Programming, Database, Wireless, GPS etc

Carta Organisasi TKI

2009-07-03T22:24:00.001+08:00

Masukkan carta organisasi di sini.

Java: Distinct List Function

2008-08-27T22:42:00.005+08:00

The below java function will distinct a list of string that splitted by coma.

For example:
If input = A,A,B,B,C
This function will return A,B,C in Vector type.

Vector DistinctList(String lists){
   int a=0;
   int i=0,j=0,k=0;
   boolean dup = false;
   Vector vPreConCols = new Vector();
   String[] L1 = split(lists,",");    vPreConCols.add(L1[0]);
   a=1;
    for(i=1; i<L1.length; i++){
       j=0;
          while((j<a)&&(dup==false)){
            if(L1[i].equalsIgnoreCase(vPreConCols.get(j).toString())){
                dup=true;
            }
            j+=1;
         }
          if(!dup){
            vPreConCols.add(L1[i]);
         a+=1;
          }
   }
return vPreConCols;
}

Jsp: Set Browser Expired Time

2008-08-21T21:50:00.005+08:00

Command:
session.setMaxInactiveInterval(int intSecond);
intSecond -> time in second

Example:
session.setMaxInactiveInterval(10);

Description:
The browser will expire within 10 seconds

Java: Increase Heap Size to prevent java.lang.OutOfMemoryError

2008-08-17T19:22:00.003+08:00

java -Xms -Xmx Eg: java -Xms32m -Xmx128m javaFileName
* By default the maximum heap size = 128 mb

Java: Redirect Java Output to a File

2008-08-10T01:52:00.002+08:00

In order to redirect the java standard output to a file, we need to use the greater-than-sign (>) character followed by a filename after java.exe on a command line.
For example:
java Hello > D:\output.txt
This will redirect the output of System.out.println() to output.txt file

Java: Get Current Directory

2008-08-09T13:13:00.002+08:00

import java.io.File;
   public class CurrentDir {
      public static void main (String args[]) {
         File dir1 = new File (".");
         File dir2 = new File ("..");
         try {
            System.out.println ("Current dir : " + dir1.getCanonicalPath());
            System.out.println ("Parent dir : " + dir2.getCanonicalPath());
         }
         catch(Exception e) {
            e.printStackTrace();
         }
      }
}

Java: Rename a file

2008-08-09T12:03:00.002+08:00

import java.io.*;

public class ListFile {
   public static void main(String args[]){
         ListFile lstFile = new ListFile();
         System.out.println(lstFile.renameFile("D:/test/nasatest.txt"));
   }

   public boolean renameFile(String file){
         File oldFile = new File(file);
         File newFile = new File("D:/test/nasa.txt");
         boolean success = false;
         // Rename file (or directory)
         try{
               success = oldFile.renameTo(newFile);
         }catch(Exception e){
               e.printStackTrace();
         }
         return success;
   }
}

Java: Download files from HTTP

2008-08-02T09:48:00.002+08:00

import java.io.*;
import java.net.*;
/*
* Command line program to download data from URLs and save
* it to local files. Run like this:
* java FileDownload http://schmidt.devlib.org/java/file-download.html
* @author Marco Schmidt
*/
public class FileDownload {
   public static void download(String address, String localFileName) {
      OutputStream out = null;
      URLConnection conn = null;
      InputStream in = null;
      try {
         URL url = new URL(address);
         out = new BufferedOutputStream(
         new FileOutputStream(localFileName));
         conn = url.openConnection();
         in = conn.getInputStream();
         byte[] buffer = new byte[1024];
         int numRead;
         long numWritten = 0;
         while ((numRead = in.read(buffer)) != -1) {
            out.write(buffer, 0, numRead);
            numWritten += numRead;
         }
         System.out.println(localFileName + "\t" + numWritten);
      } catch (Exception exception) {
         exception.printStackTrace();
      } finally {
         try {
            if (in != null) {
               in.close();
            }
            if (out != null) {
               out.close();
            }
         } catch (IOException ioe) {
         }
      }
   }

   public static void download(String address) {
      int lastSlashIndex = address.lastIndexOf('/');
      if (lastSlashIndex >= 0 &&
      lastSlashIndex < address.length() - 1) {
         download(address, address.substring(lastSlashIndex + 1));
      } else {
         System.err.println("Could not figure out local file name for " +
address);
         }
      }

   public static void main(String[] args) {
      for (int i = 0; i < args.length; i++) {
         download(args[i]);
      }
   }
}

