How to use

setTabulationWidth

method

in

org.apache.sis.io.LineAppender

/**
 * Sets the tab width.
 *
 * @param  tabWidth The tab width. Must be greater than 0.
 * @throws IllegalArgumentException if {@code tabWidth} is not greater than 0.
 */
public void setTabWidth(final int tabWidth) throws IllegalArgumentException {
  synchronized (lock) {
    formatter.setTabulationWidth(tabWidth);
  }
}

/**
 * Returns the exception trace as a string. This method get the stack trace using the
 * {@link Throwable#printStackTrace(PrintWriter)} method, then replaces the tabulation
 * characters by 4 white spaces.
 *
 * @param exception The exception to format.
 * @return A string representation of the given exception.
 */
public static String formatStackTrace(final Throwable exception) {
  final StringWriter writer = new StringWriter();
  exception.printStackTrace(new PrintWriter(writer));
  final StringBuilder buffer = new StringBuilder();
  final LineAppender formatter = new LineAppender(buffer);
  formatter.setTabulationWidth(TAB_WIDTH);
  try {
    formatter.append(writer.toString());
  } catch (IOException e) {
    throw new AssertionError(e);
  }
  return buffer.toString();
}

buffer  = str.getBuffer().append(header);
printer = new PrintWriter(IO.asWriter(writer));
writer.setTabulationWidth(4);

buffer  = str.getBuffer().append(header);
printer = new PrintWriter(IO.asWriter(writer));
writer.setTabulationWidth(4);

  /**
   * Tests a call to {@link LineAppender#flush()} interleaved between two lines,
   * where the second line begin with a tabulation.
   *
   * @throws IOException should never happen, since we are writing in a {@link StringBuilder}.
   *
   * @see <a href="https://issues.apache.org/jira/browse/SIS-140">SIS-140</a>
   */
  @Test
  public void testInterleavedFlush() throws IOException {
    final LineAppender f = (LineAppender) appender;
    f.setTabulationWidth(4);
    f.append("S1");
    f.flush();
    f.append("\tS2");
    assertOutputEquals(f.isTabulationExpanded() ? "S1  S2" : "S1\tS2");
  }
}