How do I convert column of unix epoch to Date in Apache spark DataFrame using Java?

After checking spark dataframe api and sql function, I come out below snippet:

DateFrame df = sqlContext.read().json("MY_JSON_DATA_FILE");

DataFrame df_DateConverted = df.withColumn("creationDt", from_unixtime(stackoverflow_Tags.col("creationDate").divide(1000)));

The reason why "creationDate" column is divided by "1000" is cause the TimeUnit is different. The orgin "creationDate" is unix epoch in "milli-second", however spark sql "from_unixtime" is designed to handle unix epoch in "second".

pyspark converts from Unix epoch milliseconds to dataframe timestamp

df.select(from_unixtime((df.my_date_column.cast('bigint')/1000)).cast('timestamp').alias('my_date_column'))