判斷是否為空格：
1. Character.isWhitespace(source.charAt(1));
java.lang.Character.isWhitespace(int codePoint) 確定指定字符（Unicode代碼點）是根據(jù)Java空白。一個字符是一個Java空白字符，當且僅當它滿足下列條件之一,返回true，否則返回false：

It is a Unicode space character (SPACE_SEPARATOR, LINE_SEPARATOR, or PARAGRAPH_SEPARATOR) but is not also a non-breaking space ('\u00A0', '\u2007', '\u202F').
It is '\t', U+0009 HORIZONTAL TABULATION.
It is '\n', U+000A LINE FEED.
It is '\u000B', U+000B VERTICAL TABULATION.
It is '\f', U+000C FORM FEED.
It is '\r', U+000D CARRIAGE RETURN.
It is '\u001C', U+001C FILE SEPARATOR.
It is '\u001D', U+001D GROUP SEPARATOR.
It is '\u001E', U+001E RECORD SEPARATOR.
It is '\u001F', U+001F UNIT SEPARATOR.

2.
public static boolean isBlank(String text) {
//        Pattern pattern = Pattern.compile("[\\s\\t]");
        Pattern pattern = Pattern.compile("\\s+");
        char[] chars = text.toCharArray();
        for(int i = 0; i < chars.length; i++) {
            String s = String.valueOf(chars[i]);
            Matcher re = pattern.matcher(s);
            boolean find = re.find();
            if(!find) {
                return false;
            }
        }

詳解 "\s+"

正則表達式中\(zhòng)s匹配任何空白字符，包括空格、制表符、換頁符等等, 等價于[ \f\n\r\t\v]

• \f -> 匹配一個換頁
• \n -> 匹配一個換行符
• \r -> 匹配一個回車符
• \t -> 匹配一個制表符
• \v -> 匹配一個垂直制表符