code: void acceptAsSourceSegment(MergeSegmentOperation operation) {
          Exceptions.checkArgument(this.id == operation.getSourceSegmentId(),
                  "operation", "Invalid Operation Source Segment Id.");
  
          this.sealed = true;
          this.merged = true;
          this.isChanged = true;
      }
docs: Accepts the given operation as a Source Segment.
  
  @param operation The operation.
  @throws IllegalArgumentException If the operation is for a different Segment.