Help Guide For Software Engineer

Embed Image in Email Using java

2012-01-30T19:28:00.000-08:00

Following code snippet can be used to send email with image in the HTML body.

Note :- HTML body must be contain image tag as follows.

<img height="55" src="cid:image-id" width="65" />

Properties properties = new Properties();
properties.put("mail.smtp.host", "smtp host ip ");
Session session = Session.getDefaultInstance(properties, null);

MimeMessage message = new MimeMessage(session);
message.setFrom(new InternetAddress(from));
message.setRecipient(Message.RecipientType.TO, new InternetAddress(to));
message.setSubject(subject);
message.setSentDate(new Date());

MimeBodyPart messagePart = new MimeBodyPart();
messagePart.setDataHandler(new DataHandler(new ByteArrayDataSource(body, "text/html")));
Multipart multipart = new MimeMultipart("related");
multipart.addBodyPart(messagePart);
multipart.addBodyPart(attachmentPart);

MimeBodyPart imagePart = new MimeBodyPart();
DataSource fds = new FileDataSource("image path ");
imagePart.setDataHandler(new DataHandler(fds));
imagePart.setFileName("logo.jpg");
imagePart.setHeader("Content-ID", "<image-id>

");

imagePart.setDisposition(MimeBodyPart.INLINE);
multipart.addBodyPart(imagePart);

message.setContent(multipart);
Transport.send(message);

dwr mapping filter

2012-01-24T22:10:00.000-08:00

<filter>
<filter-name>dwrFilter</filter-name>
<filter-class>org.directwebremoting.servlet.DwrWebContextFilter</filter-class>
</filter>

<filter-mapping>
<filter-name>dwrFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>

This filter can be used to redirect request for DWR servlet.

Truncate nohup.out file in linux

2011-11-07T01:42:00.000-08:00

While sending your program output to file called nohup.out, you can't simply delete the file. Since, it is handled in server memory. In that case, you have to empty file using following command.

If you delete nohup.out, while running your program, it will leads to server memory growing and become server unstable.

change the working directory to location where your nohup.out file reside. Then execute the following command to empty the file.

cat /dev/null >nohup.out

NOTE :- nohup.out is in linux for gathering program output data. If you run application as following output will redirect to the nohup.

nohup java -jar testApp.jar

Find multicast groups

2011-10-25T20:28:00.000-07:00

In windows, use following commands to find multicast groups.

Open command prompt and run the following command in terminal.

netsh interface ip show joins

Find contents in files

2011-09-16T04:08:00.000-07:00

Suppose, there are many files that contains "CONTENT" you want to search, use the following command in the Linux terminal.

grep "CONTENT" *.*

Create Scheduler in Java

2011-09-09T03:21:00.000-07:00

Some applications need to run on a scheduled time. This java application runs on every Sunday midnight.

import java.util.Calendar;
import java.util.Date;
import java.util.Timer;
import java.util.TimerTask;

public class ScheduleTest extends TimerTask {

public void run() {
System.out.println("Schedule working ");
//TODO
}
}

class Application {

public static void main(String[] args) {

Timer timer = new Timer();
Calendar date = Calendar.getInstance();

date.set(
Calendar.DAY_OF_WEEK,
Calendar.SUNDAY
);

date.set(Calendar.HOUR, 0);
date.set(Calendar.MINUTE, 0);
date.set(Calendar.SECOND, 0);
date.set(Calendar.MILLISECOND, 0);

// Schedule to run every Sunday in midnight

timer.schedule(
new ScheduleTest (),
date.getTime(),
1000 * 60 * 60 * 24 * 7
);
}
}

Conversion between signed & unsigned byte

2011-08-30T01:33:00.000-07:00

Convert byte value from signed to unsigned

Use '&' operation with 0xFF as follows.
Suppose signed byte value is byt (-120,64,....).

byt & 0xFF

Above will convert signed to unsigned and return unsigned value.

Convert byte value from unsigned to signed

ByteBuffer byteBuff = ByteBuffer.allocate(4);
byteBuff.putInt(intValue);
by[i] = byteBuff.get(3);

Above code convert unsigned values to sign byte values.

How to get System information in windows

2011-08-21T23:54:00.000-07:00

Open command prompt
Type "systeminfo" command
Run the command

This will get a few seconds to load information.

View Linux version using command

2011-08-11T02:41:00.000-07:00

Use following command to get linux version.

uname -a

Mysql set auto increment start value

2011-08-08T03:56:00.000-07:00

In default, auto increment values are started in 0(zero). Suppose you, want to start value auto increment with 1234, use the following command after table creation.

ALTER TABLE TableName AUTO_INCREMENT=1234

Get last bash command in shell

2011-07-20T04:54:00.000-07:00

Suppose you want to get previously used command without using up / down arrows,

Simply type !(command start char).

Example :-

If you want to get "ps -eaf|grep java", simply type !p in the bash shell.

NOTE :- This will return last executed command.

RSA java encrypt, decrypt

2011-07-20T04:48:00.000-07:00

Following code can be used to encrypt, decrypt string using RSA encryption.

NOTE :- Apache Commons Codec used for encode string to base64.

import java.math.BigInteger;
import java.security.KeyFactory;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.spec.RSAPrivateKeySpec;
import java.security.spec.RSAPublicKeySpec;

import javax.crypto.Cipher;
import org.apache.commons.codec.binary.Base64;

public class MainClass {

public static void main(String[] args) throws Exception {
byte[] expBytes = Base64.decodeBase64("AQAB");
byte[] modBytes = Base64.decodeBase64("nzLiZDSiu484r5NcBQN3rNP3x5aqY3Eq6CkQDwuilTzd5ZNdTcTxw7C1JQ9ih27Vq4RU9NYgi9oOUTVQ2gkqP1OJA9aawjCRwMJ7PRyKlBEpsdE/wFtu9/1ciGRtWSyACr2jTASZPQa+aHQh2qziacWd+iVmGIq0+l11nGG/GYU=");
byte[] dBytes = Base64.decodeBase64("nyF45NssUzkdW3t7/tLxfENBKTN0TARh9ECfebqSoIR/9awxFrynQYnP+CSBw4jJcjHLzhR/4etsZkZZ9Cg3HhPA5pjVcI5kJct4kLjWM+ejZliZoV/KvpJN261VKKLTJMX64UeMiLAlb7mUNoNqKztgflxz5Dbad5hemvgwg50=");

