Java in a Nutshell, 5th Edition

Name

Package javax.security.auth.callback

Synopsis

This package defines a mechanism that allows the low-level code of a javax.security.auth.spi.LoginModule to interact with the end-user of an application to obtain a username, password, or other authentication-related information. The LoginModule sends messages and requests for information in the form of objects that implement the Callback interface. An application that wants to authenticate a user provides (via a javax.security.auth.login.LoginContext) a CallbackHandler object to convert these Callback objects into text or GUI-based interactions with the user. An application that want to provide a customized login interface must implement its own CallbackHandler. The CallbackHandler API consists of only a single method, but the implementation of that method can require a substantial amount of code. See the various Callback classes for directions on how a CallbackHandler should handle them.

Sun’s J2SE SDK for Java 1.4 ships with two implementations of CallbackHandler, both in the package com.sun.security.auth.callback. Although these classes are not guaranteed to exist in all distributions, text-based applications may use the TextCallbackHandler, and GUI-based applications may use the DialogCallbackHandler. Programmers wanting to write a custom CallbackHandler may also find it useful to study the source code of these two existing handlers.

Interfaces

public interface Callback;
public interface CallbackHandler;

Classes

public class ChoiceCallback ...