output: #fixed code
                                  @Test
      public void testExecuteAndFetchWithNulls(){
          String sql =
                  "create table testExecWithNullsTbl (" +
                  "id int identity primary key, " +
                  "text varchar(255), " +
                  "aNumber int, " +
                  "aLongNumber bigint)";
          try (Connection con = sql2o.open()) {
              con.createQuery(sql, "testExecuteAndFetchWithNulls").executeUpdate();
  
  
              Connection connection = sql2o.beginTransaction();
              Query insQuery = connection.createQuery("insert into testExecWithNullsTbl (text, aNumber, aLongNumber) values(:text, :number, :lnum)");
              insQuery.addParameter("text", "some text").addParameter("number", 2).addParameter("lnum", 10L).executeUpdate();
              insQuery.addParameter("text", "some text").addParameter("number", (Integer) null).addParameter("lnum", 10L).executeUpdate();
              insQuery.addParameter("text", (String) null).addParameter("number", 21).addParameter("lnum", (Long) null).executeUpdate();
              insQuery.addParameter("text", "some text").addParameter("number", 1221).addParameter("lnum", 10).executeUpdate();
              insQuery.addParameter("text", "some text").addParameter("number", 2311).addParameter("lnum", 12).executeUpdate();
              connection.commit();
  
              List<Entity> fetched = con.createQuery("select * from testExecWithNullsTbl").executeAndFetch(Entity.class);
  
              assertTrue(fetched.size() == 5);
              assertNull(fetched.get(2).text);
              assertNotNull(fetched.get(3).text);
  
              assertNull(fetched.get(1).aNumber);
              assertNotNull(fetched.get(2).aNumber);
  
              assertNull(fetched.get(2).aLongNumber);
              assertNotNull(fetched.get(3).aLongNumber);
          }
      }
input: #vulnerable code 
                                  @Test
      public void testExecuteAndFetchWithNulls(){
          String sql =
                  "create table testExecWithNullsTbl (" +
                  "id int identity primary key, " +
                  "text varchar(255), " +
                  "aNumber int, " +
                  "aLongNumber bigint)";
          sql2o.createQuery(sql, "testExecuteAndFetchWithNulls").executeUpdate();
  
  
          Connection connection = sql2o.beginTransaction();
          Query insQuery = connection.createQuery("insert into testExecWithNullsTbl (text, aNumber, aLongNumber) values(:text, :number, :lnum)");
          insQuery.addParameter("text", "some text").addParameter("number", 2).addParameter("lnum", 10L).executeUpdate();
          insQuery.addParameter("text", "some text").addParameter("number", (Integer)null).addParameter("lnum", 10L).executeUpdate();
          insQuery.addParameter("text", (String)null).addParameter("number", 21).addParameter("lnum", (Long)null).executeUpdate();
          insQuery.addParameter("text", "some text").addParameter("number", 1221).addParameter("lnum", 10).executeUpdate();
          insQuery.addParameter("text", "some text").addParameter("number", 2311).addParameter("lnum", 12).executeUpdate();
          connection.commit();
  
          List<Entity> fetched = sql2o.createQuery("select * from testExecWithNullsTbl").executeAndFetch(Entity.class);
  
          assertTrue(fetched.size() == 5);
          assertNull(fetched.get(2).text);
          assertNotNull(fetched.get(3).text);
  
          assertNull(fetched.get(1).aNumber);
          assertNotNull(fetched.get(2).aNumber);
  
          assertNull(fetched.get(2).aLongNumber);
          assertNotNull(fetched.get(3).aLongNumber);
      } 
                              #location 21 
                              #vulnerability type RESOURCE_LEAK