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Threads accessing a program

 
Ranch Hand
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Hi

I have a question which needs some expert advise . I have a class which looks like this

class A
{

public int i = 0;

public int read()
{
return i;
}

public void write()
{
i++;
}
}

This program needs to be modified in a such a way that

1. Two threads should be able to read the value of i
2. Two threads should not be able to write at a time
3. Read should not be allowed when write is happening because of some thread

Can any one let me know the best way of doing this ??
 
author
Posts: 23909
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This is hardly an advanced topic. In fact, it seems more like a homework questions. Anyway, the Sun tutorial on synchronization should be a good point for you to start.

Henry
 
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Hi there,

I am no expert by if you are using JDK 1.5 there is an easy way of doing that.

Take a look at the ReentranteadWriteLock class and the ReadWriteLock interface.

Using the methods there you can easily implement your criteria.
 
author and iconoclast
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Moving to "Threads and Synchronization."
 
Don't get me started about those stupid light bulbs.
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