fe/src/main/java/org/apache/impala/catalog/events/MetastoreEventProcessorConfig.java

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package org.apache.impala.catalog.events;

import com.google.common.base.Preconditions;
import org.apache.impala.catalog.events.ConfigValidator.ValidationResult;

/**
 * Metastore configurations and their expected values for event processing.
 * These configs are validated before creating an instance of the event processor.
 * This is a super set of all the event processor configurations needed to be validated
 * and MetastoreShim version is used to get the actual sub-set of configurations to
 * validate depending on the hive version.
 */
public enum MetastoreEventProcessorConfig {
  ADD_THRIFT_OBJECTS("hive.metastore.notifications.add.thrift.objects", "true"),
  ALTER_NOTIFICATIONS_BASIC("hive.metastore.alter.notifications.basic", "false"),
  FIRE_EVENTS_FOR_DML("hive.metastore.dml.events", "true"),
  METASTORE_PARAMETER_EXCLUDE_PATTERNS(new EventPropertyRegexValidator(
      "hive.metastore.notification.parameters.exclude.patterns"));

  private final ConfigValidator validator_;

  MetastoreEventProcessorConfig(String configKey, String expectedValue) {
    Preconditions.checkNotNull(configKey);
    this.validator_ = new DefaultConfigValidator(configKey, expectedValue);
  }

  MetastoreEventProcessorConfig(ConfigValidator validator) {
    this.validator_ = Preconditions.checkNotNull(validator);
  }

  public ConfigValidator getValidator() {
    return validator_;
  }

  @Override
  public String toString() {
    return validator_.toString();
  }

  /**
   * Validates the given value for this Configuration
   * @param value
   * @return ValidationResult which indicates whether the validation is successful or
   * not. If the validation is not successful, provides a reason as to why the config
   * validation failed
   */
  public ValidationResult validate(String value) {
    return validator_.validate(value);
  }
}