BigInteger modules = new BigInteger(1, modBytes);
BigInteger exponent = new BigInteger(1, expBytes);
BigInteger d = new BigInteger(1, dBytes);

KeyFactory factory = KeyFactory.getInstance("RSA");
Cipher cipher = Cipher.getInstance("RSA");
String input = "test";

RSAPublicKeySpec pubSpec = new RSAPublicKeySpec(modules, exponent);
PublicKey pubKey = factory.generatePublic(pubSpec);
cipher.init(Cipher.ENCRYPT_MODE, pubKey);
byte[] encrypted = cipher.doFinal(input.getBytes("UTF-8"));
System.out.println(encrypted);
System.out.println("encrypted: " + new String(encrypted));

RSAPrivateKeySpec privSpec = new RSAPrivateKeySpec(modules, d);
PrivateKey privKey = factory.generatePrivate(privSpec);
cipher.init(Cipher.DECRYPT_MODE, privKey);
byte[] decrypted = cipher.doFinal(encrypted);
System.out.println("decrypted: " + new String(decrypted));
}
}

vi editor command

2011-05-26T00:50:00.000-07:00

When you use Linux vi editor above commands will help you.

Java script to get list box text

2011-03-29T21:02:00.000-07:00

When you want to get list box selected text from your application using java script use the following js code.

var w = document.getElementById('picklistid').selectedIndex;

var selected_text = document.getElementById('picklistid').options[w].text;

selected_text variable will be returned the combo box selected text.

Mysql Date

2011-03-09T18:31:00.000-08:00

Some useful SQL commands to get dates in Mysql server.

select curdate()	3/10/2011
select curdate()-1	20110309
select curdate() - INTERVAL 1 DAY	3/9/2011

Mysql enable logging

2011-02-27T23:02:00.000-08:00

mysql > tee output.log

Mysql has default built in function to logging transactions. In Mysql client, type above command. It will enabled logging in transaction. "output.log" file is created in Mysql bin directory.

Find process id in linux

2011-02-06T20:50:00.000-08:00

Use the below command to find the process id of your application. Here app name is "TestApp.jar".

ps -ef | grep TestApp

Run .jar file with log

2011-02-06T19:50:00.000-08:00

Use the following command to run jar file for logging errors.

nohup java -jar -Xms1024m -Xmx2048m Test.jar &

Above command will run the "Test.jar" file in background and produce error file called "nohup" in same directory. ( All system out prints will be redirected into this file). So, developers can catch errors using the "nohup".

Mysql Current date & time

2011-02-02T20:36:00.000-08:00

Use the Mysql server curdate() and curtime() functions to get current date & time values from the system.
Below SQL demos, the usage of the functions.

insert into test(cur_date,cur_time) values(curdate(),curtime());

Mysql data unload

2011-01-06T21:58:00.000-08:00

Use the following SQL to unload data from Mysql server without executing command. This method is good for very large set of data.

select * from table into outfile "file.txt"

Note :- file.txt will be created at"MySQL/data/database" directory.

Mysql Triggers Example

2010-12-16T03:36:00.000-08:00

Mysql triggers are like schedulers run on table changes. When INSERT, DELETE, UPDATE command executions, these triggers are executed automatically.

Below is a sample of SQL commands to create and test Triggers when insert happens to "test1" table.

Create below four tables and insert values into "test3" & "test4" tables.

Trigger

This Trigger is executed when insert happens into "test1" table. It gets "test1.a1" value and insert it into "test2" table. And, delete it from "test3" table. Update "test4" b4 value.

Create Tables

CREATE TABLE test1(a1 INT);
CREATE TABLE test2(a2 INT);
CREATE TABLE test3(a3 INT NOT NULL AUTO_INCREMENT PRIMARY KEY);
CREATE TABLE test4(
a4 INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
b4 INT DEFAULT 0
);

Create Trigger 

delimiter |

CREATE TRIGGER testref BEFORE INSERT ON test1
FOR EACH ROW BEGIN
INSERT INTO test2 SET a2 = NEW.a1;
DELETE FROM test3 WHERE a3 = NEW.a1;
UPDATE test4 SET b4 = b4 + 1 WHERE a4 = NEW.a1;
END;
|

Insertions

delimiter ;

INSERT INTO test3 (a3) VALUES
(NULL), (NULL), (NULL), (NULL), (NULL),
(NULL), (NULL), (NULL), (NULL), (NULL);

INSERT INTO test4 (a4) VALUES
(0), (0), (0), (0), (0), (0), (0), (0), (0), (0);

Executes following SQL to run the Trigger.

INSERT INTO test1 VALUES (1), (3), (1), (7), (1), (8), (4), (4);

IReport dynamic table sql

2010-11-15T21:42:00.000-08:00

In IReport tool, you can dynamically generate SQL by changing table name.

1) Create parameter for table name. Ex :- $P{tableName}
2) Change IReport SQL as following.

      SELECT * FROM $P!{tableName}

limit Resultset size in informix

2010-11-10T20:48:00.000-08:00

Use the following SQL to limit the size of the result set in informix.

SELECT FIRST 1 * FROM orders

Get map for latitude & longitude using Google Maps API

2010-10-26T20:10:00.000-07:00

Google provides a FREE Java Script map API for longitude & latitude. Simple demonstration is given below. Position marker, mouse wheel zooming, Map view/Satelite view/Hybrid view controls are enabled in the example.

NOTE :- Map searching is commented.

<html>
<head>
<script type="text/javascript"
src="http://www.google.com/jsapi?key=ABCDEFG"></script>
<script type="text/javascript">
google.load("maps", "2");
//  google.load("search", "1");

// Call this function when the page has been loaded

function initialize() {
var map = new google.maps.Map2(document.getElementById("map"));
map.setCenter(new google.maps.LatLng(7, 80), 13);
map.enableRotation();
map.addControl(new GOverviewMapControl());
map.enableDoubleClickZoom();
map.enableScrollWheelZoom();
map.addControl(new GMapTypeControl());

map.addControl(new GSmallMapControl());

var marker = new GMarker(new GLatLng(7, 80));
map.addOverlay(marker);
map.setMapType(G_SATELLITE_MAP);

//        var searchControl = new google.search.SearchControl();
//        searchControl.addSearcher(new google.search.WebSearch());
//        searchControl.addSearcher(new google.search.NewsSearch());
//        searchControl.draw(document.getElementById("searchcontrol"));
}

google.setOnLoadCallback(initialize);
</script>

</head>
<body>
<div id="map" style="width: 500px; height: 500px"></div>
<!-- <div id="searchcontrol"></div> -->
</body>

</html>

Reference :- http://code.google.com/apis/ajax/documentation/ 

Shell Script to load data from a TableA to TableB in mysql

2010-10-12T20:57:00.000-07:00

Suppose you have to select custom fields in TableA and insert those fields into TableB in mysql, then the following shell script command would be appropriate.

mysql -u user -p -D database -e 'insert into TableB select id, addr from TableA;'

Insert above code in a file and save it as ".sh" file extension. Then run it as "./Test.sh".

