* used; or if the class exposes a public parameter-less constructor then it will be "new"d and
 * returned.
 *
 * <p>All default instances returned by {@link #get} are generics-safe. Clients won't get type
 * errors for using {@code get(Comparator.class)} as a {@code Comparator<Foo>}, for example.

import java.util.regex.MatchResult;
import java.util.regex.Pattern;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;
import org.jspecify.annotations.Nullable;

/**
 * Unit test for {@link ArbitraryInstances}.
 *
 * @author Ben Yu
 */
@NullUnmarked
public class ArbitraryInstancesTest extends TestCase {

  public void testGet_primitives() {

import java.lang.reflect.TypeVariable;
import java.util.Collections;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;
import org.jspecify.annotations.Nullable;

/**
 * Unit tests for {@link Invokable}.
 *
 * @author Ben Yu
 */
@AndroidIncompatible // lots of failures, possibly some related to bad equals() implementations?
@NullUnmarked
public class InvokableTest extends TestCase {

import java.util.Comparator;
import java.util.List;
import java.util.Locale;
import junit.framework.TestCase;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Unit test for {@link Chars}.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
@NullMarked
public class CharsTest extends TestCase {
  private static final char[] EMPTY = {};
  private static final char[] ARRAY1 = {(char) 1};

        return toMap(userProperties);
    }

    protected abstract Options parseCliOptions(LocalContext context);

    /**
     * Important: This method must return list of {@link CoreExtensions} in precedence order.
     */
    protected List<CoreExtensions> readCoreExtensionsDescriptor(LocalContext context) {
        ArrayList<CoreExtensions> result = new ArrayList<>();
        Path file;

import com.google.common.testing.SerializableTester;
import java.util.ArrayList;
import java.util.List;
import java.util.NavigableMap;
import org.jspecify.annotations.NullUnmarked;

/**
 * Tests for {@link TreeRangeSet}.
 *
 * @author Louis Wasserman
 * @author Chris Povirk
 */
@GwtIncompatible // TreeRangeSet
@NullUnmarked
public class TreeRangeSetTest extends AbstractRangeSetTest {

        array[i++] = (Long) e;
      }
      return create(array);
    }

    /**
     * Creates a new collection containing the given elements; implement this method instead of
     * {@link #create(Object...)}.
     */
    protected abstract List<Long> create(Long[] elements);

    @Override
    public Long[] createArray(int length) {
      return new Long[length];
    }

import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Tests for {@link ImmutableMultiset}.
 *
 * @author Jared Levy
 */
@GwtCompatible
@NullMarked
public class ImmutableMultisetTest extends TestCase {

  @J2ktIncompatible

    // Ideally we would also test the bitSize() overflow of this BF, but it runs out of heap space
    // BloomFilter.create(Funnels.unencodedCharsFunnel(), 244412641, 1e-11);
  }

  /**
   * Asserts that {@link BloomFilter#approximateElementCount} is within 1 percent of the expected
   * value.
   */
  private static void assertApproximateElementCountGuess(BloomFilter<?> bf, int sizeGuess) {

* データ変換
* データの検証
* 自動文書化

## 特殊な型とバリデーション

`str`や`int`、`float`のような通常の単数型の他にも、`str`を継承したより複雑な単数型を使うこともできます。

すべてのオプションをみるには、<a href="https://docs.pydantic.dev/latest/concepts/types/" class="external-link" target="_blank">Pydanticのエキゾチック な型</a>のドキュメントを確認してください。次の章でいくつかの例をみることができます。

例えば、`Image`モデルのように`url`フィールドがある場合、`str`の代わりにPydanticの`HttpUrl`を指定することができます:

{* ../../docs_src/body_nested_models/tutorial005.py hl[4,10] *}