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      1 /*
      2  * Copyright (C) 2008 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 import java.io.Serializable;
     18 import java.util.*;
     19 
     20 /**
     21  * A loaded class.
     22  */
     23 class LoadedClass implements Serializable, Comparable<LoadedClass> {
     24 
     25     private static final long serialVersionUID = 0;
     26 
     27     /** Class name. */
     28     final String name;
     29 
     30     /** Load operations. */
     31     final List<Operation> loads = new ArrayList<Operation>();
     32 
     33     /** Static initialization operations. */
     34     final List<Operation> initializations = new ArrayList<Operation>();
     35 
     36     /** Memory usage gathered by loading only this class in its own VM. */
     37     MemoryUsage memoryUsage = MemoryUsage.NOT_AVAILABLE;
     38 
     39     /**
     40      * Whether or not this class was loaded in the system class loader.
     41      */
     42     final boolean systemClass;
     43 
     44     /** Whether or not this class will be preloaded. */
     45     boolean preloaded;
     46 
     47     /** Constructs a new class. */
     48     LoadedClass(String name, boolean systemClass) {
     49         this.name = name;
     50         this.systemClass = systemClass;
     51     }
     52 
     53     void measureMemoryUsage() {
     54         this.memoryUsage = MemoryUsage.forClass(name);
     55     }
     56 
     57     int mlt = -1;
     58 
     59     /** Median time to load this class. */
     60     int medianLoadTimeMicros() {
     61         if (mlt != -1) {
     62             return mlt;
     63         }
     64 
     65         return mlt = calculateMedian(loads);
     66     }
     67 
     68     int mit = -1;
     69 
     70     /** Median time to initialize this class. */
     71     int medianInitTimeMicros() {
     72         if (mit != -1) {
     73             return mit;
     74         }
     75 
     76         return mit = calculateMedian(initializations);
     77     }
     78 
     79     int medianTimeMicros() {
     80         return medianInitTimeMicros() + medianLoadTimeMicros();
     81     }
     82 
     83     /** Calculates the median duration for a list of operations. */
     84     private static int calculateMedian(List<Operation> operations) {
     85         int size = operations.size();
     86         if (size == 0) {
     87             return 0;
     88         }
     89 
     90         int[] times = new int[size];
     91         for (int i = 0; i < size; i++) {
     92             times[i] = operations.get(i).exclusiveTimeMicros();
     93         }
     94 
     95         Arrays.sort(times);
     96         int middle = size / 2;
     97         if (size % 2 == 1) {
     98             // Odd
     99             return times[middle];
    100         } else {
    101             // Even -- average the two.
    102             return (times[middle - 1] + times[middle]) / 2;
    103         }
    104     }
    105 
    106     /** Returns names of processes that loaded this class. */
    107     Set<String> processNames() {
    108         Set<String> names = new HashSet<String>();
    109         addProcessNames(loads, names);
    110         addProcessNames(initializations, names);
    111         return names;
    112     }
    113 
    114     private void addProcessNames(List<Operation> ops, Set<String> names) {
    115         for (Operation operation : ops) {
    116             if (operation.process.fromZygote()) {
    117                 names.add(operation.process.name);
    118             }
    119         }
    120     }
    121 
    122     public int compareTo(LoadedClass o) {
    123         return name.compareTo(o.name);
    124     }
    125 
    126     @Override
    127     public String toString() {
    128         return name;
    129     }
    130 }
    131