NOTE :- Test.sh must be stored in the server that mysql db server is running.

Remove non empty directory in linux

2010-10-07T04:38:00.000-07:00

Use the below command to remove non empty directory in Linux without prompting for verification "yes" or "no".

rm -rf directory

This will remove all the contents in the directory without asking further verifications for files deletion.

File download using Struts

2010-08-30T23:26:00.000-07:00

In some developments, you have to prompt "OPEN/SAVE" dialog for file viewing.
Here is a sample code for file download with the support of the "DownloadAction".

import java.io.IOException;
import java.io.InputStream;
import java.io.ByteArrayInputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionMapping;
import org.apache.struts.actions.DownloadAction;


public class ExampleByteArrayDownload extends DownloadAction {

    protected StreamInfo getStreamInfo(ActionMapping mapping, 
                                       ActionForm form,
                                       HttpServletRequest request, 
                                       HttpServletResponse response)
            throws Exception {
   
        String fileName = httpServletRequest.getParameter("fileName");

        String fileExtension =
            fileName.substring(fileName.lastIndexOf("."), fileName.length());

        httpServletResponse.setHeader("Content-Disposition",
                                      "attachment;filename=\"" + fileName +
                                      "\"");
        
        // Download a "pdf" file
        String contentType = "application/pdf";
        byte[] myPdfBytes  = null;              // Get the bytes from somewhere

        return new ByteArrayStreamInfo(contentType, myPdfBytes);
        
    }

    protected class ByteArrayStreamInfo implements StreamInfo {
        
        protected String contentType;
        protected byte[] bytes;
        
        public ByteArrayStreamInfo(String contentType, byte[] bytes) {
            this.contentType = contentType;
            this.bytes = bytes;
        }
        
        public String getContentType() {
            return contentType;
        }

        public InputStream getInputStream() throws IOException {
            return new ByteArrayInputStream(bytes);
        }
    }
}

Reference
http://wiki.apache.org/struts/StrutsFileDownload

Replace String pattern in "Vi"

2010-07-28T21:53:00.000-07:00

1) Open the TEXT file using "vi" editor in linux.
2) Press ESC
3) Following command will replace "tab" character by "|".

    :%s/     /|/g

4) Save & quit file using following command.

    :wq!

Java property file usage

2010-07-19T23:23:00.000-07:00

Use the below code to read the java property file and retrieve the property value.

      Properties properties = new Properties();
        FileInputStream in;
        try {
            in = new FileInputStream("app.properties");
            properties.load(in);
            in.close();
        } catch (Exception e) {
            System.out.println(e.getMessage());
        }
        return properties.getProperty("appcode");

Sample "app.properties" file is shown below.

appcode=50
email=admin@yahoo.com

From date < To date validate using js

2010-07-06T23:49:00.000-07:00

Use the below js code to validate date "From date < To date"

         var frmDate = document.getElementById("frmDate").value;
         var toDate = document.getElementById("toDate").value;

         if (frmDate < toDate) {
             alert("Invalid Date Range!\nStart Date cannot be after End Date!")
             return false;
         }

Solution to dwr session error

2010-06-23T05:42:00.000-07:00

Edit your web.xml file and and the following code.

<init-param>
<param-name>crossDomainSessionSecurity</param-name>
<param-value>false</param-value>
</init-param>

Move large number of files in solaris using "awk"

2010-05-09T20:30:00.000-07:00

Change directory where your files are located.
Use the following "awk" script to move files from one location to another.

for k in `ls | awk '{print $1}'`;
do
mv $k destination;
done

Use java 64 bit version

2010-05-03T00:36:00.000-07:00

You have to use 64bit version of java when your memory allocation is larger than 4Gb.

Use -d64 parameter when running the application.

java -d64 -jar -Xms1024m -Xmx4096m Test.jar

Type Cast in Java Script

2010-05-02T21:35:00.000-07:00

In js, variables are created as var type. That means, js engine can cast it to the original type by itself.

parseInt(12) will be converted 12 to an Integer value.

           Example                   Result
parseInt("12")                          12
parseInt("12.657")                    12
parseInt("12aaaa")                   12
parseInt("aaaa")                NaN (means "Not a Number")

Encrypt, Decrypt password in Mysql

2010-04-23T02:48:00.000-07:00

Inserting password encrypted to database using the following sql.

INSERT INTO PASSWORD(pass) VALUES(DES_ENCRYPT('user password')); 

This SQL will encrypt the user inserted password to a encrypted text. In table level, password is unreadable.

Instead of DES_ENCRYPT() method you can come up with your own function.

Selecting password from database to a string.

SELECT DES_DECRYPT(pass) FROM PASSWORD ;

This SQL will return user password as user inserted.

weblogic.xml to use on memory session replication

2010-03-29T20:48:00.000-07:00

<?xml version="1.0" encoding="UTF-8" ?>

<weblogic-web-app xmlns="http://www.bea.com/ns/weblogic/90"

xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">

<session-descriptor>

<timeout-secs>300</timeout-secs>

<invalidation-interval-secs>60</invalidation-interval-secs>

<persistent-store-type>jdbc</persistent-store-type>

<persistent-store-pool>SessionDS</persistent-store-pool>

<persistent-store-table>WL_SERVLET_SESSIONS</persistent-store-table>

</session-descriptor>

</weblogic-web-app>

Use the above code for weblogic.xml. Your weblogic cluster MUST be configured to use jdbc persistence store to capture web-browsers and nodes sessions. WL_SERVLET_SESSIONS is the table for session store.

Add this weblogic.xml file to your WEB-INF directory and deploy your application to the weblogic cluster. When a cluster node down, it will replicate all the JSP sessions associates with the clients.

Add your own jars to weblogic application

2010-03-14T21:16:00.000-07:00

Sometimes weblogic server uses its server lib .jars. If you want your application to use your own versions of .jar files, add following code to your weblogic.xml file located in WEB-INF directory.

