文件复制通道
fromFile.exists()
fromFile.isFile()
// 复制文件
??????????????? File newToFile = new File(toPath);
??????????????? newToFile.createNewFile();
??????????????? FileInputStream inFile = new FileInputStream(fromFile);
??????????????? FileOutputStream outFile = new FileOutputStream(newToFile);
??????????????? FileChannel inChannel = inFile.getChannel();
??????????????? FileChannel outChannel = outFile.getChannel();
??????????????? long bytesWritten = 0;
??????????????? long byteCount = inChannel.size();
??????????????? while (bytesWritten < byteCount) {
??????????????????? bytesWritten += inChannel.transferTo(bytesWritten,byteCount - bytesWritten, outChannel);
??????????????? }
??????????????? inFile.close();
??????????????? outFile.close();
?