Java FileChannel.write不完整
我正在使用Java FileChannel.write不完整,java,nio,filechannel,Java,Nio,Filechannel,我正在使用FileChannel将2MB数据写入一个文件 private void write(int numEntries, int entrySize) throws Exception { File dir = new File(iotestDir); dir.mkdirs(); File file = new File(dir, "data00001.dat"); file.delete(); file.createNewFil
FileChannel
将2MB数据写入一个文件
private void write(int numEntries, int entrySize)
throws Exception
{
File dir = new File(iotestDir);
dir.mkdirs();
File file = new File(dir, "data00001.dat");
file.delete();
file.createNewFile();
try {
FileChannel channel = new FileOutputStream(file).getChannel();
ByteBuffer[] bb = new ByteBuffer[numEntries];
for (int i = 0; i < numEntries; ++i) {
bb[i] = generator.generateRandomSlice(entrySize).toByteBuffer();
}
System.out.println(bb.length);
long position = channel.write(bb);
System.out.println(position);
Thread.sleep(10000);
channel.force(true);
channel.close();
}
catch (Exception e) {
file.delete();
e.printStackTrace();
throw e;
}
}
调用write(10001024)
时,它工作正常。写入1024000字节
我做错了什么?您假设
write()
应该传输整个缓冲区数组。实际上,它不必传输超过一个字节。这就是它返回计数的原因;这也是为什么Javadoc说它可以返回零,并谈论“实际写入的字节数”
你必须循环
# ls -al
total 1032
drwxrwxr-x 2 lingchuanhu lingchuanhu 4096 Mar 12 13:06 .
drwxrwxr-x 5 lingchuanhu lingchuanhu 4096 Mar 12 11:40 ..
-rw-rw-r-- 1 lingchuanhu lingchuanhu 1048576 Mar 12 13:06 data00001.dat