<container-descriptor>
<prefer-web-inf-classes>true</prefer-web-inf-classes>
</container-descriptor>

This will use libraries in your application.

Java Application Memory utilization

2010-02-25T03:15:00.000-08:00

java -jar -Xms64m -Xmx128m Test.jar

When running your java application, use above arguments. This will allocate 64MB minimum for your application and 128MB maximum. If 128MB exceeds, java will call the garbage collector.

Writing console output to a file in java

2010-02-10T02:00:00.000-08:00

Use this code to write your console outputs to a file using java.

import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.PrintStream;

public class RedirectIO {

public static void main(String[] args) {

PrintStream orgStream = null;
PrintStream fileStream = null;

try {

// Saving the orginal stream
orgStream = System.out;
fileStream = new PrintStream(new FileOutputStream("d:/123.txt",true));

// Redirecting console output to file
System.setOut(fileStream);

// Redirecting runtime exceptions to file
System.setErr(fileStream);

throw new Exception("Test Exception");

}catch (FileNotFoundException fnfEx){
System.out.println("Error in IO Redirection");
fnfEx.printStackTrace();
}catch (Exception ex){
ex.printStackTrace();
//Gets printed in the file
System.out.println("Redirecting output & exceptions to file");
}finally{
//Restoring back to console
System.setOut(orgStream);
//Gets printed in the console
System.out.println("Redirecting file output back to console");
}
}
}

Stack Trace of the Exception to a String

2010-02-06T10:48:00.000-08:00

Use this code inside your catch block. This will return a string.

}catch(Exception e){

StringWriter sWriter = new StringWriter();
e.printStackTrace(new PrintWriter(sWriter));
System.out.println(sWriter.getBuffer().toString()) ;

}

Task Manager in Solaris Console

2010-02-02T19:36:00.000-08:00

In console type "prstat".

This will show a program looks like windows Task manager.

Embed fonts for pdf usng itext

2010-01-17T20:32:00.000-08:00

Usually, "consola" font family is not used for pdfs, because it is not available in all systems. Using following code sample, you can embed your interested fonts for pdfs.

Registering regular True type "consola" font.

FontFactory.register("D:\\consola.ttf", "Manning");
FontFactory.getFont("Manning", BaseFont.CP1252, BaseFont.EMBEDDED);

Registering bold True type "consola" font.
FontFactory.register("D:\\consolab.ttf","Manning");
FontFactory.getFont("Manning", BaseFont.CP1252, BaseFont.EMBEDDED);

Graphical + Attachment java Email Client

2009-12-14T02:28:00.000-08:00

import java.util.Properties;
import javax.activation.DataHandler;
import javax.activation.FileDataSource;
import javax.mail.Message;
import javax.mail.Multipart;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeBodyPart;
import javax.mail.internet.MimeMessage;
import javax.mail.internet.MimeMultipart;

public class EmailClient {

private static final String SMTP_HOST_NAME = "smtp.gmail.com";
private static final String SMTP_AUTH_USER = xxx@gmail.com;
private static final String SMTP_AUTH_PWD = "xxx";

public static void main(String[] args) throws Exception {

new SimpleMailWithAttachment().test();

}
public void test() throws Exception {
Properties props = new Properties();
props.put("mail.transport.protocol", "smtp");
props.put("mail.host", SMTP_HOST_NAME);

Session mailSession = Session.getDefaultInstance(props, null);
mailSession.setDebug(true);
Transport transport = mailSession.getTransport();
MimeMessage message = new MimeMessage(mailSession);
message.setSubject("Testing javamail with attachment");
MimeBodyPart textPart = new MimeBodyPart();
textPart.setContent("<h1>Check attachment</h1>", "text/html");
MimeBodyPart attachFilePart = new MimeBodyPart();

FileDataSource fds =
new FileDataSource("d:\\TwainExample.java");

attachFilePart.setDataHandler(new DataHandler(fds));
attachFilePart.setFileName(fds.getName());
Multipart mp = new MimeMultipart();
mp.addBodyPart(textPart);
mp.addBodyPart(attachFilePart);
message.setContent(mp);
message.addRecipient(Message.RecipientType.TO,
new InternetAddress("xxx@yahoo.com"));
transport.connect(SMTP_HOST_NAME, SMTP_AUTH_USER,
SMTP_AUTH_PWD);
transport.sendMessage(message,
message.getRecipients(Message.RecipientType.TO));
transport.close();
}
}

Disable enter key using java script

2009-12-11T00:21:00.000-08:00

Use the below code to disable enter key. You can also used this to disable un wanted keys,too. Just add more combination of keys after "evt.keyCode == 13".
<html>
<head>
<script language=javascript type=text/javascript>

</script>
</head>
<body>
<textarea rows="5"></textarea>
</body>
</html>

How to write & read cookie in java?

2009-12-10T02:06:00.000-08:00

In this jsp page you can pass the value you want to set as your cookie.

<%@ page language="java" %>
<html>
<head>
<title>Cookie Input Form</title>
</head>
<body>
<form method="post" action="setcookie.jsp">
<p><b>Enter Your Name: </b><input type="text" name="username"><br>
<input type="submit" value="Submit">
</form>
</body>

This page captures the cookie input value and set cookie in client hard disk.

<%@ page language="java" import="java.util.*"%>
<%
String username=request.getParameter("username");
if(username==null) username="";

Date now = new Date();
String timestamp = now.toString();
Cookie cookie = new Cookie("username",username);
cookie.setMaxAge(365 * 24 * 60 * 60);
response.addCookie(cookie);

%>
<html>
<head>
<title>Cookie Saved</title>
</head>
<body>
<p><a href="showcookievalue.jsp">Next Page to view the cookie value</a><p>
</body>

This is a page you can to use to see the cookie value later time.
<%@ page language="java" %>
<%
String cookieName = "username";
Cookie cookies [] = request.getCookies ();
Cookie myCookie = null;
if (cookies != null)
{
for (int i = 0; i < cookies.length; i++)
{
if (cookies [i].getName().equals (cookieName))
{
myCookie = cookies[i];
break;
}
}
}
%>
<html>
<head>
<title>Show Saved Cookie</title>
</head>
<body>
<%
if (myCookie == null) {
%>
No Cookie found with the name <%=cookieName%>
<%
} else {
%>
<p>Welcome: <%=myCookie.getValue()%>.
<%
}
%>
</body>

Use keytool to generate keys in java

2009-12-02T18:34:00.000-08:00

keytool -genkey -alias weblogic -keyalg RSA -keystore server.keystore
keytool -selfcert -export -alias weblogic -storepass changeit -file server.cer -keystore server.keystore
keytool -genkey -alias client -keyalg RSA -keystore client.keystore
keytool -selfcert -export -alias client -storepass changeit -file client.cer -keystore client.keystore
keytool -import -v -trustcacerts -alias weblogic -file server.cer -keystore client.keystore -keypass changeit -storepass changeit
keytool -keystore \jre\lib\security\cacerts -storepass changeit -file client.cer -import -alias client -trustcacerts

Here, i have created server.cer and client.cer certificates. Password used is "changeit".

