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package com.sun.net.httpserver;

import java.util.Base64;


BasicAuthenticator provides an implementation of HTTP Basic authentication. It is an abstract class and must be extended to provide an implementation of checkCredentials(String, String) which is called to verify each incoming request. 
/**
 * BasicAuthenticator provides an implementation of HTTP Basic
 * authentication. It is an abstract class and must be extended
 * to provide an implementation of {@link #checkCredentials(String,String)}
 * which is called to verify each incoming request.
 */
public abstract class BasicAuthenticator extends Authenticator {

    protected String realm;

    
Creates a BasicAuthenticator for the given HTTP realm

Params:
  • realm – The HTTP Basic authentication realm
Throws:
/**
     * Creates a BasicAuthenticator for the given HTTP realm
     * @param realm The HTTP Basic authentication realm
     * @throws NullPointerException if the realm is an empty string
     */
    public BasicAuthenticator (String realm) {
        this.realm = realm;
    }

    
returns the realm this BasicAuthenticator was created with

Returns:the authenticator's realm string.
/**
     * returns the realm this BasicAuthenticator was created with
     * @return the authenticator's realm string.
     */
    public String getRealm () {
        return realm;
    }

    public Result authenticate (HttpExchange t)
    {
        Headers rmap = t.getRequestHeaders();
        /*
         * look for auth token
         */
        String auth = rmap.getFirst ("Authorization");
        if (auth == null) {
            Headers map = t.getResponseHeaders();
            map.set ("WWW-Authenticate", "Basic realm=" + "\""+realm+"\"");
            return new Authenticator.Retry (401);
        }
        int sp = auth.indexOf (' ');
        if (sp == -1 || !auth.substring(0, sp).equals ("Basic")) {
            return new Authenticator.Failure (401);
        }
        byte[] b = Base64.getDecoder().decode(auth.substring(sp+1));
        String userpass = new String (b);
        int colon = userpass.indexOf (':');
        String uname = userpass.substring (0, colon);
        String pass = userpass.substring (colon+1);

        if (checkCredentials (uname, pass)) {
            return new Authenticator.Success (
                new HttpPrincipal (
                    uname, realm
                )
            );
        } else {
            /* reject the request again with 401 */

            Headers map = t.getResponseHeaders();
            map.set ("WWW-Authenticate", "Basic realm=" + "\""+realm+"\"");
            return new Authenticator.Failure(401);
        }
    }

    
called for each incoming request to verify the
given name and password in the context of this
Authenticator's realm. Any caching of credentials
must be done by the implementation of this method

Params:
  • username – the username from the request
  • password – the password from the request
Returns:true if the credentials are valid,
   false otherwise.
/**
     * called for each incoming request to verify the
     * given name and password in the context of this
     * Authenticator's realm. Any caching of credentials
     * must be done by the implementation of this method
     * @param username the username from the request
     * @param password the password from the request
     * @return <code>true</code> if the credentials are valid,
     *    <code>false</code> otherwise.
     */
    public abstract boolean checkCredentials (String username, String password);
}