What is the best way to transfer files using Java?

I'm writing a code to upload files from the client to my server, and the performance is not as fast as I think

I am now executing the code segment of file transfer. I want to know how to speed up the transfer

Sorry, all codes:

InputStream fileItemInputStream ;
OutputStream saveFileStream;
int[] buffer;
while (fileItemInputStream.available() > 0) {
    buffer = Util.getBytesFromStream(fileItemInputStream);
    Util.writeIntArrToStream(saveFileStream,buffer);
}
saveFileStream.close();
fileItemInputStream.close();

Util method is as follows:

public static int[] getBytesFromStream(InputStream in,int size) throws IOException {
    int[] b = new int[size];
    int count = 0;
    while (count < size) {
        b[count++] = in.read();
    }
    return b;
}

And:

public static void writeIntArrToStream(OutputStream out,int[] arrToWrite) throws IOException {
    for (int i = 0; i < arrToWrite.length; i++) {
        out.write(arrToWrite[i]);
    }
}

Solution

Reading one byte at a time would be very inefficient You also rely on availability, which is rarely a good idea (if no bytes are currently available, 0 is returned, but more bytes may be available.)

This is the correct code for the copy stream:

public void copyStream(InputStream input,OutputStream output) throws IOException
{
    byte[] buffer = new byte[32*1024];
    int bytesRead;
    while ((bytesRead = input.read(buffer,buffer.length)) > 0)
    {
        output.write(buffer,bytesRead);
    }
}

(the caller should close both streams.)