java - 正则表达式查找字符串中的数字

Question

我正在使用 removeNumbers 通过正则表达式删除给定字符串中的所有数字
“(^|)\\d+($|(\\d+)+($|)|)”

代码如下:

public class Regex {    
  private static String removeNumbers(String s) {
     s = s.trim();
     s = s.replaceAll(" +", " ");
     s = s.replaceAll("(^| )\\d+($|( \\d+)+($| )| )", " ");
     return s.trim();
  }

  public static void main(String[] args) {
     String[] tests = new String[] {"123", "123 456 stack 789", "123 456 789 101112 131415 161718 192021", "stack 123 456 overflow 789 com", "stack 123 456 overflow 789", "123stack 456", "123 stack456overflow", "123 stack456", "123! @456#567"};
     for (int i = 0; i < tests.length; i++) {
        String test = tests[i];
        System.out.println("\"" + test + "\" => \"" + removeNumbers(test) + "\"");
     }  
  }    
}

输出:

"123" => ""
" 123 " => ""
"123 456 stack 789" => "stack"
"123 456 789 101112 131415 161718 192021" => ""
"stack 123 456 overflow 789 com" => "stack overflow com"
"stack 123 456 overflow 789" => "stack overflow"
"123stack 456" => "123stack"
"123 stack456overflow" => "stack456overflow"
"123 stack456" => "stack456"
"123! @456#567" => "123! @456#567"

有没有更好的方法来做到这一点？

编辑:

正如@mbomb007 在他之前的回答中所建议的那样，正则表达式 "( |^)[\\d ]+( |$)" 也适用:

private static String removeNumbers(String s) {
   s = s.trim();
   s = s.replaceAll(" +", " ");
   s = s.replaceAll("( |^)[\\d ]+( |$)", " ");
   return s.trim();
}

Answer 1

AFAIU，你可以这样做:

private static String removeNumbers(String s) {
    return s.replaceAll("\\b\\d+\\b", "").replaceAll(" +", " ").trim();
}

\b\d+\b 匹配一个或多个组成单词的数字。

编辑:

由于模式不能匹配字符串中的数字，例如 "123!@456#567"，因此可以结合使用积极的后视和先行条件:

private static String removeNumbers(String s) {
    return s.replaceAll("(?<= |^)\\d+(?= |$)", " ").replaceAll(" +", " ").trim();
}