code: @Override
  	public void setReference(Record reference) {
  		for (int i = 0; i < this.keyFields1.length; i++) {
  			if (!reference.getFieldInto(this.keyFields1[i], this.keyHolders1[i])) {
  				throw new NullKeyFieldException(this.keyFields1[i]);
  			}
  		}
  	}
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