edu.mit.csail.aeolus.api
Class AeolusLock

java.lang.Object
  edu.mit.csail.aeolus.api.AeolusShared
      edu.mit.csail.aeolus.api.AeolusLock

All Implemented Interfaces:

AeolusSafe

public final class AeolusLock
extends AeolusShared

Implementation of a shared lock.

Field Summary

Fields inherited from class edu.mit.csail.aeolus.api.AeolusShared

sharedLastEid

Constructor Summary

AeolusLock()
Construct an AeolusLock with the current thread's labels.

AeolusLock(AeolusLabel sLabel, AeolusLabel iLabel)
Construct an AeolusLock with the specified labels.

Method Summary

void	lock() Blocks until the lock is acquired.
boolean	tryLock() Acquires the lock if it is not currently held and returns true, otherwise returns false.
void	unlock() Releases the lock

Methods inherited from class edu.mit.csail.aeolus.api.AeolusShared

getIntegrityLabel, getSecrecyLabel

Methods inherited from class java.lang.Object

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

Constructor Detail

AeolusLock

public AeolusLock()

Construct an AeolusLock with the current thread's labels.

AeolusLock

public AeolusLock(AeolusLabel sLabel,
                  AeolusLabel iLabel)
           throws InfoFlowControlException

Construct an AeolusLock with the specified labels.

Throws:

InfoFlowControlException - if thread's labels are more constrained than given labels

Method Detail

lock

public void lock()
          throws InfoFlowControlException

Blocks until the lock is acquired.

Throws:

InfoFlowControlException - if the thread can't write the lock

tryLock

public boolean tryLock()
                throws InfoFlowControlException

Acquires the lock if it is not currently held and returns true, otherwise returns false.

Returns:

true if lock acquired, else false

Throws:

InfoFlowControlException - if the thread can't read and write the lock

unlock

public void unlock()
            throws InfoFlowControlException

Releases the lock

Throws:

InfoFlowControlException - if the thread can't write the lock