### Question:
CSSParseHelper { @Nonnull public static String unescapeURL (@Nonnull final String sEscapedURL) { int nIndex = sEscapedURL.indexOf (URL_ESCAPE_CHAR); if (nIndex < 0) { return sEscapedURL; } final StringBuilder aSB = new StringBuilder (sEscapedURL.length ()); int nPrevIndex = 0; do { aSB.append (sEscapedURL, nPrevIndex, nIndex); aSB.append (sEscapedURL, nIndex + 1, nIndex + 2); nPrevIndex = nIndex + 2; nIndex = sEscapedURL.indexOf (URL_ESCAPE_CHAR, nPrevIndex); } while (nIndex >= 0); aSB.append (sEscapedURL.substring (nPrevIndex)); return aSB.toString (); } private  CSSParseHelper(); @Nullable static String extractStringValue(@Nullable final String sStr); @Nonnull static String unescapeURL(@Nonnull final String sEscapedURL); @Nonnull static String trimUrl(@Nonnull final CharSequence s); @Nonnull static String splitNumber(@Nonnull final StringBuilder aPattern); @Nonnull static String validateIdentifier(@Nonnull final StringBuilder aPattern); @Nonnull static String unescapeUnicode(final StringBuilder aImage); @Nonnull static String unescapeOther(final StringBuilder aImage); static final char URL_ESCAPE_CHAR; }### Answer:
@Test public void testUnescapeCSSURL () { assertEquals ("bla.gif", CSSParseHelper.unescapeURL ("bla.gif")); assertEquals ("/foo/bla.gif", CSSParseHelper.unescapeURL ("/foo/bla.gif")); assertEquals ("/foo/bla().gif", CSSParseHelper.unescapeURL ("/foo/bla\\(\\).gif")); assertEquals ("\\\\server\\foo\\bla.gif", CSSParseHelper.unescapeURL ("\\\\\\\\server\\\\foo\\\\bla.gif")); }