| /* |
| * Copyright (c) 2016, 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 8149330 |
| * @summary Basic set of tests of capacity management |
| * @run testng Capacity |
| */ |
| |
| import java.lang.reflect.Field; |
| import java.util.AbstractList; |
| import java.util.ArrayList; |
| import java.util.Collections; |
| import java.util.List; |
| import java.util.SplittableRandom; |
| |
| import org.testng.annotations.Test; |
| import org.testng.annotations.DataProvider; |
| import static org.testng.Assert.*; |
| |
| public class Capacity { |
| static final int DEFAULT_CAPACITY = 16; |
| |
| private static int newCapacity(int oldCapacity, |
| int desiredCapacity) |
| { |
| return Math.max(oldCapacity * 2 + 2, desiredCapacity); |
| } |
| |
| private static int nextNewCapacity(int oldCapacity) { |
| return newCapacity(oldCapacity, oldCapacity + 1); |
| } |
| |
| @Test(dataProvider = "singleChar") |
| public void defaultCapacity(Character ch) { |
| StringBuilder sb = new StringBuilder(); |
| assertEquals(sb.capacity(), DEFAULT_CAPACITY); |
| for (int i = 0; i < DEFAULT_CAPACITY; i++) { |
| sb.append(ch); |
| assertEquals(sb.capacity(), DEFAULT_CAPACITY); |
| } |
| sb.append(ch); |
| assertEquals(sb.capacity(), nextNewCapacity(DEFAULT_CAPACITY)); |
| } |
| |
| @Test(dataProvider = "charCapacity") |
| public void explicitCapacity(Character ch, int initCapacity) { |
| StringBuilder sb = new StringBuilder(initCapacity); |
| assertEquals(sb.capacity(), initCapacity); |
| for (int i = 0; i < initCapacity; i++) { |
| sb.append(ch); |
| assertEquals(sb.capacity(), initCapacity); |
| } |
| sb.append(ch); |
| assertEquals(sb.capacity(), nextNewCapacity(initCapacity)); |
| } |
| |
| @Test(dataProvider = "singleChar") |
| public void sbFromString(Character ch) { |
| String s = "string " + ch; |
| int expectedCapacity = s.length() + DEFAULT_CAPACITY; |
| StringBuilder sb = new StringBuilder(s); |
| assertEquals(sb.capacity(), expectedCapacity); |
| for (int i = 0; i < DEFAULT_CAPACITY; i++) { |
| sb.append(ch); |
| assertEquals(sb.capacity(), expectedCapacity); |
| } |
| sb.append(ch); |
| assertEquals(sb.capacity(), nextNewCapacity(expectedCapacity)); |
| } |
| |
| @Test(dataProvider = "singleChar") |
| public void sbFromCharSeq(Character ch) { |
| CharSequence cs = new MyCharSeq("char seq " + ch); |
| int expectedCapacity = cs.length() + DEFAULT_CAPACITY; |
| StringBuilder sb = new StringBuilder(cs); |
| assertEquals(sb.capacity(), expectedCapacity); |
| for (int i = 0; i < DEFAULT_CAPACITY; i++) { |
| sb.append(ch); |
| assertEquals(sb.capacity(), expectedCapacity); |
| } |
| sb.append(ch); |
| assertEquals(sb.capacity(), nextNewCapacity(expectedCapacity)); |
| } |
| |
| @Test(dataProvider = "charCapacity") |
| public void ensureCapacity(Character ch, int cap) { |
| StringBuilder sb = new StringBuilder(0); |
| assertEquals(sb.capacity(), 0); |
| sb.ensureCapacity(cap); // only has effect if cap > 0 |
| int newCap = (cap == 0) ? 0 : newCapacity(0, cap); |
| assertEquals(sb.capacity(), newCap); |
| sb.ensureCapacity(newCap + 1); |
| assertEquals(sb.capacity(), nextNewCapacity(newCap)); |
| sb.append(ch); |
| assertEquals(sb.capacity(), nextNewCapacity(newCap)); |
| } |
| |
| @Test(dataProvider = "negativeCapacity", |
| expectedExceptions = NegativeArraySizeException.class) |
| public void negativeInitialCapacity(int negCap) { |
| StringBuilder sb = new StringBuilder(negCap); |
| } |
| |
| @Test(dataProvider = "negativeCapacity") |
| public void ensureNegativeCapacity(int negCap) { |
| StringBuilder sb = new StringBuilder(); |
| sb.ensureCapacity(negCap); |
| assertEquals(sb.capacity(), DEFAULT_CAPACITY); |
| } |
| |
| @Test(dataProvider = "charCapacity") |
| public void trimToSize(Character ch, int cap) { |
| StringBuilder sb = new StringBuilder(cap); |
| int halfOfCap = cap / 2; |
| for (int i = 0; i < halfOfCap; i++) { |
| sb.append(ch); |
| } |
| sb.trimToSize(); |
| // according to the spec, capacity doesn't have to |
| // become exactly the size |
| assertTrue(sb.capacity() >= halfOfCap); |
| } |
| |
| @DataProvider |
| public Object[][] singleChar() { |
| return new Object[][] { {'J'}, {'\u042b'} }; |
| } |
| |
| @DataProvider |
| public Object[][] charCapacity() { |
| return new Object[][] { |
| {'J', 0}, |
| {'J', 1}, |
| {'J', 15}, |
| {'J', DEFAULT_CAPACITY}, |
| {'J', 1024}, |
| {'\u042b', 0}, |
| {'\u042b', 1}, |
| {'\u042b', 15}, |
| {'\u042b', DEFAULT_CAPACITY}, |
| {'\u042b', 1024}, |
| }; |
| } |
| |
| @DataProvider |
| public Object[][] negativeCapacity() { |
| return new Object[][] { {-1}, {Integer.MIN_VALUE} }; |
| } |
| |
| private static class MyCharSeq implements CharSequence { |
| private CharSequence s; |
| public MyCharSeq(CharSequence s) { this.s = s; } |
| public char charAt(int i) { return s.charAt(i); } |
| public int length() { return s.length(); } |
| public CharSequence subSequence(int st, int e) { |
| return s.subSequence(st, e); |
| } |
| public String toString() { return s.toString(); } |
| } |
| } |