elasticsearch中 long与double类型的困惑

定义的long类型
"price": {"type": "long"}
 
传值23.59，可以成功；若改成"23.59"就会报错：],
"type": "mapper_parsing_exception",
"reason": "failed to parse [price]",
"caused_by": {

"type": "number_format_exception",
"reason": "For input string: "23.59""

}
 
long类型 为什么可以接收double值？