java ---正则表达式

package sad;

import java.util.Scanner;
//正則表達式是字符串類型
import javax.management.loading.PrivateClassLoader;
public class ers {
    public static void main(String[] args)
    {   
         System.out.println("請輸入您要操作的字符串：");
         Scanner sc = new Scanner(System.in);
         String str1 = sc.next();
         Factory.switches(str1);
    }
    }
class Factory
{  
    static int chance;
     static void switches(String str1)
    {
    Scanner sc = new Scanner(System.in);
    System.out.println("请输入您要进行的操作：");
    System.out.print("\n\n");
    System.out.println("1.普通方法確定字符串是否全由數字構成");
    System.out.println("2.正則表達式確定字符串是否全由數字構成");
    System.out.println("3.刪除字符串中的所有數字");
    System.out.println("4:驗證郵箱格式是否正確");
    chance = sc.nextInt();
    switch(chance)
    {
    case 1:
        new NormalBoolean(str1);
        break;
    case 2:
        new ZhengzeBoolean(str1);
        break;
    case 3:
        new ExchangeNum(str1);
        break;
    case 4:
        new TestMail(str1);
        break;
    default:
        break;
    }
    }
}
class NormalBoolean
{
    NormalBoolean(String str) //常规方法
    {   
        char[] arr = str.toCharArray();
        for(int i=0;i<arr.length;i++)
        {
            if(arr[i]<'0'||arr[i]>'9')
            {
                System.out.println("不是全由数字构成");
            }
        }
        System.out.println("是全由数字构成");
        }
    
}
class ZhengzeBoolean    //正则表达式
{  
    public ZhengzeBoolean(String str1)
    {
    if(str1.matches("\\d+"))
    {
        System.out.println("正则验证是由数字构成");
    }
    else
    {
        System.out.println("正则验证不是由数字构成");
    }
}
}
class ExchangeNum     //刪除字符串中的數字
{
    public ExchangeNum(String str) {
        // TODO Auto-generated constructor stub
        exchange(str);
    }
    private void exchange(String str)
    {
        String regex = "[0-9]+";
        //String regex = "\\d++";
        System.out.println(str.replaceAll(regex,"*"));   //可以將數字替換成其他字符
    }
}
class TestMail           //驗證郵箱格式是否正確       *****@****.****
{
    public TestMail(String Str)
    {
        Mail(Str);
    }
    private void Mail(String Str)
    {
        String regex = "\\w+@\\w+\\.\\w+";
        String regex1= "[1]";
        System.out.println(Str.matches(regex1));
    }
}