Java Code For Binary Hexadecimal Conversion

In this post code for binary to hex coversion has been posted. This is pure java code and can be used in BlackBerry, J2ME and Java.

/**
* This class provides funcationlity to convert binary byte array to hexadecimal byte array as
* well as to convert hexadecimal byte array to binary byte array.
*/
public class BinHexConverter
{
private static String HEX_STRING = "0123456789ABCDEF";

public static byte[] convertHexToBinary(byte[] hex)
{
int block = 0;

byte[] data = new byte[hex.length / 2];

int index = 0;
boolean next = false;

for (int i=0; i<<= 4; int pos = HEX_STRING.indexOf(Character.toUpperCase((char) hex[i])); if (pos > -1)
{
block += pos;
}

if (next)
{
data[index] = (byte)(block & 0xff );
index++;
next = false;
}
else
{
next = true;
}
}

return data;
}

private static String convertBinary2Hex(byte[] binary)
{
StringBuffer buf = new StringBuffer();

int block = 0;

for (int i=0; i> 4));
buf.append(HEX_STRING.charAt(binary[i] & 0x0F));
}

return buf.toString();
}
}

/**
* Test class for binary to hex conversion.
*/
public class BinHexTester
{
public static void main(String[] args)
{
String strText = BinHexConverter.convertBinary2Hex("hellohello".getBytes());
System.out.println(strText);
}
}

PIM Listener Blackberry

Blackberry provides PIMListener to get notification regarding changes in the PIMItems. Following is a library class created to get notification regarding changes in contact, task, appointment and/or memo on blackberry device.

1. Create object of BBPIMListener.
2. Start listening for specified PIM types by calling method 'fnAddListener()'. Multiple types can be specified by using | (OR) operator. e.g. fnAddListener(BBPIMListener.CONTACT_LIST | BBPIMListener.MEMO_LIST)
3. Override methods to provide specific functionality. e.g. override method 'fnOnContactAdded()' to specify what has to be done on contact addition.

Here is code:

import net.rim.blackberry.api.pdap.*;
import javax.microedition.pim.*;
import java.util.*;

/**
* Library class for listening changes in contact list, task list, appointments
* and/or memos.
*
* @author Dipak
*/
public class BBPIMListener implements PIMListListener
{
public final int CONTACT_LIST = 1;
public final int TASK_LIST = 2;
public final int APPOINTMENT_LIST = 4;
public final int MEMO_LIST = 8;

public final int ADD = 1;
public final int DELETE = 2;
public final int UPDATE = 4;

private BlackBerryPIMList m_oContactList;
private BlackBerryPIMList m_oToDoList;
private BlackBerryPIMList m_oEventList;
private BlackBerryPIMList m_oMemoList;

/**
* Adds listener for specified PIM types and gives information related to
* changes in those.
* @param nType List type; one of CONTACT_LIST, TASK_LIST, APPOINTMENT_LIST,
* MEMO_LIST
*/
public void fnAddListener(int nType)
{
try
{
PIM oPIM = PIM.getInstance();

if(CONTACT_LIST == (nType & CONTACT_LIST))
{
// Contact listener
m_oContactList = (BlackBerryPIMList)oPIM.openPIMList(PIM.CONTACT_LIST, PIM.READ_WRITE);
m_oContactList.addListener(this);
}

if(TASK_LIST == (nType & TASK_LIST))
{
// Task listener
m_oToDoList = (BlackBerryPIMList)oPIM.openPIMList(PIM.TODO_LIST, PIM.READ_WRITE);
m_oToDoList.addListener(this);
}

if(APPOINTMENT_LIST == (nType & APPOINTMENT_LIST))
{
// Calendar listener
m_oEventList = (BlackBerryPIMList)oPIM.openPIMList(PIM.EVENT_LIST, PIM.READ_WRITE);
m_oEventList.addListener(this);
}

if(MEMO_LIST == (nType & MEMO_LIST))
{
// Memo listener
m_oMemoList = (BlackBerryMemoList)oPIM.openPIMList(BlackBerryPIM.MEMO_LIST, PIM.READ_WRITE);
m_oMemoList.addListener(this);
}
}
catch(PIMException e)
{
e.printStackTrace();
}
}

/**
* Removes listener added to the list specified by the user.
*/
public void fnRemoveListener()
{
if(null != m_oContactList)
{
m_oContactList.removeListener(this);
}

if(null != m_oToDoList)
{
m_oToDoList.removeListener(this);
}

if(null != m_oEventList)
{
m_oEventList.removeListener(this);
}

if(null != m_oMemoList)
{
m_oMemoList.removeListener(this);
}
}

// Occurs when an item is added to the PIM list.
public void itemAdded(PIMItem oItem)
{
fnNotifyPIMChange(ADD, null, oItem);
}

// Occurs when an item is removed from the PIM list.
public void itemRemoved(PIMItem oItem)
{
fnNotifyPIMChange(DELETE, null, oItem);
}

