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*
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* 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
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*
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* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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*/
/*
* @test
* @bug 4944561
* @summary Test hashCode() to have less than 10% of hash code conflicts.
* @modules jdk.localedata
*/
import java.util.*;
public class HashCodeTest {
public static void main(String[] args) {
Locale[] locales = Locale.getAvailableLocales();
int min = Integer.MAX_VALUE;
int max = Integer.MIN_VALUE;
Map map = new HashMap(locales.length);
int conflicts = 0;
for (int i = 0; i < locales.length; i++) {
Locale loc = locales[i];
int hc = loc.hashCode();
min = Math.min(hc, min);
max = Math.max(hc, max);
Integer key = new Integer(hc);
if (map.containsKey(key)) {
conflicts++;
System.out.println("conflict: " + (Locale) map.get(key) + ", " + loc);
} else {
map.put(key, loc);
}
}
System.out.println(locales.length+" locales: conflicts="+conflicts
+", min="+min+", max="+max +", diff="+(max-min));
if (conflicts >= (locales.length / 10)) {
throw new RuntimeException("too many conflicts: " + conflicts
+ " per " + locales.length + " locales");
}
}
}