GrpcCallSettings.java

/*
 * Copyright 2017 Google LLC
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 * modification, are permitted provided that the following conditions are
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 * notice, this list of conditions and the following disclaimer.
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 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
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 * contributors may be used to endorse or promote products derived from
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 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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package com.google.api.gax.grpc;

import com.google.api.core.BetaApi;
import com.google.api.gax.rpc.RequestParamsExtractor;
import io.grpc.MethodDescriptor;

/** Grpc-specific settings for creating callables. */
@BetaApi("The surface for use by generated code is not stable yet and may change in the future.")
public class GrpcCallSettings<RequestT, ResponseT> {
  private final MethodDescriptor<RequestT, ResponseT> methodDescriptor;
  private final RequestParamsExtractor<RequestT> paramsExtractor;
  private final boolean alwaysAwaitTrailers;

  private GrpcCallSettings(Builder builder) {
    this.methodDescriptor = builder.methodDescriptor;
    this.paramsExtractor = builder.paramsExtractor;
    this.alwaysAwaitTrailers = builder.shouldAwaitTrailers;
  }

  public MethodDescriptor<RequestT, ResponseT> getMethodDescriptor() {
    return methodDescriptor;
  }

  @BetaApi
  public RequestParamsExtractor<RequestT> getParamsExtractor() {
    return paramsExtractor;
  }

  @BetaApi
  public boolean shouldAwaitTrailers() {
    return alwaysAwaitTrailers;
  }

  public static <RequestT, ResponseT> Builder<RequestT, ResponseT> newBuilder() {
    return new Builder<RequestT, ResponseT>().setShouldAwaitTrailers(true);
  }

  public static <RequestT, ResponseT> GrpcCallSettings<RequestT, ResponseT> create(
      MethodDescriptor<RequestT, ResponseT> methodDescriptor) {
    return GrpcCallSettings.<RequestT, ResponseT>newBuilder()
        .setMethodDescriptor(methodDescriptor)
        .build();
  }

  public Builder toBuilder() {
    return new Builder<>(this);
  }

  public static class Builder<RequestT, ResponseT> {
    private MethodDescriptor<RequestT, ResponseT> methodDescriptor;
    private RequestParamsExtractor<RequestT> paramsExtractor;
    private boolean shouldAwaitTrailers;

    private Builder() {}

    private Builder(GrpcCallSettings<RequestT, ResponseT> settings) {
      this.methodDescriptor = settings.methodDescriptor;
      this.paramsExtractor = settings.paramsExtractor;
      this.shouldAwaitTrailers = settings.alwaysAwaitTrailers;
    }

    public Builder<RequestT, ResponseT> setMethodDescriptor(
        MethodDescriptor<RequestT, ResponseT> methodDescriptor) {
      this.methodDescriptor = methodDescriptor;
      return this;
    }

    @BetaApi
    public Builder<RequestT, ResponseT> setParamsExtractor(
        RequestParamsExtractor<RequestT> paramsExtractor) {
      this.paramsExtractor = paramsExtractor;
      return this;
    }

    @BetaApi
    public Builder<RequestT, ResponseT> setShouldAwaitTrailers(boolean b) {
      this.shouldAwaitTrailers = b;
      return this;
    }

    public GrpcCallSettings<RequestT, ResponseT> build() {
      return new GrpcCallSettings<>(this);
    }
  }
}