[KYUUBI #1784] Fix float types lose precision

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### _Why are the changes needed?_
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close #1784

### _How was this patch tested?_
- [x] Add some test cases that check the changes thoroughly including negative and positive cases if possible

- [ ] Add screenshots for manual tests if appropriate

- [ ] [Run test](https://kyuubi.readthedocs.io/en/latest/develop_tools/testing.html#running-tests) locally before make a pull request

Closes #1790 from cfmcgrady/kyuubi-1784.

Closes #1784

f6c7dae [Fu Chen] fix row-based row set
89e72b7 [Fu Chen] fix ut
cef54bc [Fu Chen] fix float types lose precision

Authored-by: Fu Chen <cfmcgrady@gmail.com>
Signed-off-by: ulysses-you <ulyssesyou@apache.org>

externals/kyuubi-spark-sql-engine/src/main/scala/org/apache/kyuubi/engine/spark/schema/RowSet.scala

@@ -90,7 +90,7 @@ object RowSet {
 
       case FloatType =>
         val values = getOrSetAsNull[java.lang.Float](rows, ordinal, nulls, 0.toFloat)
-          .asScala.map(n => java.lang.Double.valueOf(n.toDouble)).asJava
+          .asScala.map(n => java.lang.Double.valueOf(n.toString)).asJava
         TColumn.doubleVal(new TDoubleColumn(values, nulls))
 
       case DoubleType =>
@@ -176,7 +176,10 @@ object RowSet {
 
       case FloatType =>
         val tDoubleValue = new TDoubleValue
-        if (!row.isNullAt(ordinal)) tDoubleValue.setValue(row.getFloat(ordinal))
+        if (!row.isNullAt(ordinal)) {
+          val doubleValue = java.lang.Double.valueOf(row.getFloat(ordinal).toString)
+          tDoubleValue.setValue(doubleValue)
+        }
         TColumnValue.doubleVal(tDoubleValue)
 
       case DoubleType =>

externals/kyuubi-spark-sql-engine/src/test/scala/org/apache/kyuubi/engine/spark/schema/RowSetSuite.scala

@@ -142,7 +142,7 @@ class RowSetSuite extends KyuubiFunSuite {
     val floatCol = cols.next().getDoubleVal
     floatCol.getValues.asScala.zipWithIndex.foreach {
       case (b, 11) => assert(b === 0)
-      case (b, i) => assert(b === java.lang.Float.valueOf(s"$i.$i"))
+      case (b, i) => assert(b.toFloat === java.lang.Float.valueOf(s"$i.$i"))
     }
 
     val doubleCol = cols.next().getDoubleVal
@@ -226,7 +226,7 @@ class RowSetSuite extends KyuubiFunSuite {
 
     val r4 = iter.next().getColVals
     assert(r4.get(4).getI64Val.getValue === 3)
-    assert(r4.get(5).getDoubleVal.getValue === 3.3f)
+    assert(r4.get(5).getDoubleVal.getValue.toFloat === 3.3f)
 
     val r5 = iter.next().getColVals
     assert(r5.get(6).getDoubleVal.getValue === 4.4d)

kyuubi-server/src/test/scala/org/apache/kyuubi/engine/spark/SparkSqlEngineSuite.scala

@@ -124,5 +124,13 @@ class SparkSqlEngineSuite extends WithKyuubiServer with HiveJDBCTestHelper {
     }
   }
 
+  test("KYUUBI-1784: float types should not lose precision") {
+    withJdbcStatement() { statement =>
+      val resultSet = statement.executeQuery("SELECT cast(0.1 as float) AS col")
+      assert(resultSet.next())
+      assert(resultSet.getString("col") == "0.1")
+    }
+  }
+
   override protected def jdbcUrl: String = getJdbcUrl
 }