fork download 
  1. //package jdbcsetnulltest;
  2.  
  3. import java.sql.Connection;
  4. import java.sql.DriverManager;
  5. import java.sql.PreparedStatement;
  6. import java.sql.ResultSet;
  7. import java.sql.SQLException;
  8. import java.sql.Statement;
  9. import java.sql.Types;
  10. import java.util.UUID;
  11.  
  12. /**
  13.  *
  14.  * @author imaskar
  15.  */
  16. public class JdbcSetNullTest {
  17.  
  18.   /**
  19.    * @param args the command line arguments
  20.    * @throws java.lang.ClassNotFoundException
  21.    * @throws java.sql.SQLException
  22.    */
  23.   public static void main(String[] args) throws ClassNotFoundException, SQLException {
  24.     Class.forName("org.postgresql.Driver");
  25.     final String jdbcString = ""; //use your own
  26.     final String sql = "select 'ok' where null=null or (null is null)";
  27.     final String sqlBind = "select 'ok' where ?=? or (? is null)";
  28.     final String sqlBindCorrect = "select 'ok' where ?=? or (cast (? as uuid) is null)";
  29.     final Connection conn = DriverManager.getConnection(jdbcString);
  30.  
  31.     final UUID uuid = UUID.randomUUID();
  32.  
  33.     try (Statement st = conn.createStatement(); PreparedStatement stp = conn.prepareStatement(sqlBind);) {
  34.       ResultSet rs = st.executeQuery(sql);
  35.       printOut("Fixed", rs);
  36.  
  37.       try {
  38.         stp.setObject(1, uuid, Types.INTEGER);
  39.         stp.setNull(2, Types.INTEGER);
  40.         stp.setNull(3, Types.INTEGER);
  41.         rs = stp.executeQuery();
  42.         printOut("Prepared INTEGER", rs);
  43.       } catch (SQLException sQLException) {
  44.         System.out.println("Prepared INTEGER returned exception "+sQLException.getMessage());
  45.       }
  46.       try {
  47.         stp.clearParameters();
  48.         stp.setObject(1, uuid, Types.BINARY);
  49.         stp.setNull(2, Types.BINARY);
  50.         stp.setNull(3, Types.BINARY);
  51.         rs = stp.executeQuery();
  52.         printOut("Prepared BINARY", rs);
  53.       } catch (SQLException sQLException) {
  54.         System.out.println("Prepared BINARY returned exception "+sQLException.getMessage());
  55.       }
  56.       try {
  57.         stp.clearParameters();
  58.         stp.setNull(1, Types.BINARY);
  59.         stp.setNull(2, Types.BINARY);
  60.         stp.setNull(3, Types.BINARY);
  61.         rs = stp.executeQuery();
  62.         printOut("Prepared DOUBLE BINARY", rs);
  63.       } catch (SQLException sQLException) {
  64.         System.out.println("Prepared DOUBLE BINARY returned exception "+sQLException.getMessage());
  65.       }
  66.       try {
  67.         stp.clearParameters();
  68.         stp.setObject(1, uuid, Types.OTHER);
  69.         stp.setNull(2, Types.OTHER);
  70.         stp.setNull(3, Types.OTHER);
  71.         rs = stp.executeQuery();
  72.         printOut("Prepared OTHER", rs);
  73.       } catch (SQLException sQLException) {
  74.         System.out.println("Prepared OTHER returned exception "+sQLException.getMessage());
  75.       }
  76.       try {
  77.         stp.clearParameters();
  78.         stp.setObject(1, uuid.toString(), Types.VARCHAR);
  79.         stp.setNull(2, Types.VARCHAR);
  80.         stp.setNull(3, Types.VARCHAR);
  81.         rs = stp.executeQuery();
  82.         printOut("Prepared VARCHAR", rs);
  83.       } catch (SQLException sQLException) {
  84.         System.out.println("Prepared VARCHAR returned exception "+sQLException.getMessage());
  85.       }
  86.     }
  87.  
  88.   }
  89.  
  90.   private static void printOut(final String header, final ResultSet rs) throws SQLException {
  91.     System.out.print(header);
  92.     try {
  93.       while (rs.next()) {
  94.         System.out.print(": returned ");
  95.         System.out.println(rs.getString(1));
  96.       }      
  97.       rs.close();
  98.     } catch (SQLException sQLException) {
  99.         System.out.println("exception "+sQLException.getMessage());
  100.     }
  101.   }
  102.  
  103. }
  104.  
Compilation error #stdin compilation error #stdout 0s 0KB
comments (?)
stdin 
Standard input is empty
compilation info 
Main.java:16: error: class JdbcSetNullTest is public, should be declared in a file named JdbcSetNullTest.java
public class JdbcSetNullTest {
       ^
1 error
stdout 
Standard output is empty
https://ideone.com/W3sfhI
language:
Java (HotSpot 12)
created:
8 years ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!