RequestMetadataCallback.java

/*
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 * in the documentation and/or other materials provided with the
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 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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package com.google.auth;

import java.util.List;
import java.util.Map;

/**
 * The callback that receives the result of the asynchronous {@link
 * Credentials#getRequestMetadata(java.net.URI, java.util.concurrent.Executor,
 * RequestMetadataCallback)}. Exactly one method should be called.
 */
public interface RequestMetadataCallback {
  /**
   * Called when metadata is successfully produced.
   *
   * @param metadata Metadata returned for the request.
   */
  void onSuccess(Map<String, List<String>> metadata);

  /**
   * Called when metadata generation failed.
   *
   * @param exception The thrown exception which caused the request metadata fetch to fail.
   */
  void onFailure(Throwable exception);
}