db-derby-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Andreas Korneliussen (JIRA)" <derby-...@db.apache.org>
Subject [jira] Commented: (DERBY-1486) ERROR 40XD0 - When exracting Blob from a database
Date Wed, 12 Jul 2006 09:48:30 GMT
    [ http://issues.apache.org/jira/browse/DERBY-1486?page=comments#action_12420571 ] 

Andreas Korneliussen commented on DERBY-1486:
---------------------------------------------

When executing a statement in autocommit mode, the transaction will be committed. 

You are using forward-only, holdable result sets, which means that on commit, the result set
will not be closed, however since it is forward only, the current position of the cursor is
not valid, and you should issue next to get to a valid cursor position.

I would therefore expect the first example to fail, but not the second.
First:
if (rs.next()) {
      rs.getInt(1);
      
      readTable1(con, id);  <-- ---causes transaction commit,
      
      InputStream stream = rs.getBinaryStream(2);

      ObjectInputStream objStream = new ObjectInputStream(stream);

      Object obj = objStream.readObject();

      double[] array = (double[]) obj;

      System.out.println(array.length);
    } 
Second:
 while (rs.next()) {
      rs.getInt(1);

      InputStream stream = rs.getBinaryStream(2);

      ObjectInputStream objStream = new ObjectInputStream(stream);

      Object obj = objStream.readObject();

      double[] array = (double[]) obj;

      System.out.println(array.length);
      readTable1(con, id); <------- transaction commit
    } 

I have reproduced the problem. I found that if I modified the SELECT statement  from 
SELECT * FROM TABLE_2 to SELECT * FROM TABLE_2 WHERE ID>0, I was able to run the second
example without failures.




>  ERROR 40XD0 - When exracting Blob from a database
> --------------------------------------------------
>
>          Key: DERBY-1486
>          URL: http://issues.apache.org/jira/browse/DERBY-1486
>      Project: Derby
>         Type: Bug

>   Components: Miscellaneous
>     Versions: 10.1.2.1
>  Environment: Windows XP
>     Reporter: David Heath