// Occurs when an item is updated within the PIM list.
public void itemUpdated(PIMItem oOldItem, PIMItem oNewItem)
{
fnNotifyPIMChange(UPDATE, oOldItem, oNewItem);
}

private void fnNotifyPIMChange(int nOperation, PIMItem oOldItem, PIMItem oNewItem)
{
if(oNewItem instanceof Contact)
{
switch(nOperation)
{
case ADD:
{
fnOnContactAdded((Contact)oNewItem);
break;
}
case DELETE:
{
fnOnContactDeleted((Contact)oNewItem);
break;
}
case UPDATE:
{
fnOnContactUpdated((Contact)oOldItem, (Contact)oNewItem);
break;
}
}
}
else if(oNewItem instanceof ToDo)
{
switch(nOperation)
{
case ADD:
{
fnOnTaskAdded((ToDo)oNewItem);
break;
}
case DELETE:
{
fnOnTaskDeleted((ToDo)oNewItem);
break;
}
case UPDATE:
{
fnOnTaskUpdated((ToDo)oOldItem, (ToDo)oNewItem);
break;
}
}
}
else if(oNewItem instanceof Event)
{
switch(nOperation)
{
case ADD:
{
fnOnAppointmentAdded((Event)oNewItem);
break;
}
case DELETE:
{
fnOnAppointmentDeleted((Event)oNewItem);
break;
}
case UPDATE:
{
fnOnAppointmentUpdated((Event)oOldItem, (Event)oNewItem);
break;
}
}
}
else if(oNewItem instanceof BlackBerryMemo)
{
switch(nOperation)
{
case ADD:
{
fnOnMemoAdded((BlackBerryMemo)oNewItem);
break;
}
case DELETE:
{
fnOnMemoDeleted((BlackBerryMemo)oNewItem);
break;
}
case UPDATE:
{
fnOnMemoUpdated((BlackBerryMemo)oOldItem, (BlackBerryMemo)oNewItem);
break;
}
}
}
}

/**
* Occurs when contact is added to contact list.
* @param oItem Contact that is added to the contact list.
*/
public void fnOnContactAdded(Contact oContact)
{
}

/**
* Occurs when Contact is deleted from contact list.
* @param oItem Contact that is deleted from the contact list.
*/
public void fnOnContactDeleted(Contact oContact)
{
}

/**
* Occurs when Contact is updated in contact list.
* @param oOldItem State of Contact before update.
* @param oNewItem New state of Contact as a result of update.
*/
public void fnOnContactUpdated(Contact oOldContact, Contact oNewContact)
{
}

/**
* Occurs when ToDo(i.e. task) is added to task list.
* @param oItem ToDo(i.e. task) that is added to the task list.
*/
public void fnOnTaskAdded(ToDo oToDo)
{
}

/**
* Occurs when ToDo(i.e. task) is deleted from task list.
* @param oItem ToDo(i.e. task) that is deleted from the task list.
*/
public void fnOnTaskDeleted(ToDo oToDo)
{
}

/**
* Occurs when ToDo(i.e. task) is updated in task list.
* @param oOldItem State of ToDo(i.e. task) before update.
* @param oNewItem New state of ToDo(i.e. task) as a result of update.
*/
public void fnOnTaskUpdated(ToDo oOldToDo, ToDo oNewToDo)
{
}

/**
* Occurs when Event(i.e. appointment) is added to appointment list.
* @param oItem Event(i.e. appointment) that is added to the appointment list.
*/
public void fnOnAppointmentAdded(Event oEvent)
{
}

/**
* Occurs when Event(i.e. appointment) is deleted from appointment list.
* @param oItem Event(i.e. appointment) that is deleted from the appointment list.
*/
public void fnOnAppointmentDeleted(Event oEvent)
{
}

/**
* Occurs when Event(i.e. appointment) is updated in appointment list.
* @param oOldItem State of Event(i.e. appointment) before update.
* @param oNewItem New state of Event(i.e. appointment) as a result of update.
*/
public void fnOnAppointmentUpdated(Event oOldEvent, Event oNewEvent)
{
}

/**
* Occurs when BlackBerryMemo(i.e. memo) is added to memo list.
* @param oItem BlackBerryMemo(i.e. memo) that is added to the memo list.
*/
public void fnOnMemoAdded(BlackBerryMemo oBlackBerryMemo)
{
}

/**
* Occurs when BlackBerryMemo(i.e. memo) is deleted from memo list.
* @param oItem BlackBerryMemo(i.e. memo) that is deleted from the memo list.
*/
public void fnOnMemoDeleted(BlackBerryMemo oBlackBerryMemo)
{
}

/**
* Occurs when BlackBerryMemo(i.e. memo) is updated in memo list.
* @param oOldItem State of BlackBerryMemo(i.e. memo) before update.
* @param oNewItem New state of BlackBerryMemo(i.e. memo) as a result of update.
*/
public void fnOnMemoUpdated(BlackBerryMemo oOldBlackBerryMemo, BlackBerryMemo oNewBlackBerryMemo)
{
}
}