Class Loading in JavaScript

Hi Folks,
I'm using OS BIRT 2.6.2.
I have 3 lines of JavaScript in Initialize which gets an error. 3 lines are:

//

importPackage(Packages.com.mysql.jdbc);
java.lang.Class.forName( "sun.jdbc.odbc.JdbcOdbcDriver" ).newInstance(); // Line works OK.
java.lang.Class.forName( "com.mysql.jdbc.Driver" ); // Line Fails
//

I'm trying to load the class Driver for mySQL so I can update a row in the DB to say report is done.
Getting the ODBC driver from rt.jar works fine. (Line 2)
Anyone encountered this issue? And solutions about class loading in BIRT?
Thanks.
Milt.

--- Additional Info.
Here's all the places I added the JAR file:

A) Windows -> Prefs -> Report Design -> Classpath

Resources -> Jar Files to the report

C) I copied jar to all of the following folders:
-) C:\Program Files\Common Files\Actuate\10.0\JRE160\lib
-) C:\Program Files\Common Files\Actuate\10.0\JDK160\lib
-) C:\Program Files\BIRTOS262\eclipse\dropins
-) C:\Program Files\BIRTOS262\eclipse\plugins\org.eclipse.birt.report.data.oda.jdbc_2.6.2.r262_v20110127\drivers

Error Message + Stack trace.

ReportDesign (id = 1):
+ There are errors evaluating script "
importPackage(Packages.com.mysql.jdbc.*);
java.lang.Class.forName( "sun.jdbc.odbc.JdbcOdbcDriver" ).newInstance();
java.lang.Class.forName( "com.mysql.jdbc.Driver" );

Wrapped java.lang.ClassNotFoundException: com.mysql.jdbc.Driver (/report/method[@name="initialize"]#6)
birt.core.JavascriptCommonError ( 1 time(s) )

detail : org.eclipse.birt.report.engine.api.EngineException: There are errors evaluating script "
importPackage(Packages.com.mysql.jdbc.*);
java.lang.Class.forName( "sun.jdbc.odbc.JdbcOdbcDriver" ).newInstance();
java.lang.Class.forName( "com.mysql.jdbc.Driver" );

Wrapped java.lang.ClassNotFoundException: com.mysql.jdbc.Driver (/report/method[@name="initialize"]#6)
at org.eclipse.birt.report.engine.script.internal.ScriptExecutor.addException(ScriptExecutor.java:158)
at

org.eclipse.birt.report.engine.script.internal.ReportScriptExecutor.handleInitialize(ReportScriptExecutor.java:53)
at org.eclipse.birt.report.engine.api.impl.EngineTask.loadDesign(EngineTask.java:1766)
at org.eclipse.birt.report.engine.api.impl.RunAndRenderTask.doRun(RunAndRenderTask.java:98)
at org.eclipse.birt.report.engine.api.impl.RunAndRenderTask.run(RunAndRenderTask.java:77)
at org.eclipse.birt.report.service.ReportEngineService.runAndRenderReport(ReportEngineService.java:928)
at org.eclipse.birt.report.service.BirtViewerReportService.runAndRenderReport(BirtViewerReportService.java:973)
at

org.eclipse.birt.report.service.actionhandler.BirtGetPageAllActionHandler.__execute(BirtGetPageAllActionHandler.java:131)
at

org.eclipse.birt.report.service.actionhandler.AbstractBaseActionHandler.execute(AbstractBaseActionHandler.java:90)
at

org.eclipse.birt.report.soapengine.processor.AbstractBaseDocumentProcessor.__executeAction(AbstractBaseDocumentProcessor.jav

a:47)
at

org.eclipse.birt.report.soapengine.processor.AbstractBaseComponentProcessor.executeAction(AbstractBaseComponentProcessor.jav

a:143)
at

org.eclipse.birt.report.soapengine.processor.BirtDocumentProcessor.handleGetPageAll(BirtDocumentProcessor.java:183)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at

