IndexOfBenchmark

import java.util.Random;

public class IndexOfBenchmark {
    static Random rng = new Random(2017);
    static String [] paths = new String[1000];
    static final int loops = 100000;

    public static void main(String[] args) {
        for (int i = 0; i < paths.length; i++) {
            boolean odd = ((i & 1) == 1);
            paths[i] = odd ? randomName() : randomNameWithSlash();
        }
        int acc = 0;
        for (int i = 0; i < loops; i++) {
            acc += StringContains();
        }
        for (int i = 0; i < loops; i++) {
            acc += StringIndexOfChar();
        }
        for (int i = 0; i < loops; i++) {
            acc += StringIndexOfString();
        }
        System.out.println("Contains warmup: "+acc);

        for (int t = 0; t < 10; t++) {
            acc = 0;
            long start = System.nanoTime();
            for (int i = 0; i < loops; i++) {
                acc += StringContains();
            }
            long dur = System.nanoTime()-start;
            System.out.println("String.contains(String): "+dur+"ns   acc="+acc);

            acc = 0;
            start = System.nanoTime();
            for (int i = 0; i < loops; i++) {
                acc += StringIndexOfChar();
            }
            dur = System.nanoTime()-start;
            System.out.println("String.indexOf(char):    "+dur+"ns   acc="+acc);

            acc = 0;
            start = System.nanoTime();
            for (int i = 0; i < loops; i++) {
                acc += StringIndexOfString();
            }
            dur = System.nanoTime()-start;
            System.out.println("String.indexOf(String):  "+dur+"ns   acc="+acc);

            System.out.println("---------------------------");
        }

    }

    private static int StringContains() {
        int acc = 0;
        for (String s : paths) {
            if (s.contains("/")) {
                acc++;
            }
        }
        return acc;
    }

    private static int StringIndexOfChar() {
        int acc = 0;
        for (String s : paths) {
            if (s.indexOf('/') > -1)
                acc++;
        }
        return acc;
    }
    private static int StringIndexOfString() {
        int acc = 0;
        for (String s : paths) {
            if (s.indexOf("/") > -1)
                acc++;
        }
        return acc;
    }


    private static String randomName() {
        StringBuilder sb = new StringBuilder(32);
        int len = 10 + rng.nextInt(22);
        for (int i = 0; i < len; i++) {
            sb.append((char)('a'+rng.nextInt(26)));
        }
        return sb.toString();
    }
    private static String randomNameWithSlash() {
        StringBuilder sb = new StringBuilder(32);
        int len1 = 5 + rng.nextInt(11);
        int len2 = 4 + rng.nextInt(11);
        for (int i = 0; i < len1; i++) {
            sb.append((char)('a'+rng.nextInt(26)));
        }
        sb.append('/');
        for (int i = 0; i < len2; i++) {
            sb.append((char)('a'+rng.nextInt(26)));
        }
        return sb.toString();
    }
}