Java数据类型转换

byte b = 0;
		int i = 258;
		double d = 323.942;
		
		b = (byte) i;			//byte 转 int 取int%256的值,取余数
		System.out.println(b);
		
		i = (int) d;			//double 转 int 直接舍弃小数部分,不会有四舍五入现象
		System.out.println(i);
		
		b = (byte) d;
		System.out.println(b);	//double 转 byte 取double%256的值,取余数
		
		System.out.println((byte)d%256);	//是这种操作
		
		//表达式类型自动提升
		float f = 30000.14f;
		float fResult = f*f;		//类型没有自动提升
		double dResult = f*d;		//类型自动提升至double
		
		i = b+b;					//类型自动提升至int
		
		f = f * b;					//类型提升至了float
		
		short s = 33;
		
		char c = 64;
		
		i = s+s;					//类型自动提升
		
		i = c+c;					//类型自动提升
		
		System.out.println(fResult);
		
		System.out.println(-9/-3);