1 /*

     2  * Copyright (c) 2008, Oracle and/or its affiliates. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.  Oracle designates this

     8  * particular file as subject to the "Classpath" exception as provided

     9  * by Oracle in the LICENSE file that accompanied this code.

    10  *

    11  * This code is distributed in the hope that it will be useful, but WITHOUT

    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    14  * version 2 for more details (a copy is included in the LICENSE file that

    15  * accompanied this code).

    16  *

    17  * You should have received a copy of the GNU General Public License version

    18  * 2 along with this work; if not, write to the Free Software Foundation,

    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    20  *

    21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    22  * or visit www.oracle.com if you need additional information or have any

    23  * questions.

    24  */

    25 

    26 package sun.tracing;

    27 

    28 import java.lang.reflect.Method;

    29 

    30 import com.sun.tracing.ProviderFactory;

    31 import com.sun.tracing.Provider;

    32 

    33 /**

    34  * Factory class to create tracing Providers.

    35  *

    36  * This factory will create tracing instances that do nothing.

    37  * It is used when no tracing is desired, but Provider instances still

    38  * must be generated so that tracing calls in the application continue to

    39  * run.

    40  *

    41  * @since 1.7

    42  */

    43 public class NullProviderFactory extends ProviderFactory {

    44 

    45     /**

    46      * Creates and returns a Null provider.

    47      *

    48      * See comments at {@code ProviderSkeleton.createProvider()} for more

    49      * details.

    50      *

    51      * @return a provider whose probe trigger are no-ops.

    52      */

    53     public <T extends Provider> T createProvider(Class<T> cls) {

    54         NullProvider provider = new NullProvider(cls);

    55         provider.init();

    56         return provider.newProxyInstance();

    57     }

    58 }

    59 

    60 class NullProvider extends ProviderSkeleton {

    61 

    62     NullProvider(Class<? extends Provider> type) {

    63         super(type);

    64     }

    65 

    66     protected ProbeSkeleton createProbe(Method m) {

    67         return new NullProbe(m.getParameterTypes());

    68     }

    69 }

    70 

    71 class NullProbe extends ProbeSkeleton {

    72 

    73     public NullProbe(Class<?>[] parameters) {

    74         super(parameters);

    75     }

    76 

    77     public boolean isEnabled() {

    78         return false;

    79     }

    80 

    81     public void uncheckedTrigger(Object[] args) {

    82     }

    83 }

    84