code: public Json schema(TypeInformation<Row> schemaType) {
  		Preconditions.checkNotNull(schemaType);
  		this.schema = TypeStringUtils.writeTypeInfo(schemaType);
  		this.jsonSchema = null;
  		this.deriveSchema = null;
  		return this;
  	}
docs: Sets the schema using type information.
  
  <p>JSON objects are represented as ROW types.
  
  <p>The schema might be nested.
  
  @param schemaType type information that describes the schema