/*
* Copyright ( c ) 2016 , 2020 , 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 8218227
* @ summary Capacity should not get close to Integer . MAX_VALUE unless
* necessary
* @ requires ( sun . arch . data . model = = " 64 " & os . maxMemory > = 8 G )
* @ run main / othervm - Xms6G - Xmx6G - XX : + CompactStrings HugeCapacity true
* @ run main / othervm - Xms6G - Xmx6G - XX : - CompactStrings HugeCapacity false
*/
public class HugeCapacity {
private static int failures = 0 ;
public static void main(String[] args) {
if (args.length == 0 ) {
throw new IllegalArgumentException("Need the argument" );
}
boolean isCompact = Boolean .parseBoolean(args[0 ]);
testLatin1(isCompact);
testUtf16();
testHugeInitialString();
testHugeInitialCharSequence();
if (failures > 0 ) {
throw new RuntimeException(failures + " tests failed" );
}
}
private static void testLatin1(boolean isCompact) {
try {
int divisor = isCompact ? 2 : 4 ;
StringBuilder sb = new StringBuilder();
sb.ensureCapacity(Integer.MAX_VALUE / divisor);
sb.ensureCapacity(Integer.MAX_VALUE / divisor + 1 );
} catch (OutOfMemoryError oom) {
oom.printStackTrace();
failures++;
}
}
private static void testUtf16() {
try {
StringBuilder sb = new StringBuilder();
sb.append('\u042b' );
sb.ensureCapacity(Integer.MAX_VALUE / 4 );
sb.ensureCapacity(Integer.MAX_VALUE / 4 + 1 );
} catch (OutOfMemoryError oom) {
oom.printStackTrace();
failures++;
}
}
private static void testHugeInitialString() {
try {
String str = "Z" .repeat(Integer.MAX_VALUE - 8 );
StringBuilder sb = new StringBuilder(str);
} catch (OutOfMemoryError ignore) {
} catch (Throwable unexpected) {
unexpected.printStackTrace();
failures++;
}
}
private static void testHugeInitialCharSequence() {
try {
CharSequence seq = new MyHugeCharSeq();
StringBuilder sb = new StringBuilder(seq);
} catch (OutOfMemoryError ignore) {
} catch (Throwable unexpected) {
unexpected.printStackTrace();
failures++;
}
}
private static class MyHugeCharSeq implements CharSequence {
public char charAt(int i) {
throw new UnsupportedOperationException();
}
public int length() { return Integer.MAX_VALUE; }
public CharSequence subSequence(int st, int e) {
throw new UnsupportedOperationException();
}
public String toString() { return "" ; }
}
}
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