判断输入的数字

String str = "234电饭锅";
    //判断输入的为数字   
     Pattern pattern = Pattern.compile("[0-9]*"); 
      Matcher matcher = pattern .matcher(str); 
      if(matcher .matches() ){
           Toast.makeText(Main.this,"输入的是数字", Toast.LENGTH_SHORT).show();
      } 
    //判断输入的为字母
     Pattern pattern =Pattern.compile("[a-zA-Z]");
      Matcher matcher = pattern .matcher(str); 
      if(matcher .matches()){
           Toast.makeText(Main.this,"输入的是字母", Toast.LENGTH_SHORT).show();
     }
    //判断输入的为汉字
     Pattern pattern =Pattern.compile("[\u4e00-\u9fa5]");
      Matcher matcher = pattern .matcher(str); 
      if(matcher .matches()){
           Toast.makeText(Main.this,"输入的是汉字", Toast.LENGTH_SHORT).show();
      }