From 554fd8c5195424bdbcabf5de30fdc183aba391bd Mon Sep 17 00:00:00 2001 From: upstream source tree Date: Sun, 15 Mar 2015 20:14:05 -0400 Subject: obtained gcc-4.6.4.tar.bz2 from upstream website; verified gcc-4.6.4.tar.bz2.sig; imported gcc-4.6.4 source tree from verified upstream tarball. downloading a git-generated archive based on the 'upstream' tag should provide you with a source tree that is binary identical to the one extracted from the above tarball. if you have obtained the source via the command 'git clone', however, do note that line-endings of files in your working directory might differ from line-endings of the respective files in the upstream repository. --- .../security/auth/callback/CallbackHandler.java | 155 +++++++++++++++++++++ 1 file changed, 155 insertions(+) create mode 100644 libjava/classpath/javax/security/auth/callback/CallbackHandler.java (limited to 'libjava/classpath/javax/security/auth/callback/CallbackHandler.java') diff --git a/libjava/classpath/javax/security/auth/callback/CallbackHandler.java b/libjava/classpath/javax/security/auth/callback/CallbackHandler.java new file mode 100644 index 000000000..8d22943ca --- /dev/null +++ b/libjava/classpath/javax/security/auth/callback/CallbackHandler.java @@ -0,0 +1,155 @@ +/* CallbackHandler.java -- base interface for callback handlers. + Copyright (C) 2003, Free Software Foundation, Inc. + +This file is part of GNU Classpath. + +GNU Classpath is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2, or (at your option) +any later version. + +GNU Classpath is distributed in the hope that it will be useful, but +WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +General Public License for more details. + +You should have received a copy of the GNU General Public License +along with GNU Classpath; see the file COPYING. If not, write to the +Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA +02110-1301 USA. + +Linking this library statically or dynamically with other modules is +making a combined work based on this library. Thus, the terms and +conditions of the GNU General Public License cover the whole +combination. + +As a special exception, the copyright holders of this library give you +permission to link this library with independent modules to produce an +executable, regardless of the license terms of these independent +modules, and to copy and distribute the resulting executable under +terms of your choice, provided that you also meet, for each linked +independent module, the terms and conditions of the license of that +module. An independent module is a module which is not derived from +or based on this library. If you modify this library, you may extend +this exception to your version of the library, but you are not +obligated to do so. If you do not wish to do so, delete this +exception statement from your version. */ + + +package javax.security.auth.callback; + +import java.io.IOException; + +/** + *

An application implements a CallbackHandler and passes it to + * underlying security services so that they may interact with the application + * to retrieve specific authentication data, such as usernames and passwords, or + * to display certain information, such as error and warning messages.

+ * + *

CallbackHandlers are implemented in an application-dependent + * fashion. For example, implementations for an application with a graphical + * user interface (GUI) may pop up windows to prompt for requested information + * or to display error messages. An implementation may also choose to obtain + * requested information from an alternate source without asking the end user.

+ * + *

Underlying security services make requests for different types of + * information by passing individual Callbacks to the CallbackHandler. + * The CallbackHandler implementation decides how to retrieve and + * display information depending on the {@link Callback}s passed to it. For + * example, if the underlying service needs a username and password to + * authenticate a user, it uses a {@link NameCallback} and + * {@link PasswordCallback}. The CallbackHandler can then choose + * to prompt for a username and password serially, or to prompt for both in a + * single window.

+ * + *

A default CallbackHandler class implementation may be + * specified in the auth.login.defaultCallbackHandler security + * property. The security property can be set in the Java security properties + * file located in the file named + * <JAVA_HOME>/lib/security/java.security, where + * <JAVA_HOME> refers to the directory where the SDK was + * installed.

+ * + *

If the security property is set to the fully qualified name of a + * CallbackHandler implementation class, then a + * LoginContextwill load the specified CallbackHandler + * and pass it to the underlying LoginModules. The + * LoginContext only loads the default handler if one was not + * provided.

+ * + *

All default handler implementations must provide a public zero-argument + * constructor.

+ * + */ +public interface CallbackHandler +{ + + /** + *

Retrieve or display the information requested in the provided + * {@link Callback}s.

+ * + *

The handle() method implementation checks the instance(s) + * of the {@link Callback} object(s) passed in to retrieve or display the + * requested information. The following example is provided to help + * demonstrate what an handle() method implementation might look + * like. This example code is for guidance only. Many details, including + * proper error handling, are left out for simplicity.

+ * + * 
+   *public void handle(Callback[] callbacks)
+   *throws IOException, UnsupportedCallbackException {
+   *   for (int i = 0; i < callbacks.length; i++) {
+   *      if (callbacks[i] instanceof TextOutputCallback) {
+   *         // display the message according to the specified type
+   *         TextOutputCallback toc = (TextOutputCallback)callbacks[i];
+   *         switch (toc.getMessageType()) {
+   *         case TextOutputCallback.INFORMATION:
+   *            System.out.println(toc.getMessage());
+   *            break;
+   *         case TextOutputCallback.ERROR:
+   *            System.out.println("ERROR: " + toc.getMessage());
+   *            break;
+   *         case TextOutputCallback.WARNING:
+   *            System.out.println("WARNING: " + toc.getMessage());
+   *            break;
+   *         default:
+   *            throw new IOException("Unsupported message type: "
+   *                  + toc.getMessageType());
+   *         }
+   *      } else if (callbacks[i] instanceof NameCallback) {
+   *         // prompt the user for a username
+   *         NameCallback nc = (NameCallback)callbacks[i];
+   *         // ignore the provided defaultName
+   *         System.err.print(nc.getPrompt());
+   *         System.err.flush();
+   *         nc.setName((new BufferedReader(
+   *               new InputStreamReader(System.in))).readLine());
+   *      } else if (callbacks[i] instanceof PasswordCallback) {
+   *         // prompt the user for sensitive information
+   *         PasswordCallback pc = (PasswordCallback)callbacks[i];
+   *         System.err.print(pc.getPrompt());
+   *         System.err.flush();
+   *         pc.setPassword(readPassword(System.in));
+   *      } else {
+   *         throw new UnsupportedCallbackException(
+   *               callbacks[i], "Unrecognized Callback");
+   *      }
+   *   }
+   *}
+   *
+   * // Reads user password from given input stream.
+   *private char[] readPassword(InputStream in) throws IOException {
+   *   // insert code to read a user password from the input stream
+   *}
+   *
+ * + * @param callbacks an array of {@link Callback} objects provided by an + * underlying security service which contains the information requested to + * be retrieved or displayed. + * @throws IOException if an input or output error occurs. + * @throws UnsupportedCallbackException if the implementation of this method + * does not support one or more of the Callbacks specified in the + * callbacks parameter. + */ + void handle(Callback[] callbacks) throws IOException, UnsupportedCallbackException; +} -- cgit v1.2.3