Field Detail

• static final int DEFAULT_CONCURRENCY_LEVEL

• static final int DEFAULT_INITIAL_CAPACITY

• static final float DEFAULT_LOAD_FACTOR

• private static final DataflowVariable<java.lang.Object> DUMMY

• private final java.lang.Object lock

• @java.lang.SuppressWarnings({"FieldAccessedSynchronizedAndUnsynchronized"}) private java.util.concurrent.ConcurrentMap<java.lang.Object, DataflowVariable<java.lang.Object>> variables

Constructor Detail

• public Dataflows(int initialCapacity, float loadFactor, int concurrencyLevel)

  Constructor that supports the various constructors of the underlying ConcurrentHashMap (unless the one with Map parameter).

  throws:

  IllegalArgumentException if the initial capacity is negative or the load factor or concurrencyLevel are non-positive.

  Parameters:

  initialCapacity - the initial capacity. The implementation performs internal sizing to accommodate this many elements.

  loadFactor - the load factor threshold, used to control resizing. Resizing may be performed when the average number of elements per bin exceeds this threshold.

  concurrencyLevel - the estimated number of concurrently updating threads. The implementation performs internal sizing to try to accommodate this many threads.

  See Also:

  java.util.concurrent.ConcurrentHashMap

• public Dataflows()

  Constructor with default values for building the underlying ConcurrentHashMap

  See Also:

  java.util.concurrent.ConcurrentHashMap

Method Detail

• public boolean contains(java.lang.Object name)

  Checks whether a certain key is contained in the map. Doesn't check, whether the variable has already been bound.

  Returns:

  A DFV is exists, or null

  Parameters:

  name - The name of the DFV to check.

• private DataflowVariable<java.lang.Object> ensureToContainVariable(java.lang.Object name)

  The idea is following:

  • we try to putIfAbsent dummy DFV in to map
  • if something real already there we are done
  • if not we obtain lock and put new DFV with double check

  Unfortunately we have to sync on this as there is no better option (God forbid to sync on name)

  Returns:

  DataflowVariable corresponding to name

  Parameters:

  name - The key to ensure has a DFV bound to it

• @java.lang.SuppressWarnings({"AutoBoxing"}) java.lang.Object getAt(int index)

  Retrieves the DFV associated with the given index

  throws:

  InterruptedException If the thread gets interrupted

  Returns:

  the value of the DataflowVariable associated with the property "index". May block if the value is not scalar.

  Parameters:

  index - The index to find a match for

  See Also:

  DataflowVariable.getVal

• @java.lang.Override public java.lang.Object getProperty(java.lang.String property)

  Returns:

  the value of the DataflowVariable associated with the property "name". May block if the value is not scalar.

  See Also:

  DataflowVariable.getVal

• @java.lang.Override public java.lang.Object invokeMethod(java.lang.String name, java.lang.Object args)

  Invokes the given method. Allows for invoking whenBound() on the dataflow variables.

   def df = new Dataflows()
   df.var {*     println "Variable bound to $it"
   }* 

  Returns:

  the result of invoking the method (void)

  Parameters:

  name - the name of the method to call (the variable name)

  args - the arguments to use for the method call (a closure to invoke when a value is bound)

• public java.util.Iterator<Map.Entry<java.lang.Object, DataflowVariable<java.lang.Object>>> iterator()

  Convenience method to play nicely with Groovy object iteration methods. The iteration restrictions of ConcurrentHashMap concerning parallel access and ConcurrentModificationException apply.

  Returns:

  iterator over the stored key:DataflowVariable value pairs

• void putAt(java.lang.Object index, java.lang.Object value)

  Binds the value to the DataflowVariable that is associated with the property "index".

  Parameters:

  index - The index to associate the value with

  value - a scalar or a DataflowVariable that may block on value access

  See Also:

  DataflowVariable.bind

• private DataflowVariable<java.lang.Object> putNewUnderLock(java.lang.Object name)

  Utility method extracted just to help JIT

  Returns:

  a DFV associated with the key

  Parameters:

  name - The key to ensure has a DFV bound to it

• public DataflowVariable<java.lang.Object> remove(java.lang.Object name)

  Removes a DFV from the map and binds it to null, if it has not been bound yet

  Returns:

  A DFV is exists, or null

  Parameters:

  name - The name of the DFV to remove.

• @java.lang.Override public void setProperty(java.lang.String property, java.lang.Object newValue)

  Binds the value to the DataflowVariable that is associated with the property "name".

  Parameters:

  newValue - a scalar or a DataflowVariable that may block on value access

  See Also:

  DataflowVariable.bind