Java 调用 replaceAll()方法报错:java.lang.IllegalArgumentException: Illegal group reference

处理办法

用JDK提供的方法，对特殊字符进行处理

replacement = java.util.regex.Matcher.quoteReplacement(replacement);

    public static void main(String[] args) {
        String regex = "str";
        String replacement = "a$bc$d";
        replacement = java.util.regex.Matcher.quoteReplacement(replacement);
        String str = "test str replace.";
        String str1 = str.replaceAll(regex, replacement);
        System.out.println(str1);
    }