Spark - ReturnStatementInClosureException: Return statements aren‘t allowed in Spark closures

I. Introduction

When Spark uses RDD to call the Filter function, the driver side gets stuck and reports the error ReturnStatementInClosureException: Return statements aren't allowed in Spark closures, that is, the return function cannot be used in the closure:

2. Usage scenarios

The return method is used when using the rdd.filter method to filter the id, resulting in the above error:

    rdd.filter(arr => {
       val id = arr(0)

       val l = id.length()
       if (l <= 8) return false

       if (id.startsWith("1")) {
           true
       } else {
           false
       }
     })

amendment:

The return keyword is not used in the closure function.

    rdd.filter(arr => {
        val id = arr(0)

        val l = id.length()

        if (l <= 8) {
            false
        } else if (id.startsWith("1")) {
            true
        } else {
            false
        }
    })