JAVA-BASED REAL-TIME PROGRAMMING

3. Multi-Threaded Programming
int currentSize()
public int getMaxSize()
void setMaxSize(int newSize)
Other protected fields Apart from the protected buffer array and object
lock described above, the following are the other fields for subclass usage.
First there are the indexes for reading respectively writing as shown in
Figure 3-10, as well as the current size:
int currSize;
int postAt;
int fetchAt;
There are two fields for keeping the maximum size. It is the maxSizeW
that is the requested maximum size. The maxSizeR can temporarily
during shrinkage (resizing equal to true) of a too large buffer be greater
than maxSizeW, but they will have the same value during normal operation
(when resizing equals false).
int maxSizeR;
int maxSizeW;
boolean resizing;
Threads that are interrupted during (or prior to) blocking are thrown
an RTInterrupted error.
Referring to buffer input or output
Sometimes it is desirable to have an object that represents only one end of a
buffer. For the RTEventBuffer, utilizing Java interfaces, this is accomplished
by one interface for input containing the post methods, and one interface for
output containing the methods for fetching events. Thus,
class RTEventBuffer implements RTEventBufferInput , RTEventBufferOutput
where these interfaces are defined as
interface RTEventBufferInput {
RTEvent post(RTEvent e);
void doPost(RTEvent e);
RTEvent tryPost(RTEvent e);
RTEvent tryPost(RTEvent e, long timeout);
RTEvent tryPost(RTEvent e, long timeout , int nanos);
}
interface RTEventBufferOutput {
RTEvent fetch();
RTEvent doFetch();
RTEvent tryFetch();
RTEvent tryFetch(long timeout);
RTEvent tryFetch(long timeout , int nanos);
}
Refer to the RTEventBuffer above for a description of the methods. Using
these interfaces you can for instance have the output of a buffer managed
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