How to read BLOBs as "Java.io.Reader"

Hello,
I have a problem dealing with BLOBs in JDBC. I want to get a BLOB as a "java.io.Reader". I have written the following code:
class Db_templates {
public static Reader select(int tpl_id) {
try {
Connection connection = ... ;
Reader retour = null;
String strSQL = "SELECT tpl_blob FROM templates WHERE tpl_id = ?";
PreparedStatement ps = connection.prepareStatement(strSQL);
ps.setInt(1, tpl_id);
ResultSet rset = ps.executeQuery();
if (rset.next()) {
oracle.sql.BLOB blob = (BLOB)rset.getObject(1);
retour = blob.characterStreamValue();
rset.close();
ps.close();
connection.close();
return retour;
} catch (SQLException e) {
return null;
Then I try to call this method in a JSP file (Tomcat 4.0 as JSP container) with the following lines:
Reader i = Db_templates.select(42);
out.println(i.ready());
char buf[] = new char[1000];
try {
int retour = i.read(buf, 1, 900);
} catch (IOException e) {
out.println(e.toString());
The method i.ready() returns false with no IOException thrown.
The method i.read() fails to execute with the following errors:
java.lang.NullPointerException
at oracle.sql.LobPlsqlUtil.plsql_read(LobPlsqlUtil.java:911)
at oracle.sql.LobPlsqlUtil.plsql_read(LobPlsqlUtil.java:52)
at oracle.jdbc.dbaccess.DBAccess.lobRead(DBAccess.java:658)
at oracle.sql.LobDBAccessImpl.getBytes(LobDBAccessImpl.java:95)
at oracle.sql.BLOB.getBytes(BLOB.java:175)
at oracle.jdbc.driver.OracleBlobInputStream.needBytes(OracleBlobInputStream.java:126)
at oracle.jdbc.driver.OracleBufferedStream.read(OracleBufferedStream.java:108)
at oracle.jdbc.driver.OracleConversionReader.needChars(OracleConversionReader.java:151)
at oracle.jdbc.driver.OracleConversionReader.read(OracleConversionReader.java:119)
at org.apache.jsp.essai2$jsp._jspService(essai2$jsp.java:87)
Any ideas?
Thanks,
Nicolas

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If you are accustomed to the down arrow key moving among search results so you can press the Enter key to load them, and you are using Google, this is due to a script in the results page intercepting those keys and changing what they normally do.
I have only tested Windows myself, so I don't know whether this is generally available when using Google in your distribution of Linux. If it is, then the question would be: why not on your Firefox? Hmm...

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