1 /*

     2  * Copyright 2010 Google Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

    20  * CA 95054 USA or visit www.sun.com if you need additional information or

    21  * have any questions.

    22  */

    23 

    24 /*

    25  * @test

    26  * @bug 6952330

    27  * @summary Test StringBuffer/StringBuilder capacity handling.

    28  */

    29 

    30 import java.util.Random;

    31 

    32 public class Capacity {

    33     void test(String[] args) throws Throwable {

    34         Random rnd = new Random();

    35         int[] sizes = { 0, 1, rnd.nextInt(10), rnd.nextInt(1000) };

    36         for (int size : sizes) {

    37             equal(16, new StringBuffer().capacity());

    38             equal(16, new StringBuilder().capacity());

    39             StringBuffer buff = new StringBuffer(size);

    40             StringBuilder bild = new StringBuilder(size);

    41             equal(size, buff.capacity());

    42             equal(size, bild.capacity());

    43             buff.ensureCapacity(size);

    44             bild.ensureCapacity(size);

    45             equal(size, buff.capacity());

    46             equal(size, bild.capacity());

    47             buff.ensureCapacity(size+1);

    48             bild.ensureCapacity(size+1);

    49             equal(size*2+2, buff.capacity());

    50             equal(size*2+2, bild.capacity());

    51             size = buff.capacity();

    52             buff.ensureCapacity(size*2+1);

    53             bild.ensureCapacity(size*2+1);

    54             equal(size*2+2, buff.capacity());

    55             equal(size*2+2, bild.capacity());

    56             size = buff.capacity();

    57             int newSize = size * 2 + 3;

    58             buff.ensureCapacity(newSize);

    59             bild.ensureCapacity(newSize);

    60             equal(newSize, buff.capacity());

    61             equal(newSize, bild.capacity());

    62             buff.ensureCapacity(0);

    63             bild.ensureCapacity(0);

    64             equal(newSize, buff.capacity());

    65             equal(newSize, bild.capacity());

    66         }

    67     }

    68 

    69     //--------------------- Infrastructure ---------------------------

    70     volatile int passed = 0, failed = 0;

    71     void pass() {passed++;}

    72     void fail() {failed++; Thread.dumpStack();}

    73     void fail(String msg) {System.err.println(msg); fail();}

    74     void unexpected(Throwable t) {failed++; t.printStackTrace();}

    75     void check(boolean cond) {if (cond) pass(); else fail();}

    76     void equal(Object x, Object y) {

    77         if (x == null ? y == null : x.equals(y)) pass();

    78         else fail(x + " not equal to " + y);}

    79     public static void main(String[] args) throws Throwable {

    80         new Capacity().instanceMain(args);}

    81     public void instanceMain(String[] args) throws Throwable {

    82         try {test(args);} catch (Throwable t) {unexpected(t);}

    83         System.out.printf("%nPassed = %d, failed = %d%n%n", passed, failed);

    84         if (failed > 0) throw new AssertionError("Some tests failed");}

    85 }