Use AXIS library to create web service and client

2009-11-26T19:03:00.000-08:00

Download AXIS binary and extract it to your hard disk.
Set up AXIS2_HOME and path environment veriables.

Create service using WSDL file

1) Open terminal.

2) Go to the directory you want to create service.

3) Run the below command.

wsdl2java -uri "test.wsdl" -ss -sd -d xmlbeans -o service

4) This will create a folder called "service" and created the service using the .wsdl file.

5) Go to the "service" folder and run "ant" command to build the .aar file.

6) Go to AXIS bin and run "axis2server.sh".

7) Put the created .aar file into AXIS repository\services folder.

8) It will auto deployed as a service.

9) You can access the service using "http://127.0.0.1:8080".

Create client using WSDL file

1) Open terminal.

2) Go to the directory you want to create client.

3) Run the below command.

wsdl2java -uri "test.wsdl" -d xmlbeans -o client

4) This will create a folder called "client" and created the client code using the .wsdl file.

DNS Mapping in windows

2009-11-18T00:01:00.000-08:00

Go to "C:\Windows\System32\drivers\etc".

Edit hosts file in etc folder. Add your ip addres and the mapping name.

Ex :-

192.168.4.7 name.domain.com

Now, you can access your ip address using DNS set above.

Ex :-

http://name.domain.com/App

Embed document in html

2009-10-29T04:49:00.000-07:00

embed a HTML document
<object data="data/test.html" type="text/html" width="300" height="200">
alt : <a href="data/test.html">test.html</a>
</object>
embed a pdf document
<object data="data/test.pdf" type="application/pdf" width="300" height="200">
alt : <a href="data/test.pdf">test.pdf</a>
</object>
embed a wav document
<object type="audio/x-wav" data="data/test.wav" width="200" height="20">
<param name="src" value="data/test.wav">
<param name="autoplay" value="false">
<param name="autoStart" value="0">
alt : <a href="data/test.wav">test.wav</a>
</object>

Clear clipboad using java script

2009-10-20T22:24:00.000-07:00

Call this java script method to clear your clipboard in IE6. Sorry, it doesn't work in Mozilla and other browsers.

function clsClipsBrd(){
clipboardData.clearData();
}

Create web service clients in java

2009-10-15T23:01:00.000-07:00

There is a tool to create web service clients called as "cxf". This is a free tool. You must have the wsdl file to create java clients.

Download URL :- http://cxf.apache.org/download.html
User guide :- http://ws.apache.org/axis/java/user-guide.html
Reference :- http://cxf.apache.org/docs/wsdl-to-java.html

Extract cxf zip file and change directory to /din in your terminal
use the follwing command to create java clients

wsdl2java HelloWorld.wsdl

Namespace error in JAX-WS

2009-10-15T22:55:00.000-07:00

Here is the error, i got when i am going to creat my web service client.

oracle.jdeveloper.webservices.model.WebServiceException: Error creating model from wsdl "http://127.0.0.1/Service.asmx?wsdl": undefined element declaration 's:schema'

I tried many ways to create my client using jdeveloper, but failed.

After that, i used axis web service for client implementation. It works fine in eclipse.

Create XML file in java

2009-10-15T22:39:00.000-07:00

This is a simple example of creating standard XML file in java.

DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder documentBuilder = documentBuilderFactory.newDocumentBuilder();
Document document = documentBuilder.newDocument();
Element rootElement = document.createElement("root");

This code segment creates a root element of the XML file.

Now, use this code to create child nodes to XML document.

Element em = document.createElement("element");
em.appendChild(document.createTextNode("data"));
rootElement.appendChild(em);

How to find informix cost factor

2009-09-17T20:47:00.000-07:00

Cost factor of a table is used to measure the performance of the sql executions. When your table cost factor is high, it will decrease the sql exection . That means it will get some times to generate resultsets of the sql.
Here is the way to measure informix cost factor.
Example :-
set explain on;
select * from table

Use set explain on; before your sql stetement in telnet client in dbaccess mode in informix.
Then exit dbaccess mode and type "ls -ltrh" in your home directory.
This will list all the files. Go to end. You will find a file called as "sqexplain.out".
Vi the file. Then press "shift+g" to end of the file to see your table cost factor details.

sql for monthly,yearly report

2009-09-11T04:30:00.000-07:00

select year(added_on),month(added_on),count(*) from table_name
group by 1,2
order by 2

This will produce a resultset for monthly yearly reports.

Ex :-

Year Month Records
------ ------ --------
2009 5 14416
2009 6 788
2009 7 15413
2009 8 16091

Mysql today in where clause

2009-09-02T03:40:00.000-07:00

select * from table where added_on=date(now());

To use this sql you must have used "date" datatype for your table column.
select * from table where added_at=now();

This works fine for "time" columns too .

Get radio button value in js

2009-08-31T20:31:00.000-07:00

Suppose your radio button grop is "radiogroup".
function getradioSelection() {
var group=document.getElementsByName("radiogroup");
var grp='';
for(var k=0;k<group.length;k++){
if(group[k].checked){
grp=group[k].value;
}
return grp;
}
This method will return the selected radio button value.

Insert data into mysql from text file

2009-08-25T21:28:00.000-07:00

Unload data into a text file.
Import data into a excel sheet. Then save the file again as .txt(Tab delimited) file.
Export file to your mysql server. vi the .txt file in linux. Then save the file using following command.

:%s/tab/|/g ---------->Then enter.
:wq! ------------->Save the file
LOAD DATA INFILE "table.txt" INTO TABLE table
FIELDS TERMINATED BY '|' LINES TERMINATED BY '\n' ----> Load data to mysql server

Unload/load data from informix

2009-08-25T21:09:00.000-07:00

unload to "table.txt" select * from table

This will unload data to your user login in database server. Suppose you logged as "test" user, it will unload data to folder "test".

load data from "table.txt" insert into table

Use this sql to load data from "table.txt" to a table.

