java - 如何打印带有缺少反斜杠的unicode字符的字符串？

Question

我有一个字符串如下:

this is the string u00c5 with missing slash before unicode characters

它具有 unicode 字符代码，但缺少“u”之前的所有反斜杠。如何正确打印这个字符串？

我做了什么？

我尝试使用以下代码在不完整的 unicode 部分之前添加反斜杠。但是，replaceAll 中不允许使用 "\u$1"。

public String sanitizeUnicodeQuirk(String input) {
    try {
        // String processedInput = input.replaceAll("[uU]([0123456789abcdefABCDEF]{4})", String.valueOf(Integer.parseInt("$1", 16)));    // $1 is taken literally which makes valuOf and parseInt useless
        String processedInput = input.replaceAll("[uU]([0123456789abcdefABCDEF]{4})", "\\\\u$1");    // Cannot make "\u$1"
        String newInput = new String(processedInput.getBytes(), "UTF-8");
        return newInput;
    } catch (UnsupportedEncodingException e) {
        e.printStackTrace();
    }

    return input;
}

Answer 1

哎呀。使用 @AlastairMcCormack 在评论中提供的可能重复链接进行概念证明:

public class Test {
    public static void main(String[] args) {
        String input = "this is the string u0075u0031u0032u0033u0034 with missing slash before unicode characters";
        System.out.println("Original input: " + input);
        Pattern pattern = java.util.regex.Pattern.compile("[uU][0-9a-fA-F]{4}");
        Matcher matcher = pattern.matcher(input);
        StringBuilder builder = new StringBuilder();
        int lastIndex = 0;
        while (matcher.find()) {
               String codePoint = matcher.group().substring(1);
               System.out.println("Found code point: " + codePoint);
               Character charSymbol = (char) Integer.parseInt(codePoint, 16);
               builder.append(input.substring(lastIndex, matcher.start()) + charSymbol);
               lastIndex = matcher.end();
        }
        builder.append(input.substring(lastIndex));
        System.out.println("Modded input: " + builder.toString());
    }
}

产量:

Original input: this is the string u0075u0031u0032u0033u0034 with missing slash before unicode characters
Found code point: 0075
Found code point: 0031
Found code point: 0032
Found code point: 0033
Found code point: 0034
Modded input: this is the string u1234 with missing slash before unicode characters

代码点被编码为字符串确实有意义，并且使用正则表达式进行任何简单的清理都无法解决这个问题。这不太漂亮，所以如果有人有其他方法，我也会很高兴。