Package jadex.commons.beans

Class Encoder

  • Direct Known Subclasses:
    XMLEncoder
    public class Encoder
extends java.lang.Object
    The Encoder, together with PersistenceDelegate s, can encode an object into a series of java statements. By executing these statements, a new object can be created and it will has the same state as the original object which has been passed to the encoder. Here "has the same state" means the two objects are indistinguishable from their public API. Encoder and PersistenceDelegate s do this by creating copies of the input object and all objects it references. The copy process continues recursively util every object in the object graph has its new copy and the new version has the same state as the old version. All statements used to create those new objects and executed on them during the process form the result of encoding.

    • Constructor Detail

      • Encoder

        public Encoder()
        Construct a new encoder.

    • Method Detail

      • get

        public java.lang.Object get​(java.lang.Object old)
        Gets the new copy of the given old object.
        Parameters:
        old - an old object
        Returns:
        the new copy of the given old object, or null if there is not one.

      • getExceptionListener

        public ExceptionListener getExceptionListener()
        Returns the exception listener of this encoder.
        Returns:
        the exception listener of this encoder

      • getPersistenceDelegate

        public PersistenceDelegate getPersistenceDelegate​(java.lang.Class<?> type)
        Returns a PersistenceDelegate for the given class type. PersistenceDelegate is determined as following: PersistenceDelegate has been registered by calling setPersistenceDelegate for the given type, it is returned.PersistenceDelegate for array types is returned.PersistenceDelegate for proxy classes is returned.Introspector is used to check the bean descriptor value "persistenceDelegate". If one is set, it is returned.DefaultPersistenceDelegate is returned.
        Parameters:
        type - a class type
        Returns:
        a PersistenceDelegate for the given class type

      • remove

        public java.lang.Object remove​(java.lang.Object old)
        Remvoe the existing new copy of the given old object.
        Parameters:
        old - an old object
        Returns:
        the removed new version of the old object, or null if there is not one

      • setExceptionListener

        public void setExceptionListener​(ExceptionListener listener)
        Sets the exception listener of this encoder.
        Parameters:
        listener - the exception listener to set

      • setPersistenceDelegate

        public void setPersistenceDelegate​(java.lang.Class<?> type,
                                   PersistenceDelegate delegate)
        Register the PersistenceDelegate of the specified type.
        Parameters:
        type -
        delegate -

      • writeExpression

        public void writeExpression​(Expression oldExp)
        Write an expression of old objects. writeObject() is called to create the new version. writeObject() with the old return value, so that more statements will be executed on its new version to change it into the same state as the old value.
        Parameters:
        oldExp - the expression to write. The target, arguments, and return value of the expression are all old objects.

      • writeObject

        protected void writeObject​(java.lang.Object o)
        Encode the given object into a series of statements and expressions. PersistenceDelegate responsible for the object's class, and delegate the call to it.
        Parameters:
        o - the object to encode

      • writeStatement

        public void writeStatement​(Statement oldStat)
        Write a statement of old objects. writeObject() is called to create one.
        Parameters:
        oldStat - a statement of old objects