jdk-24/test/jdk/java/lang/Long/ToString.java
shaojin.wensj 4b43c25fe3 8310929: Optimization for Integer.toString
Reviewed-by: redestad, rriggs
2023-09-08 02:13:52 +00:00

90 lines
2.7 KiB
Java

/*
* Copyright (c) 2015, 2023, 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 8136500 8310929
* @summary Test Long.toString method for both compact and non-compact strings
* @run junit/othervm -XX:+CompactStrings ToString
* @run junit/othervm -XX:-CompactStrings ToString
*/
import org.junit.jupiter.api.Test;
import static org.junit.jupiter.api.Assertions.assertEquals;
public class ToString {
@Test
public void testBase10() {
test("-9223372036854775808", Long.MIN_VALUE);
test("9223372036854775807", Long.MAX_VALUE);
test("0", 0);
// Wiggle around the exponentially increasing base.
final int LIMIT = (1 << 15);
long base = 10000;
while (base < Long.MAX_VALUE / 10) {
for (int d = -LIMIT; d < LIMIT; d++) {
long c = base + d;
if (c > 0) {
buildAndTest(c);
}
}
base *= 10;
}
for (int c = 1; c < LIMIT; c++) {
buildAndTest(Long.MAX_VALUE - LIMIT + c);
}
}
private static void buildAndTest(long c) {
if (c <= 0) {
throw new IllegalArgumentException("Test bug: can only handle positives, " + c);
}
StringBuilder sbN = new StringBuilder();
StringBuilder sbP = new StringBuilder();
long t = c;
while (t > 0) {
char digit = (char) ('0' + (t % 10));
sbN.append(digit);
sbP.append(digit);
t = t / 10;
}
sbN.append("-");
sbN.reverse();
sbP.reverse();
test(sbN.toString(), -c);
test(sbP.toString(), c);
}
private static void test(String expected, long value) {
assertEquals(expected, Long.toString(value));
}
}