Java – invalid default value for field warning message from Avro?

I have an Avro architecture like this, where I will be is_ userid_ I want to set the default value to false, so I propose the following Avro architecture

{
   "type":"record","name":"hello","fields":[
      {
         "name":"u","type":[
            "string","null"
         ]
      },{
         "name":"p","type":"string"
      },{
         "name":"bu","type":"boolean"
      },{
         "name":"is_userid_present","type":"boolean","default":"false"
      }
   ]
}

But from the Avro code, I see this warning message –

[WARNING] Avro: Invalid default for field is_userid_present: "false" not a "boolean"

I'm not sure what I did wrong here? If I had such an Avro architecture, would there be any problems writing and reading data?

Solution

According to Avro docs, if you specify a default Boolean value, you can't make a string as you own it

Try this

{
     "name": "is_userid_present","type": "boolean","default": false
  }