| /* |
| * Copyright (c) 2001, 2012, 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 |
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| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
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| */ |
| |
| #ifndef SHARE_VM_UTILITIES_INTHISTO_HPP |
| #define SHARE_VM_UTILITIES_INTHISTO_HPP |
| |
| #include "memory/allocation.hpp" |
| #include "utilities/growableArray.hpp" |
| |
| // This class implements a simple histogram. |
| |
| // A histogram summarizes a series of "measurements", each of which is |
| // assumed (required in this implementation) to have an outcome that is a |
| // non-negative integer. The histogram efficiently maps measurement outcomes |
| // to the number of measurements had that outcome. |
| |
| // To print the results, invoke print() on your Histogram*. |
| |
| // Note: there is already an existing "Histogram" class, in file |
| // histogram.{hpp,cpp}, but to my mind that's not a histogram, it's a table |
| // mapping strings to counts. To be a histogram (IMHO) it needs to map |
| // numbers (in fact, integers) to number of occurrences of that number. |
| |
| // ysr: (i am not sure i agree with the above note.) i suspect we want to have a |
| // histogram template that will map an arbitrary type (with a defined order |
| // relation) to a count. |
| |
| |
| class IntHistogram : public CHeapObj<mtInternal> { |
| protected: |
| int _max; |
| int _tot; |
| GrowableArray<int>* _elements; |
| |
| public: |
| // Create a new, empty table. "est" is an estimate of the maximum outcome |
| // that will be added, and "max" is an outcome such that all outcomes at |
| // least that large will be bundled with it. |
| IntHistogram(int est, int max); |
| // Add a measurement with the given outcome to the sequence. |
| void add_entry(int outcome); |
| // Return the number of entries recorded so far with the given outcome. |
| int entries_for_outcome(int outcome); |
| // Return the total number of entries recorded so far. |
| int total_entries() { return _tot; } |
| // Return the number of entries recorded so far with the given outcome as |
| // a fraction of the total number recorded so far. |
| double fraction_for_outcome(int outcome) { |
| return |
| (double)entries_for_outcome(outcome)/ |
| (double)total_entries(); |
| } |
| // Print the histogram on the given output stream. |
| void print_on(outputStream* st) const; |
| }; |
| |
| #endif // SHARE_VM_UTILITIES_INTHISTO_HPP |