void setValueReference(ValueReference<K, V> valueReference);

  /** Returns the next entry in the chain. */
  @CheckForNull
  ReferenceEntry<K, V> getNext();

  /** Returns the entry's hash. */
  int getHash();

  /** Returns the key for this entry. */
  @CheckForNull
  K getKey();

  /*
   * Used by entries that use access order. Access entries are maintained in a doubly-linked list.

        HashCode hash = resourceHasher.hash(zipEntryContext);
        if (hash != null) {
            fingerprints.add(new DefaultFileSystemLocationFingerprint(zipEntryContext.getFullName(), FileType.RegularFile, hash));
        }
    }

    private DefaultFileSystemLocationFingerprint newZipMarker(String relativePath) {

                SourceFileState state = incrementalCompilation.getFinalState().getState(sourceFile);
                final HashCode hash = state.getHash();
                List<String> headers = new ArrayList<>();
                for (IncludeFileEdge edge : state.getEdges()) {
                    if (hash.equals(edge.getIncludedBy())) {
                        headers.add(edge.getIncludePath());
                    }
                }

        when:
        def hash = resourceHasher.hash(zipEntryContext)

        then:
        1 * zipEntryContext.getEntry() >> zipEntry
        2 * zipEntry.getName() >> 'String.class'
        1 * zipEntry.getContent() >> classContent
        1 * apiClassExtractor.extractApiClassFrom(_) >> { args -> throw new Exception("Boom!") }

        and:
        hash == Hashing.hashBytes(classContent)

        and:

import org.gradle.internal.fingerprint.hashing.ResourceHasher;
import org.gradle.internal.fingerprint.hashing.ZipEntryContext;
import org.gradle.internal.hash.HashCode;
import org.gradle.internal.hash.Hasher;
import org.gradle.internal.hash.Hashing;
import org.gradle.internal.io.IoFunction;
import org.gradle.internal.normalization.java.ApiClassExtractor;
import org.gradle.internal.snapshot.RegularFileSnapshot;

    try {
      tester.addEquivalenceGroup(group1Item1, group1Item2).test();
    } catch (AssertionFailedError expected) {
      String expectedMessage =
          "the hash (1) of TestObject{group=1, item=1} [group 1, item 1] must be "
              + "equal to the hash (2) of TestObject{group=1, item=2} [group 1, item 2]";
      if (!expected.getMessage().contains(expectedMessage)) {

    try {
      tester.addEquivalenceGroup(group1Item1, group1Item2).test();
    } catch (AssertionFailedError expected) {
      String expectedMessage =
          "the hash (1) of TestObject{group=1, item=1} [group 1, item 1] must be "
              + "equal to the hash (2) of TestObject{group=1, item=2} [group 1, item 2]";
      if (!expected.getMessage().contains(expectedMessage)) {

        }
        return Optional.of(new DirectorySnapshot(targetPath, name, getAccessType(), contentHash, childMapFromSorted(relocatedChildren.build())));
    }

    @Override
    public HashCode getHash() {
        return contentHash;
    }

    @Override
    public FileType getType() {
        return FileType.Directory;
    }

    @Override

	{"runtime.memhash32", 1},
	{"runtime.memhash64", 1},
	{"runtime.memhash128", 1},
	{"runtime.f32hash", 1},
	{"runtime.f64hash", 1},
	{"runtime.c64hash", 1},
	{"runtime.c128hash", 1},
	{"runtime.strhash", 1},
	{"runtime.interhash", 1},
	{"runtime.nilinterhash", 1},
	{"runtime.int64div", 1},
	{"runtime.uint64div", 1},
	{"runtime.int64mod", 1},
	{"runtime.uint64mod", 1},
	{"runtime.float64toint64", 1},

        def snapshotContext = snapshotContext(file)
        def zipContext = zipContext(file)

        when:
        hasher.hash(snapshotContext)

        then:
        1 * delegate.hash(snapshotContext)

        when:
        hasher.hash(zipContext)

        then:
        1 * delegate.hash(zipContext)

        where:
        description               | contents
        "png content"             | content.PNG_CONTENT