TestSuite suite = new TestSuite("java.util Sets");
    suite.addTest(testsForCheckedNavigableSet());
    suite.addTest(testsForEmptySet());
    suite.addTest(testsForEmptyNavigableSet());
    suite.addTest(testsForEmptySortedSet());
    suite.addTest(testsForSingletonSet());
    suite.addTest(testsForHashSet());
    suite.addTest(testsForLinkedHashSet());
    suite.addTest(testsForEnumSet());
    suite.addTest(testsForSynchronizedNavigableSet());

import jakarta.annotation.PreDestroy;

/**
 * Helper class for system-level operations and utilities.
 * This class provides methods for managing system properties, handling JSP files,
 * normalizing configurations, and other system-related tasks.
 */
public class SystemHelper {

    /**
     * Constructs a new system helper.
     */
    public SystemHelper() {
        // do nothing
    }

    #       e.g. foo or df:dfprop/system-password.txt|foo
    #       (NotRequired - Default '')
    #   o isSkipIfNotFoundPasswordFileAndDefault: Does it skip the user SQL statement
    #       when using password file but not found it and also default password?
    #       (NotRequired - Default false)
    #
    #; additionalUserMap = map:{
    #    ; system = map:{
    #        #; url = ...

        }
    }

    /**
     * Checks if the given URL represents a file system path.
     * Determines if the URL uses file system protocols that may require
     * special handling for content serving.
     *
     * @param url the URL to check
     * @return true if the URL is a file system path, false otherwise
     */
    protected boolean isFileSystemPath(final String url) {

  };

  @J2ktIncompatible
  @GwtIncompatible // suite
  @AndroidIncompatible // test-suite builders
  public static Test suite() {
    TestSuite suite = new TestSuite();

    // Not testing rowKeySet() or columnKeySet() of Table.transformValues()
    // since the transformation doesn't affect the row and column key sets.

    suite.addTest(
        SetTestSuiteBuilder.using(

```JSON
{
  "detail": "Inactive user"
}
```

## Recap { #recap }

You now have the tools to implement a complete security system based on `username` and `password` for your API.

Using these tools, you can make the security system compatible with any database and with any user or data model.

The only detail missing is that it is not actually "secure" yet.

      long remainingNanos = unit.toNanos(timeout);
      long end = System.nanoTime() + remainingNanos;

      while (true) {
        try {
          // CountDownLatch treats negative timeouts just like zero.
          return latch.await(remainingNanos, NANOSECONDS);
        } catch (InterruptedException e) {
          interrupted = true;
          remainingNanos = end - System.nanoTime();
        }
      }
    } finally {

        System.setProperty("test_var", "underscore");
        value = "${test_var}";
        assertEquals("underscore", ResourceUtil.resolve(value));

        // Clean up test properties
        System.clearProperty("var1");
        System.clearProperty("var2");
        System.clearProperty("special");
        System.clearProperty("123");
        System.clearProperty("test_var");
    }

 *     System.out.println(indexed.getIndex());
 *     System.out.println(indexed.getElement());
 * }
 * </pre>
 *
 * <pre>
 * import static org.codelibs.core.collection.IndexedIterator.*;
 * import static org.codelibs.core.io.LineIterator.*;
 *
 * BufferedReader reader = ...;
 * for (Indexed&lt;String&gt; indexed : indexed(iterable(reader))) {
 *     System.out.println(indexed.getIndex());

    System.out.printf("%.2f Executing call.%n", (System.nanoTime() - startNanos) / 1e9f);
    try (Response response = call.execute()) {
      System.out.printf("%.2f Call was expected to fail, but completed: %s%n",
          (System.nanoTime() - startNanos) / 1e9f, response);
    } catch (IOException e) {
      System.out.printf("%.2f Call failed as expected: %s%n",
          (System.nanoTime() - startNanos) / 1e9f, e);
    }
  }