Core Java™ Data Objects

2.2. JDK Binary Serialization

Serialization is the basic persistence support that is built into the Java language. It is called serialization because the objects are written or read sequentially as a series of bytes. An object is serializable if its class implements the serializable interface and all its non-transient members are as well serializable. When an object is serialized, the default algorithm traverses the closure of the object graph and writes all reachable objects to a stream. If a member of a class is tagged transient, the default algorithm skips this field.

When the stream is read back, the equivalent object graph is rebuilt, keeping transient members initialized to their null values. By tagging a field as transient, its referenced ...