//【全为英文】返回true  否则false  
        boolean result1 = str.matches("[a-zA-Z]+");
        //【全为数字】返回true
        Boolean result6 = str.matches("[0-9]+");
        //【除英文和数字外无其他字符(只有英文数字的字符串)】返回true 否则false
        boolean result2 = str.matches("[a-zA-Z0-9]+");
        //【含有英文】true
        String regex1 = ".*[a-zA-z].*";  
        boolean result3 = str.matches(regex1);
        //【含有数字】true
        String regex2 = ".*[0-9].*";  
        boolean result4 = str.matches(regex2);
        //判断是否为纯中文，不是返回false
        String regex3 = "[\\u4e00-\\u9fa5]+";
        boolean result5 = str.matches(regex3);