changeset 50856:dd2867f9e671

8201518: add test for randomized iteration order of unmodifiable Set and Map Reviewed-by: plevart
author smarks
date Fri, 25 May 2018 11:18:22 -0700
parents 697b49a04e19
children 737a17045ffe
files test/jdk/java/util/Collection/RandomizedIteration.java
diffstat 1 files changed, 206 insertions(+), 0 deletions(-) [+]
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/jdk/java/util/Collection/RandomizedIteration.java	Fri May 25 11:18:22 2018 -0700
@@ -0,0 +1,206 @@
+/*
+ * Copyright (c) 2018, 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.
+ */
+
+/*
+ * @test
+ * @bug     8201518
+ * @key     randomness
+ * @summary Ensure that randomized iteration order of unmodifiable sets
+ *          and maps is actually randomized. Must be run othervm so that
+ *          the per-VM-instance salt value differs.
+ * @run main/othervm RandomizedIteration 0
+ * @run main/othervm RandomizedIteration 1
+ * @run main/othervm RandomizedIteration 2
+ * @run main/othervm RandomizedIteration 3
+ * @run main/othervm RandomizedIteration 4
+ * @run main/othervm RandomizedIteration verify 5
+ */
+
+import java.io.IOException;
+import java.io.PrintStream;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Set;
+
+import static java.util.stream.Collectors.toUnmodifiableMap;
+
+/**
+ * Test of randomized iteration of unmodifiable sets and maps.
+ *
+ * Usage: RandomizedIteration n
+ *            - writes files suffixed with 'n' containing set elements and map keys
+ *              in iteration order
+ *        RandomizedIteration "verify" count
+ *            - reads files 0..count-1 and checks to ensure that their orders differ
+ *
+ * The idea is to generate several test files by invoking this test with an arg
+ * of 0 through count-1. Then invoke the test once more with two args, the first being
+ * the word "verify" and the second arg being the count. This will read all the generated
+ * files and perform verification.
+ *
+ * The test is considered to pass if any of the runs result in different iteration
+ * orders. The randomization is not actually very random, so over many runs there is
+ * the possibility of a couple of the test files having the same order. That's ok, as
+ * long as the iteration order is usually different. The test fails if *all* of the
+ * iteration orders are the same.
+ */
+public class RandomizedIteration {
+    /**
+     * Generates a set and a map from the word array, and then writes
+     * text files "set.#" and "map.#" containing the set elements and
+     * map keys in iteration order.
+     *
+     * @param suffix number used for the file suffix
+     */
+    static void writeFiles(int suffix) throws IOException {
+        try (PrintStream setOut = new PrintStream("set." + suffix)) {
+            Set.of(WORDS)
+               .forEach(setOut::println);
+        }
+
+        try (PrintStream mapOut = new PrintStream("map." + suffix)) {
+            var map = Map.ofEntries(Arrays.stream(WORDS)
+                                          .map(word -> Map.entry(word, ""))
+                                          .toArray(Map.Entry<?, ?>[]::new));
+            map.keySet()
+               .forEach(mapOut::println);
+        }
+    }
+
+    /**
+     * Reads lines from each file derived from the prefix and index from 0..count-1
+     * into a list, computes its hashcode, and returns a set of those hashcodes.
+     * The hashcode of the list is order sensitive, so the same lines in a different
+     * order should have different hashcodes.
+     *
+     * @param prefix the file prefix
+     * @param count the number of files to read
+     * @return a set of hashcodes of each file
+     */
+    static Set<Integer> readFiles(String prefix, int count) throws IOException {
+        Set<Integer> hashes = new HashSet<>();
+        for (int suffix = 0; suffix < count; suffix++) {
+            String name = prefix + suffix;
+            int hash = Files.readAllLines(Paths.get(name)).hashCode();
+            System.out.println(name + ": " + hash);
+            hashes.add(hash);
+        }
+        return hashes;
+    }
+
+    /**
+     * Test main routine.
+     *
+     * @param args n | "verify" count
+     * @throws IOException if an error occurred
+     */
+    public static void main(String[] args) throws IOException {
+        if ("verify".equals(args[0])) {
+            int count = Integer.parseInt(args[1]);
+            System.out.println("Verifying " + count + " files.");
+            Set<Integer> setHashes = readFiles("set.", count);
+            Set<Integer> mapHashes = readFiles("map.", count);
+            if (setHashes.size() > 1 && mapHashes.size() > 1) {
+                System.out.println("Passed: differing iteration orders were detected.");
+            } else {
+                throw new AssertionError("FAILED: iteration order not randomized!");
+            }
+        } else {
+            int suffix = Integer.parseInt(args[0]);
+            System.out.println("Generating files: " + suffix);
+            writeFiles(suffix);
+        }
+    }
+
+    /**
+     * List of 63 words of 22 or more letters from BSD /usr/share/dict/words.
+     */
+    static final String[] WORDS = {
+        "anatomicophysiological",
+        "anthropomorphologically",
+        "aquopentamminecobaltic",
+        "blepharoconjunctivitis",
+        "blepharosphincterectomy",
+        "cholecystenterorrhaphy",
+        "cholecystoduodenostomy",
+        "choledochoduodenostomy",
+        "counterexcommunication",
+        "dacryocystoblennorrhea",
+        "dacryocystosyringotomy",
+        "deanthropomorphization",
+        "duodenocholecystostomy",
+        "electroencephalography",
+        "electrotelethermometer",
+        "epididymodeferentectomy",
+        "formaldehydesulphoxylate",
+        "formaldehydesulphoxylic",
+        "gastroenteroanastomosis",
+        "hematospectrophotometer",
+        "hexamethylenetetramine",
+        "hexanitrodiphenylamine",
+        "historicocabbalistical",
+        "hydropneumopericardium",
+        "hyperconscientiousness",
+        "laparocolpohysterotomy",
+        "lymphangioendothelioma",
+        "macracanthrorhynchiasis",
+        "microcryptocrystalline",
+        "naphthylaminesulphonic",
+        "nonrepresentationalism",
+        "omnirepresentativeness",
+        "pancreaticoduodenostomy",
+        "pancreaticogastrostomy",
+        "pathologicohistological",
+        "pathologicopsychological",
+        "pericardiomediastinitis",
+        "phenolsulphonephthalein",
+        "philosophicohistorical",
+        "philosophicotheological",
+        "photochronographically",
+        "photospectroheliograph",
+        "pneumohydropericardium",
+        "pneumoventriculography",
+        "polioencephalomyelitis",
+        "Prorhipidoglossomorpha",
+        "Pseudolamellibranchiata",
+        "pseudolamellibranchiate",
+        "pseudomonocotyledonous",
+        "pyopneumocholecystitis",
+        "scientificogeographical",
+        "scientificophilosophical",
+        "scleroticochorioiditis",
+        "stereophotomicrography",
+        "tetraiodophenolphthalein",
+        "theologicoastronomical",
+        "theologicometaphysical",
+        "thymolsulphonephthalein",
+        "thyroparathyroidectomize",
+        "thyroparathyroidectomy",
+        "transubstantiationalist",
+        "ureterocystanastomosis",
+        "zoologicoarchaeologist"
+    };
+}