nio 拷贝

public static boolean copyFile(String srcFileName, String destPath, boolean forceReplace) {
if (!isValidEntityFile(srcFileName) || !isValidParam(destPath)) {
throw new IllegalArgumentException("Parameters are invalid.");
}
File destDir = new File(destPath);
if (!isValidEntityDirectory(destDir)) {
destDir.mkdirs();
}
File srcFile = new File(srcFileName);
String destFileName = destPath + File.separator + srcFile.getName();
File destFile = new File(destFileName);
if (forceReplace && isValidEntityFile(destFile)) {
destFile.delete();
}
FileInputStream fileInput = null;
FileOutputStream fileOutput = null;
try {
fileInput = new FileInputStream(srcFileName);
fileOutput = new FileOutputStream(destFile);
// 获取输入输出通道
FileChannel inputChannel = fileInput.getChannel();
FileChannel outputChannel = fileOutput.getChannel();
// 创建缓冲区
ByteBuffer buffer = ByteBuffer.allocate(1024 * 4);
while (true) {
// clear方法重设缓冲区，使它可以接受读入的数据
buffer.clear();
// 从输入通道中将数据读到缓冲区
int r = inputChannel.read(buffer);
// read方法返回读取的字节数，可能为零，如果该通道已到达流的末尾，则返回-1
if (r == -1) {
break;
}
// flip方法让缓冲区可以将新读入的数据写入另一个通道
buffer.flip();
// 从输出通道中将数据写入缓冲区
outputChannel.write(buffer);
}
} catch (Exception ex) {
logger.error("FileUtil.copyFile() Exception", ex);
return false;
} finally {
Util.closeStream(fileInput, fileOutput);
}
return true;
}