org.eclipse.birt.report.soapengine.processor.AbstractBaseComponentProcessor.process(AbstractBaseComponentProcessor.java:112)
at org.eclipse.birt.report.soapengine.endpoint.BirtSoapBindingImpl.getUpdatedObjects(BirtSoapBindingImpl.java:66)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.axis.providers.java.RPCProvider.invokeMethod(RPCProvider.java:397)
at org.apache.axis.providers.java.RPCProvider.processMessage(RPCProvider.java:186)
at org.apache.axis.providers.java.JavaProvider.invoke(JavaProvider.java:323)
at org.apache.axis.strategies.InvocationStrategy.visit(InvocationStrategy.java:32)
at org.apache.axis.SimpleChain.doVisiting(SimpleChain.java:118)
at org.apache.axis.SimpleChain.invoke(SimpleChain.java:83)
at org.apache.axis.handlers.soap.SOAPService.invoke(SOAPService.java:454)
at org.apache.axis.server.AxisServer.invoke(AxisServer.java:281)
at org.apache.axis.transport.http.AxisServlet.doPost(AxisServlet.java:699)
at

org.eclipse.birt.report.servlet.BirtSoapMessageDispatcherServlet.doPost(BirtSoapMessageDispatcherServlet.java:265)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
at org.apache.axis.transport.http.AxisServletBase.service(AxisServletBase.java:327)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)
at

org.eclipse.birt.report.servlet.BirtSoapMessageDispatcherServlet.service(BirtSoapMessageDispatcherServlet.java:122)
at org.eclipse.equinox.http.registry.internal.ServletManager$ServletWrapper.service(ServletManager.java:180)
at org.eclipse.equinox.http.servlet.internal.ServletRegistration.service(ServletRegistration.java:61)
at org.eclipse.equinox.http.servlet.internal.ProxyServlet.processAlias(ProxyServlet.java:126)
at org.eclipse.equinox.http.servlet.internal.ProxyServlet.service(ProxyServlet.java:60)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)
at

org.eclipse.equinox.http.jetty.internal.HttpServerManager$InternalHttpServiceServlet.service(HttpServerManager.java:318)
at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)
at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:390)
at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)
at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:765)
at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
at org.mortbay.jetty.Server.handle(Server.java:326)
at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)
at org.mortbay.jetty.HttpConnection$RequestHandler.content(HttpConnection.java:939)
at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:756)
at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:212)
at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)
at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:409)
at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)
Caused by: org.eclipse.birt.core.exception.CoreException: There are errors evaluating script "
importPackage(Packages.com.mysql.jdbc.*);

java.lang.Class.forName( "sun.jdbc.odbc.JdbcOdbcDriver" ).newInstance();

java.lang.Class.forName( "com.mysql.jdbc.Driver" );

":
Wrapped java.lang.ClassNotFoundException: com.mysql.jdbc.Driver (/report/method[@name="initialize"]#6)
at org.eclipse.birt.report.engine.javascript.JavascriptEngine.evaluate(JavascriptEngine.java:287)
at org.eclipse.birt.core.script.ScriptContext.evaluate(ScriptContext.java:154)
at org.eclipse.birt.report.engine.executor.ExecutionContext.evaluate(ExecutionContext.java:772)
at org.eclipse.birt.report.engine.executor.ExecutionContext.evaluate(ExecutionContext.java:701)
at org.eclipse.birt.report.engine.script.internal.ScriptExecutor.handleScriptInternal(ScriptExecutor.java:61)
at org.eclipse.birt.report.engine.script.internal.ScriptExecutor.handleScript(ScriptExecutor.java:48)
at

org.eclipse.birt.report.engine.script.internal.ReportScriptExecutor.handleInitialize(ReportScriptExecutor.java:44)
... 53 more
Caused by: org.mozilla.javascript.WrappedException: Wrapped java.lang.ClassNotFoundException: com.mysql.jdbc.Driver

