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      1 /*
      2  * Copyright (C) 2018 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 package android.util;
     17 
     18 import com.android.internal.util.FastPrintWriter;
     19 
     20 import com.google.caliper.AfterExperiment;
     21 import com.google.caliper.BeforeExperiment;
     22 
     23 import java.io.IOException;
     24 import java.io.OutputStream;
     25 import java.util.ArrayList;
     26 import java.util.Arrays;
     27 import java.util.Comparator;
     28 import java.util.List;
     29 import java.util.Random;
     30 import java.util.stream.Collectors;
     31 
     32 public class StreamsBenchmark {
     33     private OutputStream dummy = new OutputStream() {
     34         @Override
     35         public void write(int b) throws IOException {
     36         }
     37 
     38         @Override
     39         public void write(byte b[], int off, int len) throws IOException {
     40         }
     41     };
     42 
     43     private SparseIntArray calls;
     44 
     45     @BeforeExperiment
     46     protected void setUp() {
     47         calls = new SparseIntArray();
     48         final Random r = new Random(1);
     49         for (int i = 0; i < 100; i++) {
     50             calls.put(i, r.nextInt(Integer.MAX_VALUE));
     51         }
     52     }
     53 
     54     @AfterExperiment
     55     protected void tearDown() {
     56         calls = null;
     57     }
     58 
     59     public void timeDirect(int reps) {
     60         for (int i = 0; i < reps; i++) {
     61             final int N = calls.size();
     62             final long[] values = new long[N];
     63             for (int j = 0; j < N; j++) {
     64                 values[j] = ((long) calls.valueAt(j) << 32) | calls.keyAt(j);
     65             }
     66             Arrays.sort(values);
     67 
     68             final FastPrintWriter pw = new FastPrintWriter(dummy);
     69             pw.println("Top openSession callers (uid=count):");
     70             final int end = Math.max(0, N - 20);
     71             for (int j = N - 1; j >= end; j--) {
     72                 final int uid = (int) (values[j] & 0xffffffff);
     73                 final int count = (int) (values[j] >> 32);
     74                 pw.print(uid);
     75                 pw.print("=");
     76                 pw.println(count);
     77             }
     78             pw.println();
     79             pw.flush();
     80         }
     81     }
     82 
     83     public void timeStreams(int reps) {
     84         for (int i = 0; i < reps; i++) {
     85             List<Pair<Integer, Integer>> callsList =
     86                     getOpenSessionCallsList(calls).stream().sorted(
     87                             Comparator.comparing(
     88                                     (Pair<Integer, Integer> pair) -> pair.second).reversed())
     89                     .limit(20)
     90                     .collect(Collectors.toList());
     91 
     92             final FastPrintWriter pw = new FastPrintWriter(dummy);
     93             pw.println("Top openSession callers (uid=count):");
     94             for (Pair<Integer, Integer> uidCalls : callsList) {
     95                 pw.print(uidCalls.first);
     96                 pw.print("=");
     97                 pw.println(uidCalls.second);
     98             }
     99             pw.println();
    100             pw.flush();
    101         }
    102     }
    103 
    104     private static List<Pair<Integer, Integer>> getOpenSessionCallsList(
    105             SparseIntArray openSessionCalls) {
    106         ArrayList<Pair<Integer, Integer>> list = new ArrayList<>(openSessionCalls.size());
    107         for (int i=0; i<openSessionCalls.size(); i++) {
    108             final int uid = openSessionCalls.keyAt(i);
    109             list.add(new Pair<>(uid, openSessionCalls.get(uid)));
    110         }
    111 
    112         return list;
    113     }
    114 }
    115