代码练习

byte b =127;//范围-128至127
        
        short s = 2;
        
        int j = 123;
        
        long l = 1234L;//后面标记L确定为long型
        
        int c = (int)1234l;//强制转换，显示转换
        
        long ll = b;
        
        float f = 123.45f;//需要在数字末尾加“f”标记
        
        double d =12345;
        
        f = (float)d;//强制转换，必须是相关数据类型才可以转换
        
        f = l;
        
        char v ='a';//单引号‘’引起来你的单个字符
        
        int a = v;
        
        System.out.println("a =" +a);
        
        char g = 98;
        
        System.out.println("g =" +g);//ASCII码
        
        //UTF-8
        
        boolean t = true;     //逻辑真，true和false都是小写
        
        t = false;//逻辑假