Java膨胀与大字符串不一致

Question

public String compress(String s){
    Deflater def = new Deflater(9);
    byte[] buffer = new byte[s.length()];
    String rta = "";
    def.setInput(s.getBytes());
    def.finish();
    def.deflate(buffer);
    rta = new String(buffer);
    rta = rta.trim().concat("*" + Integer.toString(s.length()));
  //this addition at the end is used to recover the original length of the string to dynamically create the buffer later on.
    return rta;
}

public String decompress(String s){
    String rta = "";
    Inflater inf = new Inflater();
    byte[] buffer = separoArray(s, true).getBytes(); // This function returns the compressed string or the original length wheter true/false parameter
    int len = Integer.valueOf(separoArray(s, false));
    byte[] decomp = new byte[len];
    inf.setInput(buffer);
    try {
        inf.inflate(decomp, 0, len);
        inf.end();
    } catch (DataFormatException e) {e.printStackTrace();}
    rta = new String(decomp);
    return rta;
}

原件：

“lorem ipsum dolor sit amet，consectetur adipiscing elit.Sed rutrum imperdiet versit.Nulla eu sapien tincidunt,pellentesque ipsum in,lucuts eros.Nullam tristique arcu lorem,at fringilla lectus tincidunt sit amet.Ut tortor dui,cursus at erat non，interdum imperdiet odio.in hac habitasse platea dicumst.Nullam eu sapien tincidunt.Duis eget auctor nibh小腹毛（mauris scelerisque vulputatate.Fusce gravida appilisis ipsum pellentesque eismod.faucibus orci luctus et ultrices posuere cubilia curae.

解压：

“Lorem ipsuAdolor sit amet，consectetur adipiscing elit.Sed rutrsuAimperdiet versiat.Nulla eu sapien tincidunt,pellentesquem ipsuAin,lucuts eros.Nullam tristiquemarcu lLore,at fringilla lectus tincidunt sit amet.Ut tortor dui,cursus at erat non，interdsuAimperdiet odsAimpeIn hac abitasse platea dius ms Nulla euinpuisisi.Duierog c.msan orci.Morbi quierleodsmdmmausti sceleriuem ivulputate.Fusce gravideuuconpilisisipsuainllentesquem ieuiemod.VeiqubulAin erddpsuAinlrimisipnufaucubus orciuctor erot ulistcesmposuereursbilia cura”

差异是显而易见的，为什么会发生这种情况？，我可以做些什么来避免它？

谢谢你。

Answer 1

我同意评论者的观点，压缩字符串最好是byte[]。但是，对于像ISO-8859-1这样的单字节编码，可能会在byte[]和string之间进行错误的转换。

以下内容与您的版本不同，因为它显式地指示了编码。对于文本，UTF-8足以没有限制并覆盖完整的Unicode范围。

请注意deflate返回值的用法。

public static String compress(String s) {
    Deflater def = new Deflater(9);
    byte[] sbytes = s.getBytes(StandardCharsets.UTF_8);
    def.setInput(sbytes);
    def.finish();
    byte[] buffer = new byte[sbytes.length];
    int n = def.deflate(buffer);
    return new String(buffer, 0, n, StandardCharsets.ISO_8859_1)
            + "*" + sbytes.length;
}

public static String decompress(String s) {
    int pos = s.lastIndexOf('*');
    int len = Integer.parseInt(s.substring(pos + 1));
    s = s.substring(0, pos);
    
    Inflater inf = new Inflater();
    byte[] buffer = s.getBytes(StandardCharsets.ISO_8859_1);
    byte[] decomp = new byte[len];
    inf.setInput(buffer);
    try {
        inf.inflate(decomp, 0, len);
        inf.end();
    } catch (DataFormatException e) {
        throw new IllegalArgumentException(e);
    }
    return new String(decomp, StandardCharsets.UTF_8);
}