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    1   /**
    2    * Copyright (c) 2004-2011 QOS.ch
    3    * All rights reserved.
    4    *
    5    * Permission is hereby granted, free  of charge, to any person obtaining
    6    * a  copy  of this  software  and  associated  documentation files  (the
    7    * "Software"), to  deal in  the Software without  restriction, including
    8    * without limitation  the rights to  use, copy, modify,  merge, publish,
    9    * distribute,  sublicense, and/or sell  copies of  the Software,  and to
    10   * permit persons to whom the Software  is furnished to do so, subject to
    11   * the following conditions:
    12   *
    13   * The  above  copyright  notice  and  this permission  notice  shall  be
    14   * included in all copies or substantial portions of the Software.
    15   *
    16   * THE  SOFTWARE IS  PROVIDED  "AS  IS", WITHOUT  WARRANTY  OF ANY  KIND,
    17   * EXPRESS OR  IMPLIED, INCLUDING  BUT NOT LIMITED  TO THE  WARRANTIES OF
    18   * MERCHANTABILITY,    FITNESS    FOR    A   PARTICULAR    PURPOSE    AND
    19   * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
    20   * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
    21   * OF CONTRACT, TORT OR OTHERWISE,  ARISING FROM, OUT OF OR IN CONNECTION
    22   * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
    23   *
    24   */
    25  package org.slf4j.profiler;
    26
    27  /**
    28   *
    29   * This demo illustrates usage of SLF4J profilers.
    30   *
    31   * <p>
    32   * We have been given the task of generating a large number, say N,
    33   * of random integers. We need to transform that array into a smaller array
    34   * containing only prime numbers. The new array has to be sorted.
    35   *
    36   * <p>
    37   * While tackling this problem, we would like to measure the
    38   * time spent in each subtask.
    39   *
    40   * <p>
    41   * A typical output for this demo would be:
    42   <pre>
    43   + Profiler [DEMO]
    44  |-- elapsed time                       [RANDOM]     0.089  seconds.
    45  |---+ Profiler [SORT_AND_PRUNE]
    46  &nbsp;&nbsp;&nbsp;&nbsp;|-- elapsed time                         [SORT]     0.221  seconds.
    47  &nbsp;&nbsp;&nbsp;&nbsp;|-- elapsed time             [PRUNE_COMPOSITES]    11.567  seconds.
    48  &nbsp;&nbsp;&nbsp;&nbsp;|-- Subtotal                   [SORT_AND_PRUNE]    11.788  seconds.
    49  |-- elapsed time               [SORT_AND_PRUNE]    11.788  seconds.
    50  |-- Total                                [DEMO]    11.877  seconds.
    51  </pre>
    52   *
    53   * @author Ceki Gulcu
    54   */
    55  public class NestedProfilerDemo {
    56
    57      public static void main(String[] args) {
    58          // create a profiler called "DEMO"
    59          Profiler profiler = new Profiler("DEMO");
    60
    61          // register this profiler in the thread context's profiler registry
    62          ProfilerRegistry profilerRegistry = ProfilerRegistry.getThreadContextInstance();
    63          profiler.registerWith(profilerRegistry);
    64
    65          // start a stopwatch called "RANDOM"
    66          profiler.start("RANDOM");
    67          RandomIntegerArrayGenerator riaGenerator = new RandomIntegerArrayGenerator();
    68          int n = 10 * 1000;
    69          int[] randomArray = riaGenerator.generate(n);
    70
    71          // create and start a nested profiler called "SORT_AND_PRUNE"
    72          // By virtue of its parent-child relationship with the "DEMO"
    73          // profiler, and the previous registration of the parent profiler,
    74          // this nested profiler will be automatically registered
    75          // with the thread context's profiler registry
    76          profiler.startNested(SortAndPruneComposites.NESTED_PROFILER_NAME);
    77
    78          SortAndPruneComposites pruner = new SortAndPruneComposites(randomArray);
    79          pruner.sortAndPruneComposites();
    80
    81          // stop and print the "DEMO" printer
    82          profiler.stop().print();
    83      }
    84  }