com.purpletech.message
Class Message

java.lang.Object
  |
  +--com.purpletech.message.Message

All Implemented Interfaces:

Writeable

public class Message

extends java.lang.Object

implements Writeable

A Message is passed between peers

Version:

$Id: Message.java,v 1.2 2001/10/30 12:20:52 alex Exp $

Author:

Alex

Field Summary

static int	ALL peer id number meaning "all clients"
protected java.lang.String	classname
protected java.lang.Object	data contents of message
protected int	from transient id for source of message
static int	MAGIC
static int	NONE peer id number meaning "no client"
protected int	to transient id for destination of message
protected short	type type of message (determines which class to use to deserialize it)
static short	TYPE_BOOLEAN the data object contains a Boolean
static short	TYPE_BYTE the data object contains a Byte
static short	TYPE_BYTES the data object contains a byte array
static short	TYPE_CHAR the data object contains a Character
static short	TYPE_DOUBLE the data object contains a Double
static short	TYPE_FLOAT the data object contains a Float
static short	TYPE_HASHED the data object contains a Writeable, but the name of the writeable is encoded for efficiency (not yet implemented)
static short	TYPE_INT the data object contains a Integer
static short	TYPE_LONG the data object contains a Long
static short	TYPE_SHORT the data object contains a Short
static short	TYPE_STRING the data object contains a String
static short	TYPE_SYSTEM the data object contains a SystemData object
static short	TYPE_WRITEABLE the data object contains a Writeable
protected long	whenCreated msec since epoch when it was created

Constructor Summary

	Message(java.io.DataInputStream in)
	Message(java.io.InputStream in)
	Message(int from, int to, byte[] data) Initialize this object.
	Message(int from, int to, java.lang.Number data)
	Message(int from, int to, java.lang.String data)
	Message(int from, int to, SystemData data)
	Message(int from, int to, Writeable data)
	Message(Message m) copy constructor
	Message(Message m, boolean copyWhenCreated) copy constructor
protected	Message(short type, int from, int to, java.lang.String classname, java.lang.Object data) standard constructor

Method Summary

java.lang.String	getClassName()
java.lang.Object	getData()
java.io.DataInputStream	getDataInputStream() only makes sense with TYPE_BYTES
java.io.DataOutputStream	getDataOutputStream() returns a DataOutputStream that stores its bytes into this Message's data property.
int	getFrom()
java.io.InputStream	getInputStream()
int	getInt() Alternate accessor -- get data as int
java.io.OutputStream	getOutputStream() returns an OutputStream that stores its bytes into this Message's data property.
java.lang.String	getString() Alternate accessor -- get data as string
int	getTo()
short	getType()
long	getWhenCreated() returns the time the message was constructed, in the local time of the local machine
protected static short	numberToType(java.lang.Number data)
void	read(java.io.DataInputStream in) Read a message from a stream.
protected void	read(java.io.InputStream in) Read a message from a stream.
static Message	readMessage(java.io.DataInputStream in) Factory method.
void	setData(int x) Alternate mutator -- set data as int
void	setData(java.lang.Object data)
void	setFrom(int from)
void	setTo(int to)
java.lang.String	toString()
void	write(java.io.DataOutputStream out) Write this message to a stream
void	write(java.io.OutputStream out) Write this message to a stream

Methods inherited from class java.lang.Object

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

Field Detail

ALL

public static final int ALL

peer id number meaning "all clients"

See Also:

Constant Field Values

NONE

public static final int NONE

peer id number meaning "no client"

See Also:

Constant Field Values

MAGIC

public static final int MAGIC

See Also:

Constant Field Values

TYPE_BYTES

public static final short TYPE_BYTES

the data object contains a byte array

See Also:

Constant Field Values

TYPE_BOOLEAN

public static final short TYPE_BOOLEAN

the data object contains a Boolean

See Also:

Constant Field Values

TYPE_BYTE

public static final short TYPE_BYTE

the data object contains a Byte

See Also:

Constant Field Values

TYPE_SHORT

public static final short TYPE_SHORT

the data object contains a Short

See Also:

Constant Field Values

TYPE_CHAR

public static final short TYPE_CHAR

the data object contains a Character

See Also:

Constant Field Values

TYPE_INT

public static final short TYPE_INT

the data object contains a Integer

See Also:

Constant Field Values

TYPE_LONG

public static final short TYPE_LONG

the data object contains a Long

See Also:

Constant Field Values

TYPE_FLOAT

public static final short TYPE_FLOAT

the data object contains a Float

See Also:

