// io.CopyN done shortly afterwards to trigger any IO errors.
	var seekSkipped int64 // Number of bytes skipped via Seek
	if sr, ok := r.(io.Seeker); ok && n > 1 {
		// Not all io.Seeker can actually Seek. For example, os.Stdin implements
		// io.Seeker, but calling Seek always returns an error and performs
		// no action. Thus, we try an innocent seek to the current position
		// to see if Seek is really supported.

   * a modest limit on `byteCount`, such as 1 MiB.
   */
  @Throws(IOException::class)
  fun peekBody(byteCount: Long): ResponseBody {
    val peeked = body.source().peek()
    val buffer = Buffer()
    peeked.request(byteCount)
    buffer.write(peeked, minOf(byteCount, peeked.buffer.size))
    return buffer.asResponseBody(body.contentType(), buffer.size)
  }

  @JvmName("-deprecated_body")
  @Deprecated(

import java.io.IOException;
import java.util.List;
import junit.framework.TestCase;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Tests for {@link Closer}.
 *
 * @author Colin Decker
 */
public class CloserTest extends TestCase {

  private TestSuppressor suppressor;

  @Override
  protected void setUp() throws Exception {
    suppressor = new TestSuppressor();
  }

# Classes as Dependencies

Before diving deeper into the **Dependency Injection** system, let's upgrade the previous example.

## A `dict` from the previous example

In the previous example, we were returning a `dict` from our dependency ("dependable"):

//// tab | Python 3.10+

```Python hl_lines="9"
{!> ../../docs_src/dependencies/tutorial001_an_py310.py!}
```

////

//// tab | Python 3.9+

```Python hl_lines="11"

 * Closeable}. A {@link java.io.Reader} implements both of those interfaces. Similarly for {@code
 * Appendable & Closeable} and {@link java.io.Writer}.
 *
 * @author Chris Nokleberg
 * @author Bin Zhu
 * @author Colin Decker
 * @since 1.0
 */
@J2ktIncompatible
@GwtIncompatible
@ElementTypesAreNonnullByDefault
public final class CharStreams {

  // 2K chars (4K bytes)
  private static final int DEFAULT_BUF_SIZE = 0x800;

import java.nio.CharBuffer;
import java.util.Arrays;
import java.util.logging.Logger;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * {@link SourceSinkFactory} implementations.
 *
 * @author Colin Decker
 */
public class SourceSinkFactories {

  private SourceSinkFactories() {}

  public static CharSourceFactory stringCharSourceFactory() {
    return new StringSourceFactory();
  }

			entry:    "src/dir/",
			dir:      "src/",
			sep:      slashSeparator,
			want:     true,
		},
		{
			testName: "deeper-file",
			entry:    "src/dir/somewhere.ext",
			dir:      "src/",
			sep:      slashSeparator,
			want:     false,
		},
		{
			testName: "deeper-dir",
			entry:    "src/dir/somewhere/",
			dir:      "src/",
			sep:      slashSeparator,
			want:     false,
		},
		{

import java.util.EnumSet;
import junit.framework.TestSuite;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Tests for the default implementations of {@code ByteSource} methods.
 *
 * @author Colin Decker
 */
public class ByteSourceTest extends IoTestCase {

  @AndroidIncompatible // Android doesn't understand suites whose tests lack default constructors.
  public static TestSuite suite() {

import java.util.EnumSet;
import java.util.List;
import java.util.stream.Stream;
import junit.framework.TestSuite;

/**
 * Tests for the default implementations of {@code CharSource} methods.
 *
 * @author Colin Decker
 */
public class CharSourceTest extends IoTestCase {

  @AndroidIncompatible // Android doesn't understand suites whose tests lack default constructors.
  public static TestSuite suite() {

import java.io.IOException;
import java.util.List;
import junit.framework.TestCase;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Tests for {@link Closer}.
 *
 * @author Colin Decker
 */
public class CloserTest extends TestCase {

  private TestSuppressor suppressor;

  @Override
  protected void setUp() throws Exception {
    suppressor = new TestSuppressor();
  }