sizeof(i); //值为4,等价于sizeof(int) sizeof i; //值为4 sizeof(2); //值为4,等价于sizeof(int),因为2的类型为int sizeof(2 + 3.14); //值为8,等价于sizeof(double),因为此表达式的结果的类型为double char ary[sizeof(int) * 10]; //OK,编译无误 1. 2. 3. 4. 5. 6. 7. 8...
而在C/C++中需要sizeof是因为移植,不同的数据类型在不同的机器上大小可能不同,程序员必须知道对应的数据类型大小。 详细介绍 Java数据类型 Java基本数据类型 int 32bit short 16bit long 64bit byte 8bit char 16bit float 32bit double 64bit boolean 1bit Java基本数据类型封装类 Integer // 4 byte Short ...
根据http://docs.oracle.com/javase/tutorial/java/nutsandbolts/datatypes.html官方文档的描述: boolean: The boolean data type has only two possible values: true and false. Use this data type for simple flags that track true/false conditions. This data type represents one bit of information, but ...
int 32bit short 16bit long 64bit byte 8bit char 16bit float 32bit double 64bit boolean 1bit,This data type represents one bit of information, but its "size" isn't something that's precisely defined.(ref) Java基本数据类型大小 [java]view plaincopy print? privatestaticvoid calSize() { Sy...
boolean:1 byte,尽管Java语言规范里面boolean是一个bit; byte:1 byte; char:2 bytes; short:2 bytes; int:4 bytes; float:4 bytes; long:8 bytes; double:8 bytes。 二,引用类型: 4 bytes,即使是null值也是如此。 三,空的普通对象(无任何属性,如new Object(),不是null对象): ...
SizeOf.setMinSizeToLog(1024); //min object size to log in bytes SizeOf.setLogOutputStream(new FileOutputStream("<your log file>")); Use the humanReadable() method to get the object size in byte, kilo or mega (if you need giga your in trouble guy!): ...
Java中的Sizeof Java有类似于C语言中sizeof()的操作器吗？ 表面答案是Java没有提供任何类似于C语言的sizeof()的操作器。但是，我们应该想想为什么Java程序员偶尔也需要它。 C语言程序员自己管理大多数的数据结构存储分配，并且sizeof()不负责了解分配的存储块的尺寸大小。C存储分配器如malloc()，只要涉及到...
java中的sizeof(Java sizeof) Sizeof in Java Does Java have an operator similar to sizeof () in the C language? The answer is that Java does not provide any sizeof - (C) - like operator. But we should think about why Java programmers need it occasionally. The C language programmer ma...
Minimum object size is 16 bytes for modern 64-bit JDK since the object has 12-byte header, padded to a multiple of 8 bytes. In 32-bit JDK, the overhead is 8 bytes, padded to a multiple of 4 bytes. References have a typical size of 4 bytes on 32-bit platforms and on 64-bits ...
assertEquals("12 KB", FileUtils.byteCountToDisplaySize(size)); }Copy 6. How to Get the Size of a File in MB, KB & GB in Java To get the size of a file in megabytes (MB), kilobytes (KB), and gigabytes (GB) in Java, we need first to understand the relation between these units...