public <T extends ToShapeId> Builder shapeId(T toShapeId) {
            this.shapeId = toShapeId == null ? null : toShapeId.toShapeId();
            return this;
        }
Sets the shape ID related to the event.

@param toShapeId Shape ID.
@param <T> Value to convert to a shape ID.
@return Returns the builder.
smithy-model/src/main/java/software/amazon/smithy/model/validation/ValidationEvent.java