Java example source code file (DTraceProbe.java)

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Java - Java tags/keywords

class, dtraceprobe, illegalaccessexception, internal, invocationtargetexception, method, nosuchmethodexception, object, probeskeleton, reflection, runtimeexception, string

The DTraceProbe.java Java example source code

/*
 * Copyright (c) 2008, 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.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * 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.
 */

package sun.tracing.dtrace;

import java.lang.reflect.Method;
import java.lang.reflect.InvocationTargetException;

import sun.tracing.ProbeSkeleton;

class DTraceProbe extends ProbeSkeleton {
    private Object proxy;
    private Method declared_method;
    private Method implementing_method;

    DTraceProbe(Object proxy, Method m) {
        super(m.getParameterTypes());
        this.proxy = proxy;
        this.declared_method = m;
        try {
            // The JVM will override the proxy method's implementation with
            // a version that will invoke the probe.
            this.implementing_method =  proxy.getClass().getMethod(
                m.getName(), m.getParameterTypes());
        } catch (NoSuchMethodException e) {
            throw new RuntimeException("Internal error, wrong proxy class");
        }
    }

    public boolean isEnabled() {
        return JVM.isEnabled(implementing_method);
    }

    public void uncheckedTrigger(Object[] args) {
        try {
            implementing_method.invoke(proxy, args);
        } catch (IllegalAccessException e) {
            assert false;
        } catch (InvocationTargetException e) {
            assert false;
        }
    }

    String getProbeName() {
        return DTraceProvider.getProbeName(declared_method);
    }

    String getFunctionName() {
        return DTraceProvider.getFunctionName(declared_method);
    }

    Method getMethod() {
        return implementing_method;
    }

    Class<?>[] getParameterTypes() {
        return this.parameters;
    }
}