Reference: http://schmidt.devlib.org

Java: Delete files in a directory

2008-08-02T09:42:00.001+08:00

public void deleteFiles(){
   java.io.File file = new java.io.File("d:\\test");
   java.io.File[] f = file.listFiles();
   for (int i = 0; i < f.length; i++) {
      f[i].delete();
   }
}

Java: Date Format

2008-07-27T11:07:00.005+08:00

Code Sample:

import java.text.SimpleDateFormat;

java.util.Date today = new java.util.Date();
SimpleDateFormat sdfOutput = new SimpleDateFormat ( "yyyyMMdd" );
String strToday = sdfOutput.format( today );

Date and Time Patterns as below:

Letter: G
Date or Time Component: Era designator
Presentation: Text
Examples: AD

Letter: y
Date or Time Component: Year
Presentation: Year
Examples: 1996; 96

Letter: M
Date or Time Component: Month in year
Presentation: Month
Examples: July; Jul; 07

Letter: w
Date or Time Component: Week in year
Presentation: Number
Examples: 27

Letter: W
Date or Time Component: Week in month
Presentation: Number
Examples: 2

Letter: D
Date or Time Component: Day in year
Presentation: Number
Examples: 189

Letter: d
Date or Time Component: Day in month
Presentation: Number
Examples: 10

Letter: F
Date or Time Component: Day of week in month
Presentation: Number
Examples: 2

Letter: E
Date or Time Component: Day in week
Presentation: Text
Examples: Tuesday; Tue

Letter: a
Date or Time Component: Am/pm marker
Presentation: Text
Examples: PM

Letter: H
Date or Time Component: Hour in day (0-23)
Presentation: Number
Examples: 0

Letter: k
Date or Time Component: Hour in day (1-24)
Presentation: Number
Examples: 24

Letter: K
Date or Time Component: Hour in am/pm (0-11)
Presentation: Number
Examples: 0

Letter: h
Date or Time Component: Hour in am/pm (1-12)
Presentation: Number
Examples: 12

Letter: m
Date or Time Component: Minute in hour
Presentation: Number
Examples: 30

Letter: s
Date or Time Component: Second in minute
Presentation: Number
Examples: 55

Letter: S
Date or Time Component: Millisecond
Presentation: Number
Examples: 978

Letter: z
Date or Time Component: Time zone
Presentation: General time zone
Examples: Pacific Standard Time; PST; GMT-08:00

Letter: Z
Date or Time Component: Time zone
Presentation: RFC 822 time zone
Examples: -0800

Examples
Date and Time Pattern: "yyyy.MM.dd G 'at' HH:mm:ss z"
Result: 2001.07.04 AD at 12:08:56 PDT

Date and Time Pattern: "yyyy.MM.dd G 'at' HH:mm:ss z"
Result: Wed, Jul 4, '01

Date and Time Pattern: "h:mm a"
Result: 12:08 PM

Date and Time Pattern: "hh 'o''clock' a, zzzz"
Result: 12 o'clock PM, Pacific Daylight Time

Date and Time Pattern: "K:mm a, z"
Result: 0:08 PM, PDT

Date and Time Pattern: "yyyyy.MMMMM.dd GGG hh:mm aaa"
Result: 02001.July.04 AD 12:08 PM

Date and Time Pattern: "EEE, d MMM yyyy HH:mm:ss Z"
Result: Wed, 4 Jul 2001 12:08:56 -0700

