Gson Library在Directory中编写一个文件

Question

我需要帮助来理解Gson库的Jsonwriter选项。基本上，我可以从该位置读取文件。然后我将数据转换为Java List后修改了数据。我可以将修改后的json发送到ajax响应，一切正常。现在我想将这个修改过的json保存在指定的文件中。有一件事我想确保File被清除并用新的json值更新。

//Read File done
//converted to list
//List modified
//converting to Json 

String json = new Gson().toJson(myData);
System.out.println(json);

// Sent to ajax response and worked fine
// Now update file with new json...

//JsonWriter writer = new JsonWriter(new FileWriter(ctx.getRealPath("file.text")));


    FileWriter writer = new FileWriter(new File(ctx.getRealPath("file.txt")));
    writer.write(json);
    writer.flush();
    writer.close();

提前谢谢！

替代代码------

FileWriter fw = null;
                try {
                    fw = new FileWriter(new File(ctx.getRealPath("file.txt")));
                    BufferedWriter bw = new BufferedWriter(fw);
                    bw.write(json);
                    bw.flush();
                } catch (IOException e) {
                    e.printStackTrace();
                } finally {
                    try {
                        if (fw != null) {
                            fw.close();
                        }
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }