I am using the below code to generate some output file , the sample code is not showing the values however the count is correct

    public static void main(String[] args) {
    SparkSession sess = SparkSession.builder().master("local[2]").getOrCreate();
    List<String> x = new ArrayList<>();
    for(int i=0 ; i <100; i++)
        x.add("random"+i);
    MapFunction<String , Position> mapFunction = new MapFunction<String, Position>() {
        @Override
        public Position call(String s) throws Exception {
            Position p = new Position();
            p.setPid(s);
            return p;
        }
    };
    Dataset<String> dataset = sess.createDataset(x, Encoders.STRING());
    Dataset<Position> map = dataset.map(mapFunction, Encoders.bean(Position.class));
    map.show();
}

If i am using any primitive type it is working , for any custom java class it is not working , spark version is 2.4.5 can not change this version the Pojo is having only one field for test ,

Please help me to understand why this simple this is not workig

output like below

++
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++
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