我目前正在构建一个GSONFileWriter类。

public class GSONFileWriter {

private File jsonFile;

private final String json;

public GSONFileWriter(String json) {
    this.json = json;
}

public void generateJsonFileIfNotExists(String pathname) {
    try {
        jsonFile = new File(pathname);
        if (!jsonFile.exists()) {
            if (jsonFile.createNewFile()) {
                System.out.println("File successful created.");
            } else {
                System.out.println("Error: Building the file went wrong!");
                System.exit(1);
            }
        }
        fillJsonFile();
    } catch (Exception e) {
        System.err.println("Error: Building the file went wrong!");
    }
}

private void fillJsonFile() {
    try (PrintWriter writer = new PrintWriter(jsonFile, StandardCharsets.UTF_8)) {
        writer.append(json);
        writer.println();
    } catch (Exception e) {
        e.printStackTrace();
    }
}

}
在CLI类内部调用

Gson gson = new Gson();
            String json = gson.toJson(target);
            GSONFileWriter gsonFileWriter = new GSONFileWriter(json);
            gsonFileWriter.generateJsonFileIfNotExists("EmployeeData.json");

它创建并构建一个新的JSON文件，其中包含一个对象。

{"salary":34000.0,"name":"Hans","age":30,"id":"d40507a7-a802-4494-9a0c-5a97a0a4d0bf"}

然而问题是，每当我再次运行代码，旧文件被覆盖，并创建一个新的.我试图改变代码，使它添加一个新的对象到文件，而不是覆盖它.任何提示？