[PECOBLR-839] Fixed getString for boolean column

src/main/java/com/databricks/jdbc/api/impl/converters/BitConverter.java

@@ -17,7 +17,17 @@ public boolean toBoolean(Object object) throws DatabricksSQLException {
       return Boolean.parseBoolean((String) object);
     }
     throw new DatabricksSQLException(
-        "Unsupported type for conversion to BIT: " + object.getClass(),
+        "Unsupported type for conversion to BIT: " + (object == null ? "null" : object.getClass()),
         DatabricksDriverErrorCode.UNSUPPORTED_OPERATION);
   }
+
+  @Override
+  public String toString(Object object) throws DatabricksSQLException {
+    if (object instanceof Boolean) {
+      return object.toString();
+    }
+    // For other types, fall back to the default behavior
+    throw new DatabricksSQLException(
+        "Unsupported String conversion operation", DatabricksDriverErrorCode.UNSUPPORTED_OPERATION);
+  }
 }

src/test/java/com/databricks/jdbc/api/impl/converters/BitConverterTest.java

@@ -0,0 +1,119 @@
+package com.databricks.jdbc.api.impl.converters;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+import com.databricks.jdbc.exception.DatabricksSQLException;
+import org.junit.jupiter.api.Test;
+
+public class BitConverterTest {
+
+  private final BitConverter bitConverter = new BitConverter();
+
+  @Test
+  public void testToStringWithBooleanTrue() throws DatabricksSQLException {
+    assertEquals("true", bitConverter.toString(true));
+  }
+
+  @Test
+  public void testToStringWithBooleanFalse() throws DatabricksSQLException {
+    assertEquals("false", bitConverter.toString(false));
+  }
+
+  @Test
+  public void testToStringWithBooleanObject() throws DatabricksSQLException {
+    Boolean trueObject = Boolean.TRUE;
+    Boolean falseObject = Boolean.FALSE;
+
+    assertEquals("true", bitConverter.toString(trueObject));
+    assertEquals("false", bitConverter.toString(falseObject));
+  }
+
+  @Test
+  public void testToStringWithUnsupportedType() {
+    DatabricksSQLException exception =
+        assertThrows(DatabricksSQLException.class, () -> bitConverter.toString("not a boolean"));
+
+    assertTrue(exception.getMessage().contains("Unsupported String conversion operation"));
+    assertEquals("UNSUPPORTED_OPERATION", exception.getSQLState());
+  }
+
+  @Test
+  public void testToStringWithNumber() {
+    DatabricksSQLException exception =
+        assertThrows(DatabricksSQLException.class, () -> bitConverter.toString(123));
+
+    assertTrue(exception.getMessage().contains("Unsupported String conversion operation"));
+    assertEquals("UNSUPPORTED_OPERATION", exception.getSQLState());
+  }
+
+  @Test
+  public void testToBooleanWithBooleanTrue() throws DatabricksSQLException {
+    assertTrue(bitConverter.toBoolean(true));
+  }
+
+  @Test
+  public void testToBooleanWithBooleanFalse() throws DatabricksSQLException {
+    assertFalse(bitConverter.toBoolean(false));
+  }
+
+  @Test
+  public void testToBooleanWithBooleanObject() throws DatabricksSQLException {
+    Boolean trueObject = Boolean.TRUE;
+    Boolean falseObject = Boolean.FALSE;
+
+    assertTrue(bitConverter.toBoolean(trueObject));
+    assertFalse(bitConverter.toBoolean(falseObject));
+  }
+
+  @Test
+  public void testToBooleanWithNumberZero() throws DatabricksSQLException {
+    assertFalse(bitConverter.toBoolean(0));
+    assertFalse(bitConverter.toBoolean(0L));
+    assertFalse(bitConverter.toBoolean(0.0f));
+    assertFalse(bitConverter.toBoolean(0.0));
+  }
+
+  @Test
+  public void testToBooleanWithNumberNonZero() throws DatabricksSQLException {
+    assertTrue(bitConverter.toBoolean(1));
+    assertTrue(bitConverter.toBoolean(-1));
+    assertTrue(bitConverter.toBoolean(42L));
+    assertTrue(bitConverter.toBoolean(3.14f));
+    assertTrue(bitConverter.toBoolean(2.71));
+  }
+
+  @Test
+  public void testToBooleanWithStringTrue() throws DatabricksSQLException {
+    assertTrue(bitConverter.toBoolean("true"));
+    assertTrue(bitConverter.toBoolean("TRUE"));
+    assertTrue(bitConverter.toBoolean("True"));
+  }
+
+  @Test
+  public void testToBooleanWithStringFalse() throws DatabricksSQLException {
+    assertFalse(bitConverter.toBoolean("false"));
+    assertFalse(bitConverter.toBoolean("FALSE"));
+    assertFalse(bitConverter.toBoolean("False"));
+    assertFalse(bitConverter.toBoolean("anything else"));
+  }
+
+  @Test
+  public void testToBooleanWithUnsupportedType() {
+    DatabricksSQLException exception =
+        assertThrows(DatabricksSQLException.class, () -> bitConverter.toBoolean(new Object()));
+
+    assertTrue(exception.getMessage().contains("Unsupported type for conversion to BIT"));
+    assertTrue(exception.getMessage().contains("Object"));
+    assertEquals("UNSUPPORTED_OPERATION", exception.getSQLState());
+  }
+
+  @Test
+  public void testToBooleanWithNull() {
+    DatabricksSQLException exception =
+        assertThrows(DatabricksSQLException.class, () -> bitConverter.toBoolean(null));
+
+    assertTrue(exception.getMessage().contains("Unsupported type for conversion to BIT"));
+    assertTrue(exception.getMessage().contains("null"));
+    assertEquals("UNSUPPORTED_OPERATION", exception.getSQLState());
+  }
+}