2009-08-20T01:00:00.000-07:00

String qur="select a from table a";
Query q = em.createQuery(qur);
q.setFirstResult(0);
q.setMaxResults(10);

This will return the resultset limited to 10 in ejb.

How to log exceptions in dwr?

2009-08-07T01:12:00.000-07:00

Add the following jar files to your project library.

commons-logging-1.1.1.jar
commons-logging-adapters-1.1.1.jar
commons-logging-api-1.1.1.jar
commons-logging-tests.jar
commons-logging-1.1.1-javadoc.jar
commons-logging-1.1.1-sources.jar
dwr.jar

Remove time in java.sql.Date using sql

2009-08-04T04:46:00.000-07:00

to_char(disconnected_on,"%Y-%m-%d")

Here "disconnected_on" is the field in the table. If you use to_char() method it will remove time values and formate the date as "YYYY-MM-DD".

Ex :-
before use :- 2009-10-10 12:09
after usage :- 2009-10-10

Meta tag to refesh the page

2009-08-03T00:38:00.000-07:00

This is the meta tag that is used to refresh the page.

<META HTTP-EQUIV=Refresh CONTENT='100; URL=index.php'>
Here, CONTENT='100 means time interval for a refresh.
URL is the page/url must be refreshed.

One to Many Relational Mapping in ejb ( usage of jpa)

2009-07-31T02:41:00.000-07:00

In this example, i use customer / order scenario. One customer can have many orders.
There is a one to many realtionship between customer and order entity classes.
The two tables are CUSTOMER and ORDER_TABLE.
Here is the schemas of the tables.
create table CUSTOMER (
ID NUMERIC(10) PRIMARY KEY,
NAME VARCHAR(256)
);
create table ORDER_TABLE (

ORDER_ID NUMERIC PRIMARY KEY,
SHIPPING_ADDRESS VARCHAR(500),
CUSTOMER_ID NUMERIC(10),
FOREIGN KEY (CUSTOMER_ID) REFERENCES CUSTOMER (ID)

);

There is a primary key and foreign key mappings between tables.
Here is the entity classes.
Customer.java
import java.io.Serializable;
import javax.persistence.*;
import static javax.persistence.CascadeType.*;
import java.util.Collection;
import java.util.ArrayList;

@Entity

public class Customer implements Serializable {
private int id;
private String name;
private Collection<Order> orders = new ArrayList<Order>();
@Id
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
@OneToMany(cascade = ALL, mappedBy = "customer")
public Collection<Order> getOrders() {
return orders;
}
public void setOrders(Collection<Order> newValue) {
this.orders = newValue;
}
}

Order.java
import javax.persistence.*;
@Entity
@Table(name = "ORDER_TABLE")
public class Order {
private int id;
private String address;
private Customer customer;
@Id
@Column(name = "ORDER_ID")
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
@Column(name = "SHIPPING_ADDRESS")
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
@ManyToOne()
@JoinColumn(name = "CUSTOMER_ID")
public Customer getCustomer() {
return customer;
}
public void setCustomer(Customer customer) {
this.customer = customer;
}
}

Suppose you are going to insert two orders for a customer, here is the insert(); This is a method that should be in your session bean.
public void insert() {

Customer cust = new Customer();
cust.setId(2);
cust.setName("sujith nishantha");

Order order1 = new Order();
order1.setId(300);
order1.setAddress("123 Main St. Anytown, Sri Lanka");
Order order2 = new Order();
order2.setId(400);
order2.setAddress("567 1st St. Random City, Sri Lanka");
cust.getOrders().add(order1);
order1.setCustomer(cust);
cust.getOrders().add(order2);
order2.setCustomer(cust);
em.persist(cust);
}

This will insert 2 orders for a cutomer.
Here is the select a customer. This method will return a customer object that consists of 2 orders.
public void select() {
Query q =
em.createQuery("select c from Customer c where c.name = :name");
q.setParameter("name", "sujith nishantha");
Collection col = q.getResultList();
System.out.println("size ..... "+col.size());
}

sql of no of count in a value

2009-07-19T23:26:00.000-07:00

select mobile,count(mobile) from table group by mobile

This will return no of counts for a mobile number.

Date comparison in sql

2009-07-17T01:20:00.000-07:00

Here is the sql for date comparison.

select * from table where active_until > added_on

jsp session

2009-07-15T23:27:00.000-07:00

Add this code to the top of the jsp page.

<%@ page import="java.util.*" session="true"%>

Then you can get the session id of the browser and the server.

This id is unique for a browser window.

<% String sessionId=session.getId(); %>

And, you can aloso set your own variable for session. There is a method as "setAttribute".

Use this to set your own attribute for a session.

session.setAttribute("user",username);

how to add an external weblogic server to jdeveloper

2009-06-30T22:06:00.000-07:00

add "Oracle\Middleware\wlserver_10.3\server\lib\weblogic.jar" file to "Oracle\Middleware\jdeveloper\jdev\lib\ext" and restart the jdeveloper.

1) In jdevepoler view menu choose "Application Server Navigator".

2) Then right click on the "Application Servers" and select "New Application Server".

3) Enter weblogic server ip , port, username, password.

4) Enter the weblogic domain as "WLS_Domain";

5)Test your cnnection.

6) Right click on your project select Deploy --> to your weblogic server.

get integer value of a char

2009-06-30T01:34:00.000-07:00

int x = str.charAt(1)

This return the integer values of the char.

ex:-

A = 97

Disable back button in IE using js

2009-06-26T02:55:00.000-07:00

use this code in your page onload method.

window.history.forward(1);

remove unwanted chars (new line,tab) in java

2009-06-14T23:17:00.000-07:00

String truncated = originalString.replaceAll("\\p{Cntrl}", "");

mysal data load and unload

2009-06-08T02:13:00.000-07:00

SELECT * INTO OUTFILE 't1.txt' FIELDS ENCLOSED BY '0' FROM t1;

LOAD DATA INFILE 'LEVEL4.TXT' INTO TABLE HSBC_LEVEL4 FIELDS ENCLOSED BY '|';

Autoboxing and Unboxing in java example

2009-05-15T01:26:00.000-07:00

Java is an Object Oriented programming language. We have to deal with primitive types and objects together.

