/*

 * Copyright (c) 1998, 2010, 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.

 *

 */

#ifndef SHARE_VM_UTILITIES_HISTOGRAM_HPP

#define SHARE_VM_UTILITIES_HISTOGRAM_HPP

#include "memory/allocation.hpp"

#include "runtime/os.hpp"

#include "utilities/growableArray.hpp"

#ifdef TARGET_OS_FAMILY_linux

# include "os_linux.inline.hpp"

#endif

#ifdef TARGET_OS_FAMILY_solaris

# include "os_solaris.inline.hpp"

#endif

#ifdef TARGET_OS_FAMILY_windows

# include "os_windows.inline.hpp"

#endif

// This class provides a framework for collecting various statistics.

// The current implementation is oriented towards counting invocations

// of various types, but that can be easily changed.

//

// To use it, you need to declare a Histogram*, and a subtype of

// HistogramElement:

//

//  HistogramElement* MyHistogram;

//

//  class MyHistogramElement : public HistogramElement {

//    public:

//      MyHistogramElement(char* name);

//  };

//

//  MyHistogramElement::MyHistogramElement(char* elementName) {

//    _name = elementName;

//

//    if(MyHistogram == NULL)

//      MyHistogram = new Histogram("My Call Counts",100);

//

//    MyHistogram->add_element(this);

//  }

//

//  #define MyCountWrapper(arg) static MyHistogramElement* e = new MyHistogramElement(arg); e->increment_count()

//

// This gives you a simple way to count invocations of specfic functions:

//

// void a_function_that_is_being_counted() {

//   MyCountWrapper("FunctionName");

//   ...

// }

//

// To print the results, invoke print() on your Histogram*.

#ifdef ASSERT

class HistogramElement : public CHeapObj {

 protected:

  jint _count;

  const char* _name;

 public:

  HistogramElement();

  virtual int count();

  virtual const char* name();

  virtual void increment_count();

  void print_on(outputStream* st) const;

  virtual int compare(HistogramElement* e1,HistogramElement* e2);

};

class Histogram : public CHeapObj {

 protected:

  GrowableArray<HistogramElement*>* _elements;

  GrowableArray<HistogramElement*>* elements() { return _elements; }

  const char* _title;

  const char* title() { return _title; }

  static int sort_helper(HistogramElement** e1,HistogramElement** e2);

  virtual void print_header(outputStream* st);

  virtual void print_elements(outputStream* st);

 public:

  Histogram(const char* title,int estimatedSize);

  virtual void add_element(HistogramElement* element);

  void print_on(outputStream* st) const;

};

#endif

#endif // SHARE_VM_UTILITIES_HISTOGRAM_HPP