>
> An exception occurs when extracting a Blob from a database. 
> The following code, will ALWAYS fail with the Exception:
> java.io.IOException: ERROR 40XD0: Container has been closed
>         at org.apache.derby.impl.store.raw.data.OverflowInputStream.fillByteHolder(Unknown
Source)
>         at org.apache.derby.impl.store.raw.data.BufferedByteHolderInputStream.read(Unknown
Source)
>         at java.io.DataInputStream.read(Unknown Source)
>         at java.io.FilterInputStream.read(Unknown Source)
>         at java.io.ObjectInputStream$PeekInputStream.read(Unknown Source)
>         at java.io.ObjectInputStream$PeekInputStream.readFully(Unknown Source)
>         at java.io.ObjectInputStream$BlockDataInputStream.readDoubles(Unknown Source)
>         at java.io.ObjectInputStream.readArray(Unknown Source)
>         at java.io.ObjectInputStream.readObject0(Unknown Source)
>         at java.io.ObjectInputStream.readObject(Unknown Source)
>         at BlobTest.readRows(BlobTest.java:81)
>         at BlobTest.main(BlobTest.java:23)
> CODE:
> import java.io.*;
> import java.sql.*;
> import java.util.*;
> public class BlobTest
> {
>   private static final String TABLE1 = "CREATE TABLE TABLE_1 ( "
>                                      + "ID INTEGER NOT NULL, "
>                                      + "COL_2 INTEGER NOT NULL, "
>                                      + "PRIMARY KEY (ID) )";
>   private static final String TABLE2 = "CREATE TABLE TABLE_2 ( "
>                                      + "ID INTEGER NOT NULL, "
>                                      + "COL_BLOB BLOB, "
>                                      + "PRIMARY KEY (ID) )";
>   public static void main(String... args) {
>     try {
>       createDBandTables();
>       Connection con = getConnection();
>       addRows(con, 10000, 1);
>       readRows(con, 1);
>       con.close();
>     }
>     catch(Exception exp) {
>       exp.printStackTrace();
>     }
>   }
>   private static void addRows(Connection con, int size, int id) 
>                                                          throws Exception
>   {
>     String sql = "INSERT INTO TABLE_1 VALUES(?, ?)";
>     PreparedStatement pstmt = con.prepareStatement(sql);
>     pstmt.setInt(1, id);
>     pstmt.setInt(2, 2);
>     pstmt.executeUpdate();
>     pstmt.close();
>     double[] array = new double[size];
>     array[size-1] = 1.23;
>     sql = "INSERT INTO TABLE_2 VALUES(?, ?)";
>     pstmt = con.prepareStatement(sql);
>     pstmt.setInt(1, id);
>     ByteArrayOutputStream byteStream = new ByteArrayOutputStream();
>     ObjectOutputStream objStream = new ObjectOutputStream(byteStream);
>     objStream.writeObject(array);         // Convert object to byte stream 
>     byte[] bytes = byteStream.toByteArray();
>     ByteArrayInputStream inStream = new ByteArrayInputStream(bytes);
>     pstmt.setBinaryStream(2, inStream, bytes.length);
>     pstmt.executeUpdate();
>     pstmt.close();
>   }
>   private static void readRows(Connection con, int id) throws Exception
>   {
>     String sql = "SELECT * FROM TABLE_2";
>     Statement stmt = con.createStatement();
>     ResultSet rs = stmt.executeQuery(sql);
>     if (rs.next()) {
>       rs.getInt(1);
>       readTable1(con, id);
>       InputStream stream = rs.getBinaryStream(2);
>       ObjectInputStream objStream = new ObjectInputStream(stream);
>       Object obj = objStream.readObject();   // FAILS HERE
>       double[] array = (double[]) obj;
>       System.out.println(array.length);
>     }
>     rs.close();
>     stmt.close();
>   }
>   private static void readTable1(Connection con, int id) throws Exception {
>     String sql = "SELECT ID FROM TABLE_1 WHERE ID=" + id;    
>     Statement stmt = con.createStatement();
>     ResultSet rs = stmt.executeQuery(sql);
>     if (rs.next()) {
>     }
>     rs.close();
>     stmt.close();
>   }
>   
>   private static Connection getConnection() throws Exception {
>     String driver="org.apache.derby.jdbc.EmbeddedDriver";
>     Properties p = System.getProperties();
>     p.put("derby.system.home", "C:\\databases\\sample");
>     
>     Class.forName(driver);
>     String url = "jdbc:derby:derbyBlob";
>     Connection con = DriverManager.getConnection(url);
>     return con;
>   }
>   private static void createDBandTables() throws Exception {
>     String driver="org.apache.derby.jdbc.EmbeddedDriver";
>     Properties p = System.getProperties();
>     p.put("derby.system.home", "C:\\databases\\sample");
>     
>     Class.forName(driver);
>     String url = "jdbc:derby:derbyBlob;create=true";
>     Connection con = DriverManager.getConnection(url);
>     Statement stmt = con.createStatement();
>     stmt.execute(TABLE1);
>     stmt.execute(TABLE2);
>     stmt.close();
>     con.close();
>   }
> }
> The Exception DOES NOT occur if call to readTable1() is not made.
> The Exception DOES NOT occur if the size of the Blob is reduced - for example calling:
>       addRows(con, 1000, 1);
> This is a show stopper.
> Output from: java org.apache.derby.tools.sysinfo
> ------------------ Java Information ------------------
> Java Version:    1.5.0_05
> Java Vendor:     Sun Microsystems Inc.
> Java home:       C:\Program Files\Java\jre1.5.0_05
> Java classpath:  C:\tools\derby\db-derby-10.1.2.1-bin\lib\derby.jar;C:\tools\der
> by\db-derby-10.1.2.1-bin\lib\derbytools.jar;
> OS name:         Windows XP
> OS architecture: x86
> OS version:      5.1
> Java user name:  David
> Java user home:  C:\Documents and Settings\David
> Java user dir:   C:\david\novice\derby
> java.specification.name: Java Platform API Specification
> java.specification.version: 1.5
> --------- Derby Information --------
> JRE - JDBC: J2SE 5.0 - JDBC 3.0
> [C:\tools\derby\db-derby-10.1.2.1-bin\lib\derby.jar] 10.1.2.1 - (330608)
> [C:\tools\derby\db-derby-10.1.2.1-bin\lib\derbytools.jar] 10.1.2.1 - (330608)
> ------------------------------------------------------
> ----------------- Locale Information -----------------
> ------------------------------------------------------

-- 
This message is automatically generated by JIRA.
-
If you think it was sent incorrectly contact one of the administrators:
   http://issues.apache.org/jira/secure/Administrators.jspa
-
For more information on JIRA, see:
   http://www.atlassian.com/software/jira


Mime
View raw message