(/report/method[@name="initialize"]#6)
at org.mozilla.javascript.Context.throwAsScriptRuntimeEx(Context.java:1773)
at org.mozilla.javascript.MemberBox.invoke(MemberBox.java:183)
at org.mozilla.javascript.NativeJavaMethod.call(NativeJavaMethod.java:247)
at org.mozilla.javascript.optimizer.OptRuntime.call1(OptRuntime.java:66)
at org.mozilla.javascript.gen.c9._c0(/report/method[@name="initialize"]:6)
at org.mozilla.javascript.gen.c9.call(/report/method[@name="initialize"])
at org.mozilla.javascript.ContextFactory.doTopCall(ContextFactory.java:398)
at org.mozilla.javascript.ScriptRuntime.doTopCall(ScriptRuntime.java:3065)
at org.mozilla.javascript.gen.c9.call(/report/method[@name="initialize"])
at org.mozilla.javascript.gen.c9.exec(/report/method[@name="initialize"])
at org.eclipse.birt.report.engine.javascript.JavascriptEngine.evaluate(JavascriptEngine.java:282)
... 59 more
Caused by: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver
at org.eclipse.osgi.internal.loader.BundleLoader.findClassInternal(BundleLoader.java:506)
at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:422)
at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:410)
at org.eclipse.osgi.internal.baseadaptor.DefaultClassLoader.loadClass(DefaultClassLoader.java:107)
at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:169)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.mozilla.javascript.MemberBox.invoke(MemberBox.java:161)
... 68 more

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Comments

CBR

java.lang.Class.forName doesn't work in that case because of the classloader hierarchy. You can have a search on the forum because we already had this question a year ago.
There is some workaround so that you can get the Class.forName working in that context, but it's not worth it because even then you are not able to work with the database correctly (i will have a look if i can find the corresponding thread later)
the simplest thing would be to use a Java Event Handler and to readd the JDBC driver jar's to the event handlers classpath once again. Inside the java event handler you can easily work with the database like in good old Java.

CBR

by the way:
It would be interesting to know if this works with BIRT 3.7.1 (things look different because it is not OSGI based any more)

CBR

there it is: http://www.birt-exchange.org/org/forum/index.php/topic/17800-scripted-data-source-using-sql-entirely-in-rhino/

millvall

Hi cbrell,

Thanks for your replies.
Same result on BIRT 3.7. Or maybe there's a setting I need to set to alter the class loader? (If you know?)
Or maybe a way to extend the Rhino engine to recognize more JAR files.
Closest I got was:

//

var t = new com.mysql.jdbc.Driver();
java.sql.DriverManager.registerDriver(t);
var conn = java.sql.DriverManager.getConnection( "jdbc:mysql://localhost:3306/auditDatabase", null, null );
//

I get...
Wrapped java.sql.SQLException: No suitable driver found for jdbc:mysql://localhost:3306/auditDatabase

Which is slightly better than ClassNotFound.
I check the value of t:
t = class com.mysql.jdbc.Driver // Good.
t.jdbcCompliant() gives false // Odd?

It is frustrating when various readme.txt files tell you to copy your JDBC driver to this directory, then
it doesn't work. Maybe an engineer at Actu could do some work on this area, and save users lots of time.

=== readme.txt telling developer to put driver/JARS here... ======
C:\eclipse37\eclipse\plugins\org.eclipse.birt.report.data.oda.jdbc_3.7.1.v20110905\drivers
Place JDBC drivers' JAR files in this directory to make them available to BIRT.
//

C:\eclipse37\eclipse\plugins\org.eclipse.birt.report.viewer_3.7.1.v20110905\birt
The default directory to place BIRT script lib files.

Thanks again.
Milt.

- eom -

CBR

Hi,

it is because of the way bundle seperation works in OSGI.
The BIRT designer is always based on OSGI. The birt runtime is non OSGI based starting with 3.7
Your code would not work in any designer version.
The directory that is mentioned in the documentation is accessible by the JDBC datasource bundle only. The bundle that executes your rhino code is a different one, so it has a different classloader.
You could try adding the jdbc driver to the classpath of that bundle.

