谁能告诉我关于java序列化的原理以及如何实现？
------最佳解决方案--------------------------------------------------------
/**
* Serializability of a class is enabled by the class implementing the
* java.io.Serializable interface. Classes that do not implement this
* interface will not have any of their state serialized or
* deserialized. All subtypes of a serializable class are themselves
* serializable. The serialization interface has no methods or fields
* and serves only to identify the semantics of being serializable. <p>
*
* To allow subtypes of non-serializable classes to be serialized, the
* subtype may assume responsibility for saving and restoring the
* state of the supertype's public, protected, and (if accessible)
* package fields. The subtype may assume this responsibility only if
* the class it extends has an accessible no-arg constructor to
* initialize the class's state. It is an error to declare a class
* Serializable if this is not the case. The error will be detected at
* runtime. <p>
*
* During deserialization, the fields of non-serializable classes will
* be initialized using the public or protected no-arg constructor of
* the class. A no-arg constructor must be accessible to the subclass
* that is serializable. The fields of serializable subclasses will
* be restored from the stream. <p>
*
* When traversing a graph, an object may be encountered that does not
* support the Serializable interface. In this case the
* NotSerializableException will be thrown and will identify the class
* of the non-serializable object. <p>
*
* Classes that require special handling during the serialization and
* deserialization process must implement special methods with these exact
* signatures: <p>
*
* <PRE>
* private void writeObject(java.io.ObjectOutputStream out)
* throws IOException
* private void readObject(java.io.ObjectInputStream in)
* throws IOException, ClassNotFoundException;
* private void readObjectNoData()
* throws ObjectStreamException;
* </PRE>
*
* <p>The writeObject method is responsible for writing the state of the
* object for its particular class so that the corresponding