Here autoboxing comes to play the role. It wraps the primitive data type into a object. There are wrapper classes for it.

For Example : -

public class FormatPrint {

     public static void main(String[] args) {

       System.out.printf("There is only %d thing.", 1);

     }

   }

The signature of the printf() is

printf(String format, Object... args)

But, inthe above example i have printed a integer value. This is called as autoboxing. This can be used in Generics,too.

Here is java normal java generic example : -

import java.util.ArrayList;

   public class ManualBoxing {

     public static void main(String[] args) {

        ArrayList list = new ArrayList();

        for(int i = 0; i < 10; i++){

            list.add(new Integer(i));

        }

     }

   }

But we don't need to "new Integer(i)". We can use autoboxing and simply the code as follow.

import java.util.ArrayList;

    public class Autoboxing {

      public static void main(String[] args) {

          ArrayList<Integer> list = new ArrayList<Integer>();

          for(int i = 0; i < 10; i++){

             list.add(i);

          }

      }

    }

For further details : -

http://java.sun.com/j2se/1.5.0/docs/guide/language/autoboxing.html

Delete non empty directory in java

2009-05-13T01:56:00.000-07:00

import java.io.File;

class DeleteDir {

public static void main(String args[]) {

deleteDirectory(new File(args[0]));

}

static public boolean deleteDirectory(File path) {

if( path.exists() ) {

File[] files = path.listFiles();

for(int i=0; i<files.length; i++) {

if(files[i].isDirectory()) {

deleteDirectory(files[i]);

}

else {

files[i].delete();

}

}

}

return( path.delete() );

}

}

How to log records to log file? Using log4j

2009-04-27T02:41:00.000-07:00

This piece of code will explain the usage of the log4j. In java development, you may have faced for error logging situation. Here is the solution.

Make a log configuration file with follwoing details in your project. Here log configuration file name is "logconfig.txt"

log4j.logger.debugl=INFO,debugl

log4j.appender.debugl.layout=org.apache.log4j.PatternLayout

log4j.appender.debugl=org.apache.log4j.DailyRollingFileAppender

log4j.appender.debugl.File=Log//data_usage_log.txt

log4j.appender.debugl.DatePattern='.'yyyy-MM

log4j.appender.debugl.layout.ConversionPattern=%d{yyyy-MM-dd hh:mm:ss}|%m %n

log4j.appender.debugl.File=c:/data_usage_log.txt

There must be a file called "data_usage_log.txt" in C directory. Then it will upgrade with logs.

Add the following methods to your class constructors.

Logger preLogger

constructor(){

PropertyConfigurator.configure("logconfig.txt");

preLogger = Logger.getLogger("debugl");

}

you can add your error report as follows
preLogger.info(“Logging ”);

Combine two pdf files using itext

2009-04-19T20:52:00.000-07:00

Here is a simple way to combine two pdf files into one.
I have used iText-2.1.5.jar

This is the sample code

import java.io.FileOutputStream;

import com.lowagie.text.pdf.PdfCopyFields;

import com.lowagie.text.pdf.PdfReader;

public class PDFTest {

public static void main(String[] args) throws Exception {

System.out.println("Concatenate Two PDF");

PdfReader reader1 = new PdfReader("D:/upload/first.pdf");

PdfReader reader2 = new PdfReader("D:/upload/second.pdf");

PdfCopyFields copy = new PdfCopyFields(new FileOutputStream("D:/upload/concatenatedPDF.pdf"));

copy.addDocument(reader1);

copy.addDocument(reader2);

copy.close();

}

}

Formatting text on Textarea/ Remove unwanted chars in Textarea

2009-04-16T01:55:00.000-07:00

Direct file access in weblogic server

2009-04-06T22:50:00.000-07:00

In weblogic, you can keep a directory for all images,pdfs,....

how to do ...

------------

you have to create a "weblogic.xml" file in WEB-INF in your application. This weblogic.xml should be like this.

<?xml version="1.0" encoding="UTF-8"?>

<weblogic-web-app>

<virtual-directory-mapping>

<local-path>/apps/test</local-path>

<url-pattern>/images/*</url-pattern>

</virtual-directory-mapping>

</weblogic-web-app>

suppose you have a directory called as images in path /apps/test/images. You can give users to direct access those files as follows.

http://localhost/AppName/images/test.jpeg;

This is called as Virtual directory mapping in weblogic.

Connection pool/jndi

2009-04-06T20:01:00.000-07:00

In normal java development, we use jdbc database connections. It takes several mili seconds to make connection between database server and your application.

In connection pool concept, there are several connections are built with the application server startup. This make web applications more fast.

jndi
------
As i mentioned, it makes several connection at the app sever startup. Developers can access those connections using jndi. There is a jndi for a conncetion pool. All the jndi are in the java jvm.

Developers has to look up for the jndi names and use the database connection.

Suppose your connection pool is "dbtest" . And you have mapped this pool with jndi name "jdbc/dbtest".

your lookup mathod will be like this in netbeans.

private DataSource getDbtest() throws NamingException {
Context c = new InitialContext();
return (DataSource) c.lookup("java:comp/env/dbtest");
}

The above method returns a sql data source. You can get a connection using it.

Ajax + Dwr

2008-12-16T18:51:00.000-08:00

Dwr is a framework for Ajax developers. It is easy to use.

Refer the site for more

<blockquote>http://directwebremoting.org/</blockquote>

Dwr Xml

---------

<blockquote><?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE dwr PUBLIC "-//GetAhead Limited//DTD Direct Web Remoting 0.4//EN" "http://www.getahead.ltd.uk/dwr/dwr.dtd">

<dwr>

<allow>

<create creator="new" javascript="ViewDataJS">

<param name="class" value="com.hylafax.view.ViewData"/>

</create>

<convert converter="bean"

match="com.hylafax.sent.SentDetail"/>

</allow>

</dwr></blockquote>

in dwr xml, create tag creates a new js object of a java class. here "ViewData" java class has been converted to a "ViewDataJS" js script.

convert tag is used to convert object types to js. here "SentDetail" java class objects are converted.

In your jsps

---------------

<blockquote><script type='text/javascript'

src='/Project/dwr/interface/ViewData.js'></script>

<script type='text/javascript'

src='/Project/dwr/engine.js'></script></blockquote>

you have to add dwr jar file to your project. after that you can call your js methods which are in your java class.

you can access your script urls by typing :

http://localhost:8080/Test/dwr

here Test is your project

calling methods in java class

------------------------------

you can call methods like this

ViewDataJS.getReceiveList(division,gotBReceivedFax);

here "division" is the prameter for the getReceiveList method. you can get the results with gotBReceivedFax method.

