+      this.retrySettingsBuilder = retrySettingsBuilder;
+      return this;
+    }
+
+    public Set<Status.Code> getRetryableCodes() {
+      return this.retryableCodes;
+    }
+
+    public RetrySettings.Builder getRetrySettingsBuilder() {
+      return this.retrySettingsBuilder;
+    }
+
+    public ApiCallSettings build() {
+      return new ApiCallSettings(ImmutableSet.<Status.Code>copyOf(retryableCodes),
+                                 retrySettingsBuilder.build());
+    }
   }
 }

src/main/java/com/google/api/gax/grpc/ApiCallSettingsTyped.java

@@ -0,0 +1,71 @@
+package com.google.api.gax.grpc;
+
+import com.google.api.gax.core.RetrySettings;
+import com.google.common.collect.ImmutableSet;
+
+import io.grpc.ManagedChannel;
+import io.grpc.MethodDescriptor;
+import io.grpc.Status;
+
+import java.io.IOException;
+import java.util.concurrent.ScheduledExecutorService;
+
+/**
+ * Package-private: Use other concrete settings classes instead of this class from outside of
+ * the package.
+ * A settings class with generic typing which can be used to configure an API method or create
+ * the method callable object. This class can be used as the base class that other concrete
+ * call settings classes inherit from.
+ */
+class ApiCallSettingsTyped<RequestT, ResponseT> extends ApiCallSettings {
+
+  private final MethodDescriptor<RequestT, ResponseT> methodDescriptor;
+
+  public MethodDescriptor<RequestT, ResponseT> getMethodDescriptor() {
+    return methodDescriptor;
+  }
+
+  protected ApiCallSettingsTyped(ImmutableSet<Status.Code> retryableCodes,
+                                 RetrySettings retrySettings,
+                                 MethodDescriptor<RequestT, ResponseT> methodDescriptor) {
+    super(retryableCodes, retrySettings);
+    this.methodDescriptor = methodDescriptor;
+  }
+
+  protected ApiCallable<RequestT, ResponseT> createBaseCallable(
+      ServiceApiSettings.Builder serviceSettingsBuilder) throws IOException {
+    ClientCallFactory<RequestT, ResponseT> clientCallFactory =
+        new DescriptorClientCallFactory<>(methodDescriptor);
+    ApiCallable<RequestT, ResponseT> callable =
+        new ApiCallable<>(new DirectCallable<>(clientCallFactory), this);
+    ManagedChannel channel = serviceSettingsBuilder.getOrBuildChannel();
+    ScheduledExecutorService executor = serviceSettingsBuilder.getOrBuildExecutor();
+    if (getRetryableCodes() != null) {
+      callable = callable.retryableOn(ImmutableSet.copyOf(getRetryableCodes()));
+    }
+    if (getRetrySettings() != null) {
+      callable = callable.retrying(getRetrySettings(), executor);
+    }
+    return callable.bind(channel);
+  }
+
+  public static class Builder<RequestT, ResponseT> extends ApiCallSettings.Builder {
+    private MethodDescriptor<RequestT, ResponseT> grpcMethodDescriptor;
+
+    public Builder(MethodDescriptor<RequestT, ResponseT> grpcMethodDescriptor) {
+      this.grpcMethodDescriptor = grpcMethodDescriptor;
+    }
+
+    public MethodDescriptor<RequestT, ResponseT> getMethodDescriptor() {
+      return grpcMethodDescriptor;
+    }
+
+    @Override
+    public ApiCallSettingsTyped<RequestT, ResponseT> build() {
+      return new ApiCallSettingsTyped<RequestT, ResponseT>(
+          ImmutableSet.<Status.Code>copyOf(getRetryableCodes()),
+          getRetrySettingsBuilder().build(),
+          grpcMethodDescriptor);
+    }
+  }
+}