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Scala Matching Option [(A, B)]

I am writing a Java code generator.

I have an immutable Map that contains a map from java.sql.Types[Int] to a tuple (String, String), where the first value is a Java type and the second is a Java package from which the type should be imported if it is not imported by default ( java.lang):

val SqlTypesToJavaTypeNames =
    Map(Types.BIGINT -> ("Long", None),
        Types.BINARY -> ("byte[]", None),
        Types.BIT -> ("Boolean", None),
        Types.BOOLEAN -> ("Boolean", None),
        Types.CHAR -> ("String", None),
        Types.DATE -> ("Date", Some("java.sql.Date")),
        Types.DECIMAL -> ("BigDecimal", Some("java.math.BigDecimal")),
        Types.DOUBLE -> ("Double", None),
        Types.FLOAT -> ("Float", None),
        Types.INTEGER -> ("Integer", None),
        Types.LONGNVARCHAR -> ("String", None),
        Types.LONGVARCHAR -> ("String", None),
        Types.NCHAR -> ("String", None),
        Types.NUMERIC -> ("BigDecimal", None),
        Types.NVARCHAR -> ("String", None),
        Types.REAL -> ("Float", None),
        Types.SMALLINT -> ("Short", None),
        Types.SQLXML -> ("String", None),
        Types.TIME -> ("Time", Some("java.sql.Time")),
        Types.TIMESTAMP -> ("Timestamp", Some("java.sql.Timestamp")),
        Types.TINYINT -> ("Byte", None),
        Types.VARCHAR -> ("String", None))

I am trying to match the image when searching for this map, where dataTypeis the value java.sql.Typesfrom the database metadata:

val (javaType, importType) =
  SqlTypesToJavaTypeNames.get(dataType) match {
    case Some(jType, Some(iType)) => (jType, iType)
    case Some(jType, None) => (jType, null)
    case None => throw new IllegalStateException("Unknown translation to Java type for SQL type " + dataType)
  }

The compiler gives me an error on the first case(starts with case Some(jType, Some(iType))):error: wrong number of arguments for <none>: (x: (java.lang.String, Option[java.lang.String]))Some[(java.lang.String, Option[java.lang.String])]

I'm not sure what is wrong.

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2 answers

Some , . , :

case Some( (jType, Some(iType)) ) => (jType, iType)

, , , , :

case Some(jType -> Some(iType)) => (jType, iType)

UPDATE

, , , :

val tpes = SqlTypesToJavaTypeNames.get(dataType)
val (javaType, importType) =
  tpes map { case (a,b) => (a, b.orNull) } getOrElse { throw ... }
+11

( Option[(A, B)]:

case Some( (jType, Some(iType)) ) => 
case Some( (jType, _) )           =>
case None                         =>

, :

SqlTypesToJavaTypeNames.get(dataType) map { case (jType, maybeIType) => jType -> maybeIType.orNull } getOrElse error("Unmapped : " + dataType)
+6

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