System.setProperty("java.version", "15.0.1");

        String[] args = new String[] { "8-:-Xms512m", // From Java 8 onwards
                "11-:-Xmx2g", // From Java 11 onwards
                "17-:-XX:+UseG1GC", // From Java 17 onwards
                "21-:-XX:+UseZGC" // From Java 21 onwards
        };

        String[] result = JvmUtil.filterJvmOptions(args);
        assertEquals(2, result.length);

   */
  private static final SuccessorsFunction<Character> TWO_CYCLES_GRAPH =
      createDirectedGraph("ab", "ac", "bc", "cd", "da");

  /**
   * A tree-shaped graph that looks as follows (all edges are directed facing downwards):
   *
   * {@snippet :
   *        h
   *       /|\
   *      / | \
   *     /  |  \
   *    d   e   g
   *   /|\      |
   *  / | \     |
   * a  b  c    f
   * }
   */

   */
  private static final SuccessorsFunction<Character> TWO_CYCLES_GRAPH =
      createDirectedGraph("ab", "ac", "bc", "cd", "da");

  /**
   * A tree-shaped graph that looks as follows (all edges are directed facing downwards):
   *
   * {@snippet :
   *        h
   *       /|\
   *      / | \
   *     /  |  \
   *    d   e   g
   *   /|\      |
   *  / | \     |
   * a  b  c    f
   * }
   */

import java.util.Collection;
import java.util.Iterator;
import java.util.Objects;
import java.util.Set;
import org.jspecify.annotations.Nullable;

/**
 * A multiset which forwards all its method calls to another multiset. Subclasses should override
 * one or more methods to modify the behavior of the backing multiset as desired per the <a

      Header("if-none-match", ""),
      Header("if-range", ""),
      Header("if-unmodified-since", ""),
      Header("last-modified", ""),
      Header("link", ""),
      Header("location", ""),
      Header("max-forwards", ""),
      Header("proxy-authenticate", ""),
      Header("proxy-authorization", ""),
      Header("range", ""),
      Header("referer", ""),
      Header("refresh", ""),
      Header("retry-after", ""),

      return proxy;
    }
  }

  /**
   * Intercepts calls to a {@code Map} to check that {@code setUpRan} is true when they happen. Then
   * forwards the calls to the underlying {@code Map}.
   */
  private static class CheckSetUpInvocationHandler implements InvocationHandler, Serializable {
    private final Map<String, String> map;

import java.util.Collection;
import java.util.Iterator;
import java.util.Map;
import java.util.Objects;
import java.util.Set;
import org.jspecify.annotations.Nullable;

/**
 * A map which forwards all its method calls to another map. Subclasses should override one or more
 * methods to modify the behavior of the backing map as desired per the <a
 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.

import java.util.NavigableMap;
import java.util.NavigableSet;
import java.util.NoSuchElementException;
import java.util.SortedMap;
import org.jspecify.annotations.Nullable;

/**
 * A navigable map which forwards all its method calls to another navigable map. Subclasses should
 * override one or more methods to modify the behavior of the backing map as desired per the <a

import java.util.NavigableSet;
import java.util.NoSuchElementException;
import java.util.SortedMap;
import java.util.function.BiFunction;
import org.jspecify.annotations.Nullable;

/**
 * A navigable map which forwards all its method calls to another navigable map. Subclasses should
 * override one or more methods to modify the behavior of the backing map as desired per the <a

  /** The HTTP {@code Last-Event-ID} header field name. */
  public static final String LAST_EVENT_ID = "Last-Event-ID";

  /** The HTTP {@code Max-Forwards} header field name. */
  public static final String MAX_FORWARDS = "Max-Forwards";

  /** The HTTP {@code Origin} header field name. */
  public static final String ORIGIN = "Origin";

  /**