JAVA 转义字符串中的特殊字符

package test;

import java.util.regex.Matcher;

import java.util.regex.Pattern;

public class Test {

     public static void main(String[] args) {

        String str = "789##$";

        String regEx="[`~!@#$%^&*()+=|{}':;',\\[\\].<>/?~！@#￥%……&*（）——+|{}【】‘；：”“’。，、？]";

        Pattern p = Pattern.compile(regEx);

        Matcher m1 = p.matcher(str);

        if(m1.find()){

            CharSequence cs = str;

            int j =0;

            for(int i=0; i< cs.length(); i++){

                String temp = String.valueOf(cs.charAt(i));

                Matcher m2 = p.matcher(temp);

                if(m2.find()){

                    StringBuilder sb = new StringBuilder(str);

                    str = sb.insert(j, "\\").toString();

                    j++;

                }

                j++; //转义完成后str的长度增1

            }

            System.out.println(str);

        }

    }

}