Java IO.pdf - Nguyen Dang Binh

Example 11.6. Person
import java.util.*;
import java.io.*;
public class Person implements Serializable, ObjectInputValidation {
}
static Hashtable thePeople = new Hashtable();
String name;
String ss;
public Person(String name, String ss) {
}
this.name = name;
this.ss = ss;
thePeople.put(ss, name);
private void readObject(ObjectInputStream in)
throws IOException, ClassNotFoundException {
}
in.registerValidation(this, 5);
in.defaultReadObject();
public void validateObject() throws InvalidObjectException {
}
if (thePeople.containsKey(this.ss)) {
throw new InvalidObjectException(this.name + " already exists");
}
else {
thePeople.put(this.ss, this.name);
}
public String toString() {
return this.name + "\t" + this.ss;
}
11.12 Sealed Objects
Java I/O
The JCE standard extension to Java 2, discussed in the last chapter, provides a SealedObject
class that lets you encrypt objects written onto an object output stream using any available
cipher. Most of the time, I suspect, you'll either encrypt the entire object output stream by
chaining it to a cipher output stream, or you won't encrypt anything at all. However, if there's
some reason to encrypt only some of the objects you're writing to the stream, you can make
them sealed objects.
The javax.crypto.SealedObject class wraps a serializable object in an encrypted digital
lockbox. The sealed object is serializable so it can be written onto object output streams and
read from object input streams as normal. However, the object inside the sealed object can
only be deserialized by someone who knows the key.
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