Free fax server

2008-12-14T18:43:00.000-08:00

Hylafax is a open source fax server written in java. You can configure the sources to use the fax server.

There is client written in java called as "YajHFC".

This is the sample client.

HylaFax Client
----------------

Job job = null;

String user = "test"; // -u
String host = "hyla fax server ip"; // -h
String destination = "destination number"; //
String from = empname; // -f
String killtime = "000259"; // -k
int maxdials = 12; // -T
int maxtries = 3; // -t
int priority = 127; // -P
String notifyaddr = addr; // -f
int resolution = 98; // -l, -m
Dimension pagesize; // -s
String notify = "none";
String pagechop = "default";
int chopthreshold = 3;
Vector documents = new Vector();
boolean verbose = false;
boolean from_is_set = false;

pagesize = Pagesize.A4; // default pagesize is US Letter

HylaFAXClient c = new HylaFAXClient();

try {
c.open(host);
System.out.println("Open host and returned " + c.toString());

if (c.user(user)) {
c.pass("test123");
c.admin("test123");
}

System.out.println("Check point 0:");
c.noop(); // for the heck of it

c.setPassive(true);
c.type(HylaFAXClientProtocol.TYPE_IMAGE);

c.tzone(ClientProtocol.TZONE_LOCAL);
System.out.println("Check point 1");
System.out.println("current directory is: " + c.pwd());

String filename = "/export/home/" + fileName; // where your file located

FileInputStream file = new FileInputStream(filename);
String remote_filename = c.putTemporary(file);

documents.addElement(remote_filename);

job = c.createJob(); // start a new job

// set job properties
job.setFromUser(from);

job.setKilltime(killtime);
job.setMaximumDials(maxdials);
job.setMaximumTries(maxtries);
job.setPriority(priority);
job.setDialstring(destination);
job.setVerticalResolution(resolution);
job.setPageDimension(pagesize);
job.setNotifyType(notify);
job.setChopThreshold(chopthreshold);
job.setNotifyAddress(notifyaddr);

// add documents to the job
for (int i = 0; i < documents.size(); i++) { String document = (String)documents.elementAt(i); job.addDocument(document); } c.submit(job);

java macros

2008-12-03T00:27:00.000-08:00

An enhancement to the JDK7 compiler (the GPL'd version) that adds support for compile-time macros. Macros are Java classes that are instantiated and executed at compile-time. The macros take in a source file's parse tree and a "ParserFactory" that can be used to parse dynamically generated code.
The prototype compiler is fully functional and include a simple proof-of-concept macro. This proof-of-concept macro takes a Java class whose fields have been annotated in a special way and automatically produces getter and setter methods for those annotated fields.
Compile-time macros can be used to implement a variety of additional language features with no further modifications to the compiler. Notable examples include C++-like templates, aspect-oriented programming and closures. Or non-Java languages like Python can be embedded directly in a Java source code comment, and converted to a parse tree at the appropriate time.
This feature was trivial to add. JavaCompiler.parse() was modified to scan the import statements for macros and then execute them on the recently parsed tree. However, this naive implementation, while a good prototype, has several problems.
In the prototype presented here, macros are included in a Java source code program by simply imported the macro class. The compiler scans the parsed source file for import statements, tries to instantiate each imported class, and if the instantiated class implements the Macro interface, it is constructed using a no-argument constructor and executed.
This works but is inefficient. I propose a change to the Java Language Specification, that would re-use the "volatile" keyword for macro declarations. Similar to "import static" for procedural programming, "import volatile" would be used to execute a compile-time macro. This language change is not implemented in the prototype compiler, but it should be trivial to adapt the parser.
Macros currently use the API in com.sun.tools.javac.tree to represent the parse tree. This is suboptimal. The classes in javax.lang.model would be better, but they need to be modified to support full alterations of a parse tree.
Also, failure modes are not robust in the prototype compiler. It is unclear what should happen when a macro throws an exception. Obviously the compiler should generate a parse error for the class being altered by the macro, but the compiler does not yet have the ability to report a stack trace as part of a parse error.
Finally, javadoc was not altered for the prototype. Ideally javadoc would also execute compile-time macros, so that automatically generated members could have full documentation.
As macros exist solely at compile-time, I do not believe this language feature requires any changes to the reflection APIs.
I have rationales. Java is rapidly losing mindshare to dynamic languages like Ruby and Python. Adding compile-time macros can automate many repetitive development tasks while retaining the static safety of Java

Refer
-------

http://code.google.com/p/java-macros/

Convert integer to any base

2008-11-24T18:44:00.000-08:00

System.out.println(Integer.toString(31, 16));

Answer is : 1f

This means 31 into base 16 is 1f.

create temporary table in informix

2008-11-17T19:49:00.000-08:00

create temp table incomplete(id serial," +
"mobile_no varchar(50)," +
"totalNumber integer," +
"repeated integer," +
"achieved varchar(50))WITH NO LOG

when you execute the sql it will make the temporary table "incomplete" in database server temp space with no logs.

when you close the connection this type of table will be dropped. Sometime, you may have to drop it manully too.

How to validate date using js

2008-11-09T18:59:00.000-08:00

Java generics

2008-11-06T18:15:00.000-08:00

Vector <String> vec = new Vector<String>();
if you create a vector like this,
you can only add String objects in to it.
this is simply called as Generics

Value rounding in java

2008-11-06T00:57:00.000-08:00

use the following method to value round in java

double round = 134.23445;
java.text.NumberFormat nf = new java.text.DecimalFormat("0.00");
System.out.println(nf.format(round));
if you need to round a value to three positions
new java.text.DecimalFormat("0.000");

Essential libraries for Jasper developers

2008-11-06T00:34:00.000-08:00

Essential libraries for jasper runtime

commons-collections-2.1.jar
jasperreports-2.0.3.jar
poi-3.0.1-FINAL.jar

Jasper compiler
import java.util.logging.Level;
import java.util.logging.Logger;
import net.sf.jasperreports.engine.JRException;
import net.sf.jasperreports.engine.JasperCompileManager;
public class Main {
public static void main(String[] args) {
try {
System.out.println("compiling");
JasperCompileManager.compileReportToFile("d:\\Complaint.jrxml");
System.out.println("done");
} catch (JRException ex) {
Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
}
}
}