public static void copyFlie(File srcFile ,File destFile) throws IOException {

if(!srcFile.exists()) {

throw new IllegalArgumentException("目標(biāo)文件："+srcFile +" 不存在");

}

if(!srcFile.isFile()) {

throw new IllegalArgumentException(srcFile+" 不是文件");

}

FileInputStream in = new FileInputStream(srcFile);

FileOutputStream out = new FileOutputStream(destFile);

byte[] buf = new byte[8*1024];

int b;

while((b = in.read(buf, 0, buf.length))!=-1) {

out.write(buf, 0, b);

}

in.close();

out.close();

}

/**

* 進(jìn)行文件的拷貝，利用帶緩存的字節(jié)流

*?

* @param srcFile

* @param destFile

*/

public static void copyByBuffer(File srcFile ,File destFile) throws IOException{

if(!srcFile.exists()) {

throw new IllegalArgumentException("目標(biāo)文件："+srcFile +" 不存在");

}

if(!srcFile.isFile()) {

throw new IllegalArgumentException(srcFile+" 不是文件");

}

BufferedInputStream bis = new BufferedInputStream(new FileInputStream(srcFile));

BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream(destFile));

byte[] buf = new byte[8*102];

int c;

while((c=bis.read(buf , 0 ,buf.length))!=-1) {

bos.write(buf,0,c);

bos.flush();//刷新緩沖區(qū)

}

bis.close();

bos.close();

}

對(duì)1.09G文件的操作，進(jìn)行五組數(shù)據(jù)對(duì)比，copyFlie平均用時(shí)14093，copyByBuffer當(dāng)flush在循環(huán)外平均用時(shí)13971

由于每次讀取時(shí)間不確定，有的copyfile快于copybybuffere，有的相反，所以感覺(jué)速度不相上下。當(dāng)copybybuffere采用單字節(jié)的時(shí)候，時(shí)間不可想象，太長(zhǎng)了，如果flush在循環(huán)內(nèi)部時(shí)間也會(huì)過(guò)長(zhǎng)，沒(méi)有做對(duì)比