Major Description
Cast expression only supports a subset of type casts. We should just implement all the possible casts so we don't need to fall back to non-codegen mode.
See Cast.scala
override def genCode(ctx: CodeGenContext, ev: GeneratedExpressionCode): String = { // TODO: Add support for more data types. (child.dataType, dataType) match { case (BinaryType, StringType) => defineCodeGen (ctx, ev, c => s"${ctx.stringType}.fromBytes($c)") case (DateType, StringType) => defineCodeGen(ctx, ev, c => s"""${ctx.stringType}.fromString( org.apache.spark.sql.catalyst.util.DateTimeUtils.dateToString($c))""") case (TimestampType, StringType) => defineCodeGen(ctx, ev, c => s"""${ctx.stringType}.fromString( org.apache.spark.sql.catalyst.util.DateTimeUtils.timestampToString($c))""") case (_, StringType) => defineCodeGen(ctx, ev, c => s"${ctx.stringType}.fromString(String.valueOf($c))") // fallback for DecimalType, this must be before other numeric types case (_, dt: DecimalType) => super.genCode(ctx, ev) case (BooleanType, dt: NumericType) => defineCodeGen(ctx, ev, c => s"(${ctx.javaType(dt)})($c ? 1 : 0)") case (dt: DecimalType, BooleanType) => defineCodeGen(ctx, ev, c => s"!$c.isZero()") case (dt: NumericType, BooleanType) => defineCodeGen(ctx, ev, c => s"$c != 0") case (_: DecimalType, dt: NumericType) => defineCodeGen(ctx, ev, c => s"($c).to${ctx.primitiveTypeName(dt)}()") case (_: NumericType, dt: NumericType) => defineCodeGen(ctx, ev, c => s"(${ctx.javaType(dt)})($c)") case other => super.genCode(ctx, ev) } }
