1 /* 2 * Copyright (c) 2015, 2018 Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 24 /** 25 * @test 26 * @bug 8080535 8191410 8215194 27 * @summary Expected size of Character.UnicodeBlock.map is not optimal 28 * @library /test/lib 29 * @modules java.base/java.lang:open 30 * java.base/java.util:open 31 * @build jdk.test.lib.util.OptimalCapacity 32 * @run main OptimalMapSize 33 */ 34 35 import java.lang.reflect.Field; 36 import jdk.test.lib.util.OptimalCapacity; 37 38 // What will be the number of the Unicode blocks in the future. 39 // 40 // According to http://www.unicode.org/versions/Unicode7.0.0/ , 41 // in Unicode 7 there will be added 32 new blocks (96 with aliases). 42 // According to http://www.unicode.org/versions/beta-8.0.0.html , 43 // in Unicode 8 there will be added 10 more blocks (30 with aliases). 44 // 45 // After implementing support of Unicode 9 and 10 in Java, there will 46 // be 638 entries in Character.UnicodeBlock.map. 47 // 48 // As of Unicode 11, 667 entries are expected. 49 // 50 // Initialization of the map and this test will have to be adjusted 51 // accordingly then. 52 // 53 // Note that HashMap's implementation aligns the initial capacity to 54 // a power of two size, so it will end up 1024 (and thus succeed) in 55 // cases, such as 638 and 667. 56 57 public class OptimalMapSize { 58 public static void main(String[] args) throws Throwable { 59 // The initial size of Character.UnicodeBlock.map. 60 // See src/java.base/share/classes/java/lang/Character.java 61 Field f = Character.UnicodeBlock.class.getDeclaredField("MAP_CAPACITY"); 62 f.setAccessible(true); 63 int initialCapacity = f.getInt(null); 64 assert initialCapacity == (int)(667 / 0.75f + 1.0f); 65 66 OptimalCapacity.ofHashMap(Character.UnicodeBlock.class, 67 "map", initialCapacity); 68 } 69 }