扫描程序（文件（字符串路径名））提供FileNotFoundException，而Scanner（文件（URI uri））不适用于相同的资源。为什么？

Question

新扫描程序（文件）中的FileNotFoundException失败：

// Option 1: peopleDF.write.parquet("people.parquet")
//Option 2:
 peopleDF.write.format("parquet").mode(SaveMode.Append).saveAsTable("people.parquet")

// Read in the parquet file created above
val parquetFile = spark.read.parquet("people.parquet")

//Parquet files can also be registered as tables and then used in SQL statements.
parquetFile.registerTempTable("parquetFile")
val teenagers = sqlContext.sql("SELECT * FROM people.parquet")

但这样运行正常，没有任何异常（同一个包中的类）：

public class Ex1 {

public static void main(String[] args) {

    // boot.txt -is in its own "resource" source folder in Eclipse
    String fileName = Ex1.class.getResource("/boot.txt").toExternalForm();
    File file = new File(fileName); // File (String pathname) ctor
    Scanner sc;

    try {
        sc = new Scanner(file); // FileNotFoundException here
    } catch (FileNotFoundException e) {         
        e.printStackTrace();
    }       
}

有什么问题

public class Ex2 {

public static void main(String[] args) {

    URL fileURL = Ex2.class.getResource("/boot.txt");
    Scanner sc;

    try {
        File file = new File(fileURL.toURI());  
        sc = new Scanner(file);  // fine!
    } catch (FileNotFoundException | URISyntaxException e) {            
        e.printStackTrace();
    }       
}

This导致Scanner ctors之间的“奇怪”差异，但没有回答这个问题......