Java通过Http请求下载文本附件到本地

 

//首先通过socket获取下载流

InputStream is=socket.getInputStream();

int lengt = 1024;//根据实际情况获得
final ByteArrayOutputStream baos = readLengthData(is,length);//读取未经解压的数据流

final ByteArrayInputStream bais = new ByteArrayInputStream(baos.toByteArray());
GZIPInputStream in = new GZIPInputStream(bais);//将未解压的数据流放入GZIP流进行解压
final BufferedInputStream bis = new BufferedInputStream(is);//输出解压后的字符流
final ByteArrayOutputStream newbaos = new ByteArrayOutputStream();

while(bis.available() > 0) {
   newbaos.write(bis.read());//转换为字节
}

byte[] content = newbaos.toByteArray();
FileOutputStream outf= new FileOutputStream(file,append);
        	
//          ObjectOutputStream oos = new ObjectOutputStream(outf);//用objectouput可能会在文件头多写几个字节码
//          oos.write(content);
//          oos.close();
            
  BufferedOutputStream bufferout= new BufferedOutputStream(outf);
  bufferout.write(content);
  bufferout.flush();
  bufferout.close();

private final ByteArrayOutputStream readLengthData(final InputStream is, final int length) throws IOException {
  final BufferedInputStream bis = new BufferedInputStream(is);
  final ByteArrayOutputStream baos = new ByteArrayOutputStream();
  int read = 0;
  int total = length;
  while(read < total) {
   total -= read;
   byte[] result = new byte[total];
   read = bis.read(result);
   baos.write(result, 0, read);
  }
  while(bis.available() > 0) {
   int num = bis.read();
   if(num == 255 || num == -1){
    continue;
   }
   baos.write(bis.read());
  }
  return baos;
 }