Java example source code file (Agent.java)

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Java - Java tags/keywords

agent, agentsupport, classloader, exception, instrumentation, runtimeexception, string

The Agent.java Java example source code

/*
 * Copyright (c) 2004, 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.
 */

/*
 *
 *
 * Used by BootClassPath.sh
 *
 * Loads a supporting class and tests that the class is loaded from the boot
 * class path.
 */
import java.lang.instrument.Instrumentation;

public class Agent {
    public static void premain(String options, Instrumentation ins) throws Exception {
        String bootclasspath = System.getProperty("sun.boot.class.path");
        System.out.println("bootclasspath: " + bootclasspath);

        Class c = Class.forName("AgentSupport");
        ClassLoader cl = c.getClassLoader();
        if (cl != null) {
            System.err.println("AgentSupport loaded by: " + cl);
            throw new RuntimeException("AgentSupport class not loaded by boot class loader");
        } else {
            System.out.println("AgentSupport loaded by boot class loader");
        }
    }
}