将一个文件中的汉字写入另一个文件

我有一个里面有汉字文本的文件，我想将这些文本复制到另一个文件中。但文件输出与中文字符混乱。请注意，在我的代码中，我已经使用“UTF8”作为我的编码：

BufferedReader br = new BufferedReader(new FileReader(inputXml));
StringBuilder sb = new StringBuilder();
String line = br.readLine();
while (line != null) {
sb.append(line);
sb.append("\n");
line = br.readLine();
}
String everythingUpdate = sb.toString();

Writer out = new BufferedWriter(new OutputStreamWriter(
        new FileOutputStream(outputXml), "UTF8"));

out.write("");
out.write(everythingUpdate);
out.flush();
out.close();

@hyde 的答案是有效的，但我有两个额外的注释，我将在下面的代码中指出。

当然，您可以根据自己的需要重新组织代码

// Try with resource is used here to guarantee that the IO resources are properly closed
// Your code does not do that properly, the input part is not closed at all
// the output an in case of an exception, will not be closed as well
try (BufferedReader reader = new BufferedReader(new InputStreamReader(new FileInputStream(inputXML), "UTF-8"));
    PrintWriter out = new PrintWriter(new OutputStreamWriter(new FileOutputStream(outputXML), "UTF8"))) {
    String line = reader.readLine();

    while (line != null) {
    out.println("");
    out.println(line);

    // It is highly recommended to use the line separator and other such
    // properties according to your host, so using System.getProperty("line.separator")
    // will guarantee that you are using the proper line separator for your host
    out.println(System.getProperty("line.separator"));
    line = reader.readLine();
    }
} catch (IOException e) {
  e.printStackTrace();
}