Date and Time Pattern: "yyMMddHHmmssZ"
Result: 010704120856-0700

Date and Time Pattern: "yyyy-MM-dd'T'HH:mm:ss.SSSZ"
Result: 2001-07-04T12:08:56.235-0700

Java: Compare 2 dates

2008-07-26T20:08:00.000+08:00

import java.util.Date;

public class CompareDate {
   public static void main(String[] args) {
      Date dt2 = new Date("7/26/2004");
      Date dt3 = new Date("7/25/2004");

      if (dt2.compareTo(dt3) > 0) {
         System.out.println("dt2>dt3");
      } else {
         System.out.println("dt3<=dt2");
      }
   }
}

Java: Check server response

2008-07-26T19:10:00.004+08:00

Java Version 1.4

try
{
   java.net.Socket s = new Socket();
   s.connect(new InetSocketAddress("192.168.0.157", 7777), 1000);
   s.close();
   System.out.println("Success");
}catch (Exception ex){
   System.out.println("Error : " + ex.getMessage());
   // failed
   // do redirect
}

Java Version 1.3

try{
   java.net.Socket s = new Socket(host, port);
   s.close();
}catch (Exception ex){
   // failed
   // do redirect
}

Java: Cast ArrayList to Array

2008-07-26T18:08:00.000+08:00

import java.util.ArrayList;

public class CastAryListToArray {
   public static void main(String arg[]){
   //How to cast ArrayList to Array
   //The following code will store arraylist value into array:
   ArrayList al = new ArrayList();
   al.add("a");
   al.add("b");
   al.add("c");
   String XAxisValue[] = new String[al.size()];
   al.toArray(XAxisValue);
   
   for(int i=0;i<XAxisValue.length;i++){
      System.out.println("XAxisValue["+i+"] = " + XAxisValue[i]);
   }
 }
}

Java: Call an Oracle Stored Procedure

2008-07-26T16:35:00.000+08:00

/*

* This sample shows how to call a PL/SQL stored procedure using the SQL92

* syntax.

*/

import java.sql.*;
import java.io.*;

class PLSQLExample {
public static void main(String args[]) throws SQLException, IOException {
// Load the driver
DriverManager.registerDriver(new oracle.jdbc.driver.OracleDriver());

// Connect to the database
// You can put a database name after the @ sign in the connection URL.
Connection conn = DriverManager.getConnection("jdbc:oracle:thin:@192.168.0.157:1521:mydb",
"scott", "tiger");

// Create a statement
Statement stmt = conn.createStatement();

// Create the stored function
stmt.execute("create or replace function RAISESAL (name CHAR, raise NUMBER)return
NUMBER is begin return raise + 100000; end;");

// Close the statement
stmt.close();

// Prepare to call the stored procedure RAISESAL.
// This sample uses the SQL92 syntax
CallableStatement cstmt = conn.prepareCall("{? = call RAISESAL (?, ?)}");

// Declare that the first ? is a return value of type Int
cstmt.registerOutParameter(1, Types.INTEGER);

// We want to raise LESLIE's salary by 20,000
cstmt.setString(2, "LESLIE");

// The name argument is the second ?
cstmt.setInt(3, 20000);

// The raise argument is the third ?
// Do the raise
cstmt.execute();

// Get the new salary back
int new_salary = cstmt.getInt(1);
System.out.println("The new salary is: " + new_salary);

// Close the statement
cstmt.close();

// Close the connection
conn.close();
}
}

Java: 2D Array Declaration

2008-07-26T15:59:00.000+08:00

//2D Array declaration
int array1[][] = new int [2][2];

//2D Array assignment
array1[0][0] = 1;
array1[0][1] = 2;
array1[1][0] = 3;
array1[1][1] = 4;

//Print 2D Array
for(int i=0;i<2;i++){
for(int j=0;j<2;j++){
System.out.println(array1[i][j]);
}
}