java - java中比较两个字符串以忽略大小写和特殊字符？

Question

    String s1 = "Madam,I'm Adam";
    String s2 = "madam i m adam";
    String str = s1.replaceAll("-,' "," ");
    System.out.println(str.equalsIgnoreCase(s2));    //  false 

如何使 s1 和 s2 相等？

Answer 1

使用正则表达式过滤字符串，例如[^\\w\\d\\s] - 不是字符，不是数字，不是空格:

public static void main(String[] args) {
    String s1 = "Madam,I'm Adam";
    String s2 = "madam i m adam";
    System.out.printf("  -> %s\n", normalizedEquals(s1, s2));    //  false     
}

static String normalize(String s) {
    // here goes normalization
    return s.replaceAll("[^\\w\\d\\s]", " ");
}

static boolean normalizedEquals(String s1, String s2) {
    s1 = normalize(s1);
    s2 = normalize(s2);
    System.out.printf("  -> %s\n  -> %s\n", s1, s2);
    return s1.equalsIgnoreCase(s2);
}

输出:

-> Madam I m Adam
-> madam i m adam
-> true