java - 如何解决未封闭字符类错误

Question

这是我的代码:

string.replaceAll("(?i)["+key+"]\\S*", "[blue]$0[blue]")

它抛出未封闭的角色类

Answer 1

使用组，不要忘记逃避其他选择:

import java.util.*;
import java.util.stream.*;
import java.util.regex.*;
 
class app
{
    public static void main (String[] args) throws java.lang.Exception
    {
        List<String> key = Arrays.asList("as","if","when","and","then");
        List<String> alternatives = key.stream()
            .map(Pattern::quote)
            .collect(Collectors.toList());
        String string = "AS?! When then";
        System.out.println( string.replaceAll("(?i)(?:"+String.join("|", alternatives)+")\\S*", "[blue]$0[blue]") );
    }
}

[**Java code demo**][1]

结果: [blue]AS?![blue] [blue]When[blue] [blue]then[blue]