Package ej.event

Class Event

java.lang.Object

ej.event.Event

public class Event
extends java.lang.Object

Event is the object that is sent through the Event Queue. It is either a simple or an extended event. It provides utility methods to read the extended data from an event.

Field Summary

Fields

Modifier and Type	Field	Description
static int	TYPE_MASK

Constructor Summary

Constructors

Constructor	Description
Event(boolean isExtended, int type, int data, byte[] extendedData, int extendedDataLength)	Event constructor.

Method Summary

Modifier and Type	Method	Description
int	available()	Returns the number of bytes that can be read (or skipped over) from extendedData.
int	getMessage()
boolean	isExtended()	Gets the isExtended.
int	read(byte[] b, int off, int len)	Reads len bytes of data from extendedData and store them into the buffer array b.
long	readEightBytes()	Gets the next long (8 bytes) of data from extendedData.
int	readFourBytes()	Gets the next integer (4 bytes) of data from extendedData.
int	readFully(byte[] b)	Reads all the bytes of data from extendedData and store them into the buffer array b.
byte	readOneByte()	Gets the next byte of data from extendedData.
int	readTwoBytes()	Gets the next short (2 bytes) of data from extendedData.
int	skipBytes(int n)	Skips n bytes from extendedData.
void	startRead()	Starts to read an extended data.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

TYPE_MASK

public static final int TYPE_MASK

See Also:

Constant Field Values

Constructor Detail

Event

public Event(boolean isExtended,
             int type,
             int data,
             byte[] extendedData,
             int extendedDataLength)

Event constructor.

Parameters:

isExtended - the kind of event that is sent. Equal to true if it is an extended event.

type - the type of the event.

data - the data of the event. Equal to 0 if it is an extended event.

extendedData - the extended data of the event. Empty if it is a classic event.

extendedDataLength - the number of bytes in extendedData.

Method Detail

isExtended

public boolean isExtended()

Gets the isExtended.

Returns:

the isExtended.

getMessage

public int getMessage()

startRead

public void startRead()

Starts to read an extended data. The offset is set to 0.

readOneByte

public byte readOneByte()
                 throws java.io.IOException

Gets the next byte of data from extendedData. This method is taking C structure alignment into account.

Returns:

the byte value.

Throws:

java.io.IOException - if there is no byte remaining in the data of the extended event.

readTwoBytes

public int readTwoBytes()
                 throws java.io.IOException

Gets the next short (2 bytes) of data from extendedData. This method is taking C structure alignment into account.

Returns:

the short value.

Throws:

java.io.IOException - if there is less than 2 bytes remaining in the data of the extended event.

readFourBytes

public int readFourBytes()
                  throws java.io.IOException

Gets the next integer (4 bytes) of data from extendedData. This method is taking C structure alignment into account.

Returns:

the integer value.

Throws:

java.io.IOException - if there is less than 4 bytes remaining in the data of the extended event.

readEightBytes

public long readEightBytes()
                    throws java.io.IOException

Gets the next long (8 bytes) of data from extendedData. This method is taking C structure alignment into account.

Returns:

the long value.

Throws:

java.io.IOException - if there is less than 8 bytes remaining in the data of the extended event.

readFully

public int readFully(byte[] b)
              throws java.io.IOException

Reads all the bytes of data from extendedData and store them into the buffer array b.

Parameters:

b - the buffer into which the data is read.

Returns:

the total number of bytes read into the buffer.

Throws:

java.io.IOException - if there is no byte remaining in the data of the extended event or if the buffer is too small to store the event data.

read

public int read(byte[] b,
                int off,
                int len)
         throws java.io.IOException

Reads len bytes of data from extendedData and store them into the buffer array b.

Parameters:

b - the buffer into which the data is read.

off - the start offset in array b at which the data is written.

len - the maximum number of bytes to read.

Returns:

the total number of bytes read into the buffer.

Throws:

java.io.IOException - if there are not enough bytes remaining in the data of the extended event or if the buffer is too small to store the event data.

skipBytes

public int skipBytes(int n)

Skips n bytes from extendedData.

Parameters:

n - the number of bytes to skip.

Returns:

0 if OK and -1 if an error occurs.

available

public int available()

Returns the number of bytes that can be read (or skipped over) from extendedData.

Returns:

the number of bytes available in the remaining extended data.