RFR: 8336240: Test com/sun/crypto/provider/Cipher/DES/PerformanceTest.java fails with java.lang.ArithmeticException

[Fernando Guallini]

The manual test Cipher/DES/PerformanceTest.java fails with ArithmeticException due to potential division by zero. The issue arises when calculating the elapsed time using end - start, which could result in zero milliseconds if start and end are identical due to the high speed of execution. This leads to a division error in the following code snippet:


start = System.currentTimeMillis();
end = System.currentTimeMillis();
int speed = (int)((data.length * count)/(end - start));

The fix is to provide a default value in case _end_ is not higher than _start_.

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Commit messages:
 - remove unused imports
 - tiny refactor
 - avoid dividing by zero

Changes: https://git.openjdk.org/jdk/pull/20135/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=20135&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8336240
  Stats: 7 lines in 2 files changed: 2 ins; 3 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/20135.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/20135/head:pull/20135

PR: https://git.openjdk.org/jdk/pull/20135