code: @Override
  	public void configure(Configuration parameters) {
  
  		// enforce sequential configuration() calls
  		synchronized (CONFIGURE_MUTEX) {
  			// configure MR InputFormat if necessary
  			if (this.mapredInputFormat instanceof Configurable) {
  				((Configurable) this.mapredInputFormat).setConf(this.jobConf);
  			} else if (this.mapredInputFormat instanceof JobConfigurable) {
  				((JobConfigurable) this.mapredInputFormat).configure(this.jobConf);
  			}
  		}
  	}
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