jcsp.lang
Interface ChannelOutput

All Known Subinterfaces:

Channel

All Known Implementing Classes:

BlackHoleChannel

public interface ChannelOutput

This defines the interface for writing to object channels.

Description

ChannelOutput defines the interface for writing to object channels. The interface contains only one method - write(Object o). This method will block the calling process until the Object has been accepted by the channel. In the (default) case of a zero-buffered synchronising CSP channel, this happens only when a process at the other end of the channel invokes (or has already invoked) a read().

ChannelOutput variables are used to hold channels that are going to be used only for output by the declaring process. This is a security matter -- by declaring a ChannelOutput interface, any attempt to input from the channel will generate a compile-time error. For example, the following code fragment will not compile:

 Object doRead (ChannelOutput c) {
   return c.read ();   // illegal
 }
 

When configuring a CSProcess with output channels, they should be declared as ChannelOutput variables. The actual channel passed, of course, may belong to any channel class that implements ChannelOutput.

Instances of any class may be written to a channel.

Example

 void doWrite (ChannelOutput c, Object o) {
   c.write (o);
 }
 

Author:

P.D.Austin

See Also:

ChannelInput

Method Summary

void	write(Object object) Write an Object to the channel.

Method Detail

write

public void write(Object object)

Write an Object to the channel.

Parameters:

object - the object to write to the channel