Package com.tangosol.util.filter

Class ValueChangeEventFilter<V,E>

java.lang.Object
com.tangosol.util.filter.ValueChangeEventFilter<V,E>
All Implemented Interfaces:
ExternalizableLite, PortableObject, Filter<MapEvent<?,V>>, Serializable
public class ValueChangeEventFilter<V,E> extends Object implements Filter<MapEvent<?,V>>, ExternalizableLite, PortableObject
Filter which evaluates the content of a MapEvent values based on the specified value extractor. This filter evaluates to true only for update events that change the value of an extracted attribute.

Example: a filter that evaluates to true if there is an update to an Employee object that changes a value of the LastName property. 

   new ValueChangeEventFilter("LastName");
Since:
Coherence 2.3
Author:
gg 2003.09.30
See Also:

  • Field Details

  • Constructor Details

    • ValueChangeEventFilter

      public ValueChangeEventFilter()
      Default constructor (necessary for the ExternalizableLite interface).

    • ValueChangeEventFilter

      public ValueChangeEventFilter(ValueExtractor<? super V,? extends E> extractor)
      Construct a ValueChangeEventFilter that evaluates MapEvent values based on the specified extractor.
      Parameters:
      extractor - ValueExtractor to extract MapEvent values

    • ValueChangeEventFilter

      public ValueChangeEventFilter(String sMethod)
      Construct a ValueChangeEventFilter that evaluates MapEvent values based on the specified method name.
      Parameters:
      sMethod - the name of the method to invoke via reflection

  • Method Details

    • evaluate

      public boolean evaluate(MapEvent<?,V> event)
      Apply the test to the input argument.
      Specified by:
      evaluate in interface Filter<V>
      Parameters:
      event - the input argument to evaluate
      Returns:
      true if the input argument matches the filter, otherwise false

    • extract

      protected E extract(V target)
      Extract value from a target object.
      Parameters:
      target - the object to extract the value from
      Returns:
      the extracted value

    • equals

      public boolean equals(Object o)
      Compare the ValueChangeEventFilter with another object to determine equality.
      Overrides:
      equals in class Object
      Returns:
      true iff this ValueChangeEventFilter and the passed object are equivalent filters

    • hashCode

      public int hashCode()
      Determine a hash value for the ValueChangeEventFilter object according to the general Object.hashCode() contract.
      Overrides:
      hashCode in class Object
      Returns:
      an integer hash value for this ValueChangeEventFilter object

    • toString

      public String toString()
      Return a human-readable description for this Filter.
      Overrides:
      toString in class Object
      Returns:
      a String description of the Filter

    • readExternal

      public void readExternal(DataInput in) throws IOException
      Description copied from interface: ExternalizableLite
      Restore the contents of this object by loading the object's state from the passed DataInput object.
      Specified by:
      readExternal in interface ExternalizableLite
      Parameters:
      in - the DataInput stream to read data from in order to restore the state of this object
      Throws:
      IOException - if an I/O exception occurs

    • writeExternal

      public void writeExternal(DataOutput out) throws IOException
      Description copied from interface: ExternalizableLite
      Save the contents of this object by storing the object's state into the passed DataOutput object.
      Specified by:
      writeExternal in interface ExternalizableLite
      Parameters:
      out - the DataOutput stream to write the state of this object to
      Throws:
      IOException - if an I/O exception occurs

    • readExternal

      public void readExternal(PofReader in) throws IOException
      Description copied from interface: PortableObject
      Restore the contents of a user type instance by reading its state using the specified PofReader object.
      Specified by:
      readExternal in interface PortableObject
      Parameters:
      in - the PofReader from which to read the object's state
      Throws:
      IOException - if an I/O error occurs

    • writeExternal

      public void writeExternal(PofWriter out) throws IOException
      Description copied from interface: PortableObject
      Save the contents of a POF user type instance by writing its state using the specified PofWriter object.
      Specified by:
      writeExternal in interface PortableObject
      Parameters:
      out - the PofWriter to which to write the object's state
      Throws:
      IOException - if an I/O error occurs