Package com.tangosol.coherence.servlet

Class AttributeHolder

java.lang.Object
com.tangosol.util.Base
com.tangosol.coherence.servlet.AttributeHolder
All Implemented Interfaces:
Externalizable, Serializable
Direct Known Subclasses:
OptimizedHolder
public class AttributeHolder extends Base implements Externalizable
An immutable object to hold attribute values and related information.
See Also:

  • Constructor Details

    • AttributeHolder

      public AttributeHolder()
      Default constructor is required for deserialization purposes.

    • AttributeHolder

      public AttributeHolder(AbstractHttpSessionModel model)

    • AttributeHolder

      public AttributeHolder(String sName, Object oValue, AbstractHttpSessionModel model)
      Construct an AttributeHolder for a value.
      Parameters:
      sName - the attribute name
      oValue - the value of the attribute; not null
      model - the http session model

  • Method Details

    • getModel

      public AbstractHttpSessionModel getModel()
      Return the AbstractHttpSessionModel to which this AttributeHolder belongs.
      Returns:
      the parent AbstractHttpSessionModel

    • setModel

      protected void setModel(AbstractHttpSessionModel model)

    • getName

      public String getName()
      Determine the name of the attribute.
      Returns:
      the attribute name managed by this holder

    • getValue

      public Object getValue()
      Obtain the object form of the value.
      Returns:
      the object form of the value

    • isActivationListener

      public boolean isActivationListener()
      Determine if the value is an object that implements the HttpSessionActivationListener interface.
      Returns:
      true if the value implements HttpSessionActivationListener

    • isBindingListener

      public boolean isBindingListener()
      Determine if the value is an object that implements the HttpSessionBindingListener interface.
      Returns:
      true if the value implements HttpSessionBindingListener

    • onBound

      public void onBound(AttributeHolder holderOrig)
      Called when the attribute is bound.
      Parameters:
      holderOrig - the holder that this new bound holder is replacing, if any, otherwise null

    • onUnbound

      public void onUnbound(boolean fReplaced, boolean fAll)
      Called when the attribute is unbound.
      Parameters:
      fReplaced - set to true of this is the result of a bind operation (so the holder is being replaced)
      fAll - true if this method is called within the context of an AbstractHttpSessionModel.unbind() call

    • isLocal

      public boolean isLocal()
      If a session distribution controller is used, and if the session is not local (is distributed), then this property specifies whether or not this specific attribute is managed locally.
      Returns:
      true iff the attribute is managed locally

    • setLocal

      protected void setLocal(boolean fLocal)
      Specify whether or not this attribute is managed locally.

      Note: an attribute could change from local to distributed if and only if a session distribution controller is used and the session is distributed. It could change from distributed to local only as a result of serialization failure when the attribute preservation feature is enabled.

      Parameters:
      fLocal - true iff the attribute is managed locally

    • flush

      protected void flush() throws IOException
      Called to flush the value to its data storage.
      Throws:
      IOException - on I/O error

    • getInternalValue

      protected Object getInternalValue()
      Obtain the internally managed object value.
      Returns:
      the cached object form of the value, or null if it has not been lazily deserialized

    • setInternalValue

      protected void setInternalValue(Object oValue)
      Store the internally managed object value.
      Parameters:
      oValue - the object form of the value

    • isSuspect

      protected boolean isSuspect()
      Determine if the value needs to be serialized because it was never serialized or because it could have changed.
      Returns:
      true if the holder's value has been accessed and is mutable

    • isSuspect

      protected boolean isSuspect(Object oValue)
      Determine if the value needs to be marked as suspect because suspect attribute handling is enabled and it is not known to be immutable
      Parameters:
      oValue - the object which may be suspect
      Returns:
      true if the object is deemed suspect

    • setSuspect

      protected void setSuspect(boolean fSuspect)
      Toggle the suspect flag for the value. Method provided to enable effective subclassing.
      Parameters:
      fSuspect - true if suspect, false otherwise

    • prepareWrite

      protected void prepareWrite() throws IOException
      Called to test serialization; if the holder cannot serialize its value, it should throw an IOException at this point. Note that this method should only be called as part of the "write" processing for the model, as the holder will expect an immediate follow-up call to actually write itself out.
      Throws:
      IOException - if the holder cannot serialize its value

    • isEnableSuspectAttributes

      protected boolean isEnableSuspectAttributes()
      Determine if suspect attributes need special treatment.
      Returns:
      true iff suspect attributes need special treatment
      See Also:

    • readExternal

      public void readExternal(ObjectInput in) throws IOException
      The object implements the readExternal method to restore its contents by calling the methods of DataInput for primitive types and readObject for objects, strings and arrays. The readExternal method must read the values in the same sequence and with the same types as were written by writeExternal.
      Specified by:
      readExternal in interface Externalizable
      Parameters:
      in - the stream to read data from in order to restore the object
      Throws:
      IOException - if an I/O exception occurs

    • writeExternal

      public void writeExternal(ObjectOutput out) throws IOException
      The object implements the writeExternal method to save its contents by calling the methods of DataOutput for its primitive values or calling the writeObject method of ObjectOutput for objects, strings, and arrays.
      Specified by:
      writeExternal in interface Externalizable
      Parameters:
      out - the stream to write the object to
      Throws:
      IOException - if an I/O exception occurs

    • readExternal

      public void readExternal(DataInput in) throws IOException
      Helper to read the object state from a stream.
      Parameters:
      in - the stream to read data from in order to restore the object
      Throws:
      IOException - if an I/O exception occurs

    • writeExternal

      public void writeExternal(DataOutput out) throws IOException
      Helper to write the object state to a stream.
      Parameters:
      out - the stream to write the object to
      Throws:
      IOException - if an I/O exception occurs