fe/src/main/java/org/apache/impala/extdatasource/ApiVersion.java

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// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
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//
//   http://www.apache.org/licenses/LICENSE-2.0
//
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package org.apache.impala.extdatasource;

import org.apache.impala.extdatasource.v1.ExternalDataSource;
import com.google.common.base.Strings;

/**
 * Enumerates the valid versions of the {@link ExternalDataSource} API.
 */
public enum ApiVersion {
  V1(org.apache.impala.extdatasource.v1.ExternalDataSource.class);

  private final Class<?> apiInterface_;

  ApiVersion(Class<?> interfaceClass) {
    apiInterface_ = interfaceClass;
  }

  /**
   * Gets the {@link Class} for the interface this API version represents.
   */
  public Class<?> getApiInterface() { return apiInterface_; }

  /**
   * Parses the API version from the string. Is case-insensitive.
   * @return The value of the ApiVersion enum represented by the string or null
   *         if the string is not a valid ApiVersion.
   */
  public static ApiVersion parseApiVersion(String apiVersionString) {
    if (Strings.isNullOrEmpty(apiVersionString)) return null;
    try {
      return valueOf(apiVersionString.toUpperCase());
    } catch (IllegalArgumentException ex) {
      return null;
    }
  }
}