Constant Field Values

TYPE_DOUBLE

public static final short TYPE_DOUBLE

the data object contains a Double

See Also:

Constant Field Values

TYPE_STRING

public static final short TYPE_STRING

the data object contains a String

See Also:

Constant Field Values

TYPE_WRITEABLE

public static final short TYPE_WRITEABLE

the data object contains a Writeable

See Also:

Constant Field Values

TYPE_HASHED

public static final short TYPE_HASHED

the data object contains a Writeable, but the name of the writeable is encoded for efficiency (not yet implemented)

See Also:

Constant Field Values

TYPE_SYSTEM

public static final short TYPE_SYSTEM

the data object contains a SystemData object

See Also:

Constant Field Values

type

protected short type

type of message (determines which class to use to deserialize it)

classname

protected java.lang.String classname

from

protected int from

transient id for source of message

to

protected int to

transient id for destination of message

data

protected java.lang.Object data

contents of message

whenCreated

protected long whenCreated

msec since epoch when it was created

Constructor Detail

Message

protected Message(short type,
                  int from,
                  int to,
                  java.lang.String classname,
                  java.lang.Object data)

standard constructor

Message

public Message(Message m)

copy constructor

Message

public Message(Message m,
               boolean copyWhenCreated)

copy constructor

Message

public Message(int from,
               int to,
               byte[] data)

Initialize this object.

Message

public Message(int from,
               int to,
               java.lang.String data)

Message

public Message(int from,
               int to,
               java.lang.Number data)

Message

public Message(int from,
               int to,
               SystemData data)

Message

public Message(int from,
               int to,
               Writeable data)

Message

public Message(java.io.DataInputStream in)
        throws java.io.IOException

Message

public Message(java.io.InputStream in)
        throws java.io.IOException

Method Detail

numberToType

protected static short numberToType(java.lang.Number data)

getType

public short getType()

Returns:

the type of message

getFrom

public int getFrom()

Returns:

which (transient, server-specific) peer created this message

setFrom

public void setFrom(int from)

Parameters:

from - which (transient, server-specific) peer created this message

getTo

public int getTo()

Returns:

which (transient, server-specific) peer will receive this message

setTo

public void setTo(int to)

Parameters:

to - which (transient, server-specific) peer will receive this message

getData

public java.lang.Object getData()

Returns:

the data attached to this message

setData

public void setData(java.lang.Object data)

getWhenCreated

public long getWhenCreated()

returns the time the message was constructed, in the local time of the local machine

getString

public java.lang.String getString()

Alternate accessor -- get data as string

getInt

public int getInt()

Alternate accessor -- get data as int

setData

public void setData(int x)

Alternate mutator -- set data as int

getInputStream

public java.io.InputStream getInputStream()

Returns:

an InputStream that returns this message's data bytes.

getDataInputStream

public java.io.DataInputStream getDataInputStream()

only makes sense with TYPE_BYTES

Returns:

a DataInputStream that returns this message's data bytes

getDataOutputStream

public java.io.DataOutputStream getDataOutputStream()

returns a DataOutputStream that stores its bytes into this Message's data property. Calling close() on the stream finishes the process. (Before you call close, the data has not been set.) This forces the type to be TYPE_BYTES.

getOutputStream

public java.io.OutputStream getOutputStream()

returns an OutputStream that stores its bytes into this Message's data property. Calling close() on the stream finishes the process. (Before you call close, the data has not been set.) This forces the type to be TYPE_BYTES.

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

write

public void write(java.io.OutputStream out)
           throws java.io.IOException

Write this message to a stream

java.io.IOException

write

public void write(java.io.DataOutputStream out)
           throws java.io.IOException

Write this message to a stream

Specified by:

write in interface Writeable

java.io.IOException

read

protected void read(java.io.InputStream in)
             throws java.io.IOException

Read a message from a stream. This method is protected; use the factory method readMessage() instead.

java.io.IOException

See Also:

readMessage(java.io.DataInputStream)

read

public void read(java.io.DataInputStream in)
          throws java.io.IOException

Read a message from a stream. This method should be protected; use the factory method readMessage() instead. (It can't be protected because it's public in the interface.)

Specified by:

read in interface Writeable

java.io.IOException

See Also:

readMessage(java.io.DataInputStream)

getClassName

public java.lang.String getClassName()

Specified by:

getClassName in interface Writeable

readMessage

public static Message readMessage(java.io.DataInputStream in)
                           throws java.io.IOException

Factory method. This is the preferred way of reading the next message from a stream.

java.io.IOException