For the runtime you need to do the same or use 3.7 and add the jdbc driver to the classpath of your runtime application. I ll try on my own to see if it works.

There are no properties for OSGI to alter classloader

millvall

Hi cbrell,

I ended up writing a Java helper class to do the class loading and execute the query to INSERT some rows.
I call the methods from JavaScript in afterFactory. It works fine. Code below.
If you get you model working, plz post. Thanks
Milt.

package mvJDBCMySQL;
import java.sql.*;

public class mvJDBCMySQLHelper2 {

private Connection conn = null;
private Statement s = null;

// Full list of MySQL error codes are at:
// http://dev.mysql.com/doc/refman/5.5/en/error-messages-server.html
// To get code: e.getErrorCode();
//
// To get driver:
// String driverName = connection.getMetaData().getDriverName();
//

// Class Method
public static int mvJDBCGetVersion() { return 104; }

//

public java.sql.Connection mvJDBCGetConnection(String driverName,
String url,
String user,
String password)
{ // Start method

try
{ java.lang.Class.forName(driverName); }
catch (Exception e ) { System.out.println("Ex: Class.forname");
}
//

try
{ conn = DriverManager.getConnection(url, user, password); }
catch(SQLException se) { System.out.println("Ex: getConnection");
return null;
}
//

// If here..OK. Return the connection.
return conn;

} // End method

public int mvJDBCExecuteInsert(String query)
{ // Start method
// Use for INSERT rows to get back row count (RC)

int i = 0;
try
{
s = this.conn.createStatement();
s.setQueryTimeout(5); // 5 second query timeout

System.out.println("Statement type = " + s.getClass().toString() );
// Execute the statement, get row count back
i = s.executeUpdate (query);
//System.out.println("Update OK Rows inserted: " + i);
}
catch(SQLException se) { System.out.println("Ex: Insert fail"); }

return i;
}
//

public void mvJDBCClose()
{

// Close Statement and Connection
//

try
{
this.s.close();
//System.out.println("Statement close OK" );
}
catch(SQLException se) { System.out.println("Ex: Statement close fail"); }
//

try
{
// Execute the INSERT statement
this.conn.close();
//System.out.println("Conn close OK" );
}
catch(SQLException se) { System.out.println("Ex: Connection close fail"); }

} // End method
} // End Class

mehdiesteghamat

<p>hi Millvall,</p>
<p> </p>
<p>I would like to connect to an Oracle database on initialize to populate some parameters into my report initially. </p>
<p> </p>
<p>The BIRT version is 2.3. Please let me know how I can find folders which I need to put the Oracle jar file in.</p>
<p> </p>
<p>Ideally, I would like the code to look like below.</p>
<p> </p>
<p> </p>
<div> Packages.java.sql.DriverManager.registerDriver(new Packages.oracle.jdbc.driver.OracleDriver());</div>
<div> var con = Packages.java.sql.DriverManager.getConnection(DBURL, DBUSER, DBPASS);</div>
<div> var statement = con.createStatement();</div>
<div> var rs = statement.executeQuery("SELECT SYSDATE FROM DUAL");</div>
<div> if (rs.next()) {</div>
<div> var currentDate = rs.getDate(1); // get first column returned</div>
<div> Packages.System.out.println("Current Date from Oracle is : "+currentDate);</div>
<div> }</div>
<div> rs.close();</div>
<div> statement.close();</div>
<div> con.close();</div>
<div> </div>
<p> </p>
<p> </p>
<p>Please let me know,</p>
<p>Thank you,</p>

JFreeman

<p>You should be able to place the driver jar in "./eclipse/plugins" to make it available for importing.</p>
<p> </p>
<p>Alternatively, you can place the jar into your eclipse project directory and then add it to the report through the Resources tab in the Property Editor for the report.</p>