Why is this an issue?

The Files.exists method has noticeably poor performance in JDK 8, and can slow an application significantly when used to check files that don’t actually exist.

The same goes for Files.notExists, Files.isDirectory and Files.isRegularFile from java.nio.file package.

Note that this rule is automatically disabled when the project’s sonar.java.source is not 8.

Noncompliant code example

Path myPath;
if(java.nio.file.Files.exists(myPath)) {  // Noncompliant
 // do something
}

Compliant solution

Path myPath;
if(myPath.toFile().exists())) {
 // do something
}

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