// access some of the elements
      Random random = new Random();
      List<ReferenceEntry<Object, Object>> reads = new ArrayList<>();
      Iterator<ReferenceEntry<Object, Object>> i = readOrder.iterator();
      while (i.hasNext()) {
        ReferenceEntry<Object, Object> entry = i.next();
        if (random.nextBoolean()) {
          map.get(entry.getKey(), loader);
          reads.add(entry);

    byte[] expectedBytes = new byte[size];
    byte[] bytes = newPreFilledByteArray(1024);

    // Setup
    File file = createTempFile();
    Files.write(bytes, file);

    Random random = new Random();
    random.nextBytes(expectedBytes);

    // Test
    MappedByteBuffer map = Files.map(file, MapMode.READ_WRITE);
    map.put(expectedBytes);

    // Verify

    Comparator<byte[]> comparator1 = UnsignedBytes.lexicographicalComparator();
    Comparator<byte[]> comparator2 = UnsignedBytes.lexicographicalComparatorJavaImpl();
    Random rnd = new Random(714958103);
    for (int trial = 0; trial < 100; trial++) {
      byte[] left = new byte[1 + rnd.nextInt(32)];
      rnd.nextBytes(left);
      byte[] right = left.clone();

The `EventListener.Factory` also makes it possible to limit metrics to a subset of calls. This one captures metrics on a random 10%:

```java
class MetricsEventListener extends EventListener {
  private static final Factory FACTORY = new Factory() {
    @Override public EventListener create(Call call) {
      if (Math.random() < 0.10) {
        return new MetricsEventListener(call);
      } else {
        return EventListener.NONE;

#!/bin/bash
#

set -e
set -E
set -o pipefail

if [ ! -x "$PWD/minio" ]; then
	echo "minio executable binary not found in current directory"
	exit 1
fi

WORK_DIR="$PWD/.verify-$RANDOM"

export MINT_MODE=core
export MINT_DATA_DIR="$WORK_DIR/data"
export SERVER_ENDPOINT="127.0.0.1:9000"
export MC_HOST_verify="http://minio:minio123@${SERVER_ENDPOINT}/"
export MC_HOST_verify_ipv6="http://minio:minio123@[::1]:9000/"

func (m *Man) BeforeUpdate(tx *gorm.DB) (err error) {
	if !tx.Statement.Changed("age") {
		return nil
	}
	return nil
}

func TestSubModel(t *testing.T) {
	man := Man{Age: 18, Name: "random-name"}
	if err := DB.Create(&man).Error; err != nil {
		t.Fatalf("unexpected error: %v", err)
	}

	if err := DB.Model(&man).Where("id = ?", man.ID).Updates(struct {
		Age int
	}{Age: 20}).Error; err != nil {

// Trivial collisions are avoided, but this is by no means a strong hash.
func hashDeterministicString(m map[string]string) uint64 {
	// Seed (random)
	crc := uint64(0xc2b40bbac11a7295)
	// Xor each value to make order independent
	for k, v := range m {
		// Separate key and value with an individual xor with a random number.
		// Add values of each, so they cannot be trivially collided.

	}{
		{"shastring", "", "shastring"},
		{emptySHA256, "", emptySHA256},
		{"", "", emptySHA256},
		{"", "X-Amz-Credential=random", unsignedPayload},
		{"", "X-Amz-Credential=random&X-Amz-Content-Sha256=" + unsignedPayload, unsignedPayload},
		{"", "X-Amz-Credential=random&X-Amz-Content-Sha256=shastring", "shastring"},
	}

	for i, testCase := range testCases {

    utf8Lengths.put(MIN_SUPPLEMENTARY_CODE_POINT, 4);
    utf8Lengths.put(MAX_CODE_POINT, 4);

    Integer[] codePoints = utf8Lengths.keySet().toArray(new Integer[] {});
    StringBuilder sb = new StringBuilder();
    Random rnd = new Random();
    for (int trial = 0; trial < 100; trial++) {
      sb.setLength(0);
      int utf8Length = 0;
      for (int i = 0; i < 6; i++) {
        Integer randomCodePoint = codePoints[rnd.nextInt(codePoints.length)];

    ArbitraryInstances.get(Stopwatch.class).start();
    assertThat(ArbitraryInstances.get(Ticker.class)).isNotNull();
    assertFreshInstanceReturned(Random.class);
    assertEquals(
        ArbitraryInstances.get(Random.class).nextInt(),
        ArbitraryInstances.get(Random.class).nextInt());
  }

  public void testGet_concurrent() {
    assertTrue(ArbitraryInstances.get(BlockingDeque.class).isEmpty());