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/*
* Copyright (c) 2015, 2017, 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.
*
*/
import sun.hotspot.WhiteBox;
public class InternStringTest {
public static String passed_output1 = "Found shared string.";
public static String passed_output2 = "Shared strings are equal.";
public static String passed_output3 = "Found shared string containing latin1 supplement chars.";
public static String passed_output4 = "Found shared string containing non-western chars.";
public static final String latin1Sup = "XXXX \u00a3 YYYY"; // \u00a3 = The pound sign
public static final String nonWestern = "XXXX \u5678 YYYY"; // \u5678 = Unicode Han Character 'ton (metric or English)'
public static void main(String[] args) throws Exception {
WhiteBox wb = WhiteBox.getWhiteBox();
// All string literals are shared.
String shared1 = "LiveOak";
String interned1 = shared1.intern();
if (wb.areSharedStringsIgnored() || wb.isShared(interned1)) {
System.out.println(passed_output1);
} else {
throw new RuntimeException("Failed: String is not shared.");
}
// Test 2: shared_string1.intern() == shared_string2.intern()
String shared2 = "LiveOak";
String interned2 = shared2.intern();
if (interned1 == interned2) {
System.out.println(passed_output2);
} else {
throw new RuntimeException("Not equal!");
}
// Test 3: interned strings with a char in latin1 supplement block [\u0080-\u00ff]
{
String a = "X" + latin1Sup.substring(1);
String b = a.intern();
if (wb.areSharedStringsIgnored() || wb.isShared(b)) {
System.out.println(passed_output3);
} else {
throw new RuntimeException("Failed: expected shared string with latin1-supplement chars.");
}
}
// Test 5: interned strings with non-western characters
{
String a = "X" + nonWestern.substring(1);
String b = a.intern();
if (wb.areSharedStringsIgnored() || wb.isShared(b)) {
System.out.println(passed_output4);
} else {
throw new RuntimeException("Failed: expected shared string with non-western chars.");
}
}
}
}
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