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Fetch Type - Lazy vs. Eager Loading in EJB 3.0:

}

Advantages of EJB 3.0:

The below are the some of the advantages of using EJB 3.0

1. More work is done by container,less by developer
2. Everything is a POJO(Plain old java object)
3. Simplify programming model
4. Hibernate like ORM(Object Relational Mapping)
5. Dependency injection
6. Annotations(Requires Java 5)
7. Bean specifies what it needs through metadata
8. No longer written to unneeded container interfaces
9. Deployment descriptor no longer required

The below java code will help us to Download/Upload files from/To FTP server.

import java.io.*;
import java.net.*;

public class FTPClient {
    public final String host;
    public final String user;
    protected final String password;
    protected URLConnection ftpurl;

    public FTPClient(String host, String user, String password) {
        this.host = host;
        this.user = user;
        this.password = password;
        this.ftpurl = null;
    }

    private URL createURL(String destfile) throws MalformedURLException {
        if (user == null)
            return new URL("ftp://" + host + "/" + destfile + ";type=i");
        else
            return new URL("ftp://" + user + ":" + password + "@" + host +"/" + destfile + ";type=i");
    }

    protected InputStream openDownloadStream(String destfile) throws Exception {
        URL url = createURL(destfile);
        ftpurl = url.openConnection();
        InputStream is = ftpurl.getInputStream();
        return is;
    }

    protected OutputStream openUploadStream(String targetfile) throws Exception {
        URL url = createURL(targetfile);
        ftpurl = url.openConnection();
        OutputStream os = ftpurl.getOutputStream();
        return os;
    }

    protected void close() {
        ftpurl = null;
    }

    public void Upload(String sourcefile, String destfile) {
        try {
            OutputStream os = openUploadStream(destfile);
            FileInputStream is = new FileInputStream(sourcefile);
            byte[] buf = new byte[33554432];
            int c;
            while (true) {
                c = is.read(buf);
                if (c <= 0)
                    break;
                os.write(buf, 0, c);
            }
            os.close();
            is.close();
            close();
        } catch (Exception e) {
            System.err.println(e.getMessage());
            e.printStackTrace();
        }
    }

    public void Download(String sourcefile, String destfile) {
        try {
            InputStream is = openDownloadStream(destfile);
            FileOutputStream os = new FileOutputStream(sourcefile);
            byte[] buf = new byte[41943040];//Buffer size set to 40 MB ,change based on the file size
            int c;
            while (true) {
                c = is.read(buf);
                if (c <= 0)
                    break;
                os.write(buf, 0, c);
            }
            is.close();
            os.close();
            close();
        } catch (Exception e) {
            System.err.println(e.getMessage());
            e.printStackTrace();
        }
    }
}

Setting the Composite Instance Name (Title) in Oracle Mediator - Oracle SOA Suite:

 
 
 

 Recovering the Oracle BPEL instances from the Recovery Queue – Oracle SOA:

1. There are not enough threads or memory to process the message.
2. The server shuts down or crash before it finishes processing the BPEL message
3. The engine could not finish processing the message before reaching the time-out as dictated by the transaction-timeout configuration

Recovering the BPEL instances:

Oracle SOA Suite 11g:

1. Login  to EM console
2. Right click on soa-infra  ,Click on Service Engine - BPEL
3. Click on Recovery tab
4. Change the Type accordingly(Invoke,Activity,Callback) and the Message state to “Undelivered”  and click on search
5. All the recoverable messages that match the criteria will be displayed.
6. Select the required messages and click on Recovery button.

 

 

The below Java code will help us to decrypt the weblogic server password

import weblogic.security.internal.SerializedSystemIni;
    import weblogic.security.internal.encryption.ClearOrEncryptedService;
    import weblogic.security.internal.encryption.EncryptionService;
   
    public class Decrypt {
        public static void main(String[] args) {
            String string = args[0];
            EncryptionService encryptionService = SerializedSystemIni.getEncryptionService();
            ClearOrEncryptedService clearOrEncryptedService = new ClearOrEncryptedService(encryptionService);
            System.out.println("Clear text password: " + clearOrEncryptedService.decrypt(string));
        }
    }

1. Log in to Oracle WebLogic Server Administration Console.
2. In the Domain Structure, select Services > JTA
3. Increase the JTA transaction timeout value to some higher value like 3600

1. Log in to Oracle WebLogic Server Administration Console.
2. In the Domain Structure, click Deployments.
3. Expand soa-infra > EJBs.
4. Update the following EJBs transaction Timeout value to some higher value like 1200:

5. Click Save.
6. Restart Oracle WebLogic Server.

Java code to Marshal/Unmarshal XML using JAXB:

Unmarshalling:

JAXBContext jc =JAXBContext.newInstance("com.java.test");//add multiple packages seperated by ":" eg.com.java.test1:com.java.test2
Unmarshaller u = jc.createUnmarshaller();
JAXBElement obj =(JAXBElement)u.unmarshal(new File(inputXMLPath)); // ok

Marshalling

Marshaller marshaller = jc.createMarshaller();
marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT,Boolean.TRUE);
String outXML = "Response.xml";
marshaller.marshal(obj,new FileOutputStream(outXML));