package com.atlassian.scheduler.config;
   
   import com.atlassian.annotations.PublicApi;
   
   import javax.annotation.Nullable;
   import javax.annotation.concurrent.Immutable;
   import java.io.Serializable;
   
   import static com.atlassian.util.concurrent.Assertions.notNull;
  
  /**
   * A wrapper to distinguish job runner keys from simple strings and to make it easier
   * to avoid confusing them with Job IDs
   *
   * @since v1.0
   */
  @Immutable
  @PublicApi
  public final class JobRunnerKey implements Serializable, Comparable<JobRunnerKey> {
      private static final long serialVersionUID = 1L;
  
      /**
       * Wraps the provided string as a {@code JobRunnerKey}.
       * <p>
       * Although it is not necessary for correctness, it will usually make sense to create a single instance of
       * the {@code JobRunnerKey} and reuse it as a constant, as in:
       * </p>
       * <pre><code>
       *     private static final JobRunnerKey <strong>POP3_SERVICE</strong> = JobRunnerKey.of("com.example.plugin.Pop3Service");
       *
       *     // ...
       *
       *     private void registerJobRunner()
       *     {
       *         schedulerService.registerJobRunner(<strong>POP3_SERVICE</strong>, new Pop3JobRunner());
       *     }
       *
       *     private String scheduleJobWithGeneratedId(String cronExpression)
       *     {
       *         JobConfig jobConfig = JobConfig.forJobRunnerKey(<strong>POP3_SERVICE</strong>)
       *                  .withSchedule(Schedule.forCronExpression(cronExpression));
       *         return schedulerService.scheduleJobWithGeneratedId(jobConfig);
       *     }
       * </code></pre>
       *
       * @param key the job runner key, as a string
       * @return the wrapped job runner key
       */
      public static JobRunnerKey of(String key) {
          return new JobRunnerKey(key);
      }
  
  
      private final String key;
  
      private JobRunnerKey(final String key) {
          this.key = notNull("key", key);
      }
  
  
      @Override
      @SuppressWarnings("SimplifiableIfStatement")
      public boolean equals(@Nullable final Object o) {
          if (this == o) {
              return true;
          }
          return o != null
                  && o.getClass() == getClass()
                  && ((JobRunnerKey) o).key.equals(key);
      }
  
      @Override
      public int compareTo(final JobRunnerKey o) {
          return key.compareTo(o.key);
      }
  
      @Override
      public int hashCode() {
          return key.hashCode();
      }
  
      public String toString() {
          return key;
      }
  }