问如何仅当JOLT中的字段不为空时进行映射

EN

[
  {
    "operation": "shift",
    "spec": {
      "isPoolPoint": {
        // match down into the values of "isPoolPoint"
        // if we match null, then do nothing
        "null": null,
        // match everything else
        "*": {
          // write what was matched to the output
          "$": "address[0].line2"
        }
      }
    }
  }
]

I wanted to ignore blank strings as well in addition to null values so I did below extra condition

[
  {
    "operation": "shift",
    "spec": {
      "isPoolPoint": {
         // OR operator below will care of empty string or null
        "|null": null,
        "*": {
          "$": "address[0].line2"
        }
      }
    }
  }
]