CrawlerSystemException exception = new CrawlerSystemException("Print stack trace test");

        StringWriter stringWriter = new StringWriter();
        PrintWriter printWriter = new PrintWriter(stringWriter);
        exception.printStackTrace(printWriter);

        String stackTraceOutput = stringWriter.toString();
        assertNotNull(stackTraceOutput);
        assertTrue(stackTraceOutput.contains("CrawlerSystemException"));

    private StringWriter stringWriter;
    private PrintWriter printWriter;
    private ByteArrayOutputStream outputStream;
    private ServletOutputStream servletOutputStream;

    @BeforeEach
    void setUp() throws Exception {
        // Setup response writers
        stringWriter = new StringWriter();
        printWriter = new PrintWriter(stringWriter);
        outputStream = new ByteArrayOutputStream();

        private int status = 200;
        private final Map<String, String> headers = new HashMap<>();
        private final StringWriter stringWriter = new StringWriter();
        private final PrintWriter writer = new PrintWriter(stringWriter);

        @Override
        public void setStatus(int sc) {
            this.status = sc;
        }

        @Override
        public int getStatus() {

  public void testLineReading() throws IOException {
    File temp = createTempFile();
    assertNull(Files.readFirstLine(temp, UTF_8));
    assertTrue(Files.readLines(temp, UTF_8).isEmpty());

    PrintWriter w = new PrintWriter(Files.newWriter(temp, UTF_8));
    w.println("hello");
    w.println("");
    w.println(" world  ");
    w.println("");
    w.close();

    assertEquals("hello", Files.readFirstLine(temp, UTF_8));

  public void testLineReading() throws IOException {
    File temp = createTempFile();
    assertNull(Files.readFirstLine(temp, UTF_8));
    assertTrue(Files.readLines(temp, UTF_8).isEmpty());

    PrintWriter w = new PrintWriter(Files.newWriter(temp, UTF_8));
    w.println("hello");
    w.println("");
    w.println(" world  ");
    w.println("");
    w.close();

    assertEquals("hello", Files.readFirstLine(temp, UTF_8));

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintStream;
import java.io.PrintWriter;
import java.io.Reader;
import java.io.Serializable;
import java.io.StringReader;
import java.io.StringWriter;
import java.io.Writer;
import java.lang.reflect.AnnotatedElement;
import java.lang.reflect.Array;

    ArbitraryInstances.get(PrintStream.class).println("test");
    ArbitraryInstances.get(PrintWriter.class).println("test");
    assertNotNull(ArbitraryInstances.get(File.class));
    assertFreshInstanceReturned(
        ByteArrayOutputStream.class, OutputStream.class,
        Writer.class, StringWriter.class,
        PrintStream.class, PrintWriter.class);
    assertEquals(ByteSource.empty(), ArbitraryInstances.get(ByteSource.class));

    ArbitraryInstances.get(PrintStream.class).println("test");
    ArbitraryInstances.get(PrintWriter.class).println("test");
    assertNotNull(ArbitraryInstances.get(File.class));
    assertFreshInstanceReturned(
        ByteArrayOutputStream.class, OutputStream.class,
        Writer.class, StringWriter.class,
        PrintStream.class, PrintWriter.class);
    assertEquals(ByteSource.empty(), ArbitraryInstances.get(ByteSource.class));

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintStream;
import java.io.PrintWriter;
import java.io.Reader;
import java.io.Serializable;
import java.io.StringReader;
import java.io.StringWriter;
import java.io.Writer;
import java.lang.reflect.AnnotatedElement;
import java.lang.reflect.Array;

   * {@link Throwable#getStackTrace()}.
   */
  @GwtIncompatible // java.io.PrintWriter, java.io.StringWriter
  public static String getStackTraceAsString(Throwable throwable) {
    StringWriter stringWriter = new StringWriter();
    throwable.printStackTrace(new PrintWriter(stringWriter));
    return stringWriter.toString();
  }

  /**