Java example source code file (NoInstalledProviders.java)

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Java - Java tags/keywords

exception, noinstalledproviders, provider, providerssnapshot, security, string

The NoInstalledProviders.java Java example source code

/*
 * Copyright (c) 1999, 2011, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code 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
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

/*
 * @test
 * @bug 4273454 7054918 7052537
 * @library ../testlibrary
 * @summary Make sure getProviders(filter) doesn't throw NPE
 * @run main/othervm NoInstalledProviders
 */

import java.security.*;

public class NoInstalledProviders {

    public static void main(String[] args) throws Exception {
        ProvidersSnapshot snapshot = ProvidersSnapshot.create();
        try {
            main0(args);
        } finally {
            snapshot.restore();
        }
    }

    public static void main0(String[] args) throws Exception {

        Provider[] provs = Security.getProviders();
        // make sure there are no providers in the system
        for(int i = 0; i < provs.length; i++ ) {
            Security.removeProvider( provs[i].getName());
        }

        String filter = "Signature.SHA1withDSA";

        provs = Security.getProviders(filter);
    }
}