1 /*
   2  * Copyright (c) 2013, 2014, 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 SanityTest
  26  * @summary Sanity check of String.intern() & GC
  27  * @modules java.base/jdk.internal.misc
  28  * @library /test/lib
  29  * @build sun.hotspot.WhiteBox
  30  * @run main ClassFileInstaller sun.hotspot.WhiteBox
  31  *                              sun.hotspot.WhiteBox$WhiteBoxPermission
  32  * @run main/othervm -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI SanityTest
  33  */
  34 
  35 import java.util.*;
  36 import sun.hotspot.WhiteBox;
  37 
  38 
  39 public class SanityTest {
  40     public static Object tmp;
  41     public static void main(String... args) {
  42 
  43         WhiteBox wb = WhiteBox.getWhiteBox();
  44         StringBuilder sb = new StringBuilder();
  45         sb.append("1234x"); sb.append("x56789");
  46         String str = sb.toString();
  47 
  48         if (wb.isInStringTable(str)) {
  49             throw new RuntimeException("String " + str + " is already interned");
  50         }
  51         str.intern();
  52         if (!wb.isInStringTable(str)) {
  53             throw new RuntimeException("String " + str + " is not interned");
  54         }
  55         str = sb.toString();
  56         wb.fullGC();
  57         if (wb.isInStringTable(str)) {
  58             throw new RuntimeException("String " + str + " is in StringTable even after GC");
  59         }
  60     }
  61 }