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File file = new File("D:/201709201336160.05V")
getFileSize(file)
}
/**
* 获取文件大小
* @param file
*/
public static void getFileSize(File file) {
FileInputStream fis = null
try {
if(file.exists() &&file.isFile()){
String fileName = file.getName()
fis = new FileInputStream(file)
System.out.println("文件"+fileName+"的大小是："+fis.available()+"\n")
}
} catch (Exception e) {
e.printStackTrace()
}finally{
if(null!=fis){
try {
fis.close()
} catch (IOException e) {
e.printStackTrace()
}
}
}
}
这个可以判断大小 输出的是byte 你转化一下MB就行了
public static void getFileSize(String path){//传入文件路径
File file = new File(path)
//测试此文件是否存在
if(file.exists()){
//如果是文件夹
//这里只检测了文件夹中第一层 如果有需要 可以继续递归检测
if(file.isDirectory()){
int size = 0
for(File zf : file.listFiles()){
if(zf.isDirectory()) continue
size += zf.length()
}
System.out.println("文件夹 "+file.getName()+" Size: "+(size/1024f)+"kb")
}else{
System.out.println(file.getName()+" Size: "+(file.length()/1024f)+"kb")
}
//如果文件不存在
}else{
System.out.println("此文件不存在")
}
}
import java.net.*import java.io.*
public class URLConnectionDemo{
public static void main(String[] args)throws Exception{
URL url = new URL("http://www.scp.edu.cn/pantoschoolzz/BG/Bord/Message/DownloadMessageAttachment.aspx?ID=215")
URLConnection uc = url.openConnection()
String fileName = uc.getHeaderField(6)
fileName = URLDecoder.decode(fileName.substring(fileName.indexOf("filename=")+9),"UTF-8")
System.out.println("文件名为："+fileName)
System.out.println("文件大小："+(uc.getContentLength()/1024)+"KB")
String path = "D:"+File.separator+fileName
FileOutputStream os = new FileOutputStream(path)
InputStream is = uc.getInputStream()
byte[] b = new byte[1024]
int len = 0
while((len=is.read(b))!=-1){
os.write(b,0,len)
}
os.close()
is.close()
System.out.println("下载成功,文件保存在："+path)
}
}
