Java -跨平台桌面(？)节省时间

Question

目前，我有以下几点：

            if(Menu.menuChoice == 0){
                if(Menu.menuChoice == 0){
                    if(Library.ManualList.size() > 0){
                        boolean saveYesNo = Console.readYesNo("\nThe manualKeeper app is able to save your current library to a '.txt' \nfile in your workspace directory.\n\nWould you like to save the current library? (Y/N):\n");
                        if(saveYesNo==true){
                            try {
                                File file = new File("Library.txt");
                                System.getProperty("user.home");

                                file.createNewFile();
                                FileWriter fw = new FileWriter(file, true);
                                PrintWriter pw = new PrintWriter(fw);

                                for (int i = 0; i < Library.ManualList.size(); i++){
                                    pw.println("\n-------------------- Index Number: " + i + " --------------------");
                                    pw.println(Library.ManualList.get(i).displayManual());
                                    pw.println("---------------------------------------------------------");
                                }
                                pw.close();
                                System.out.println("\n\n--------------------------------------------------------------------------");
                                System.out.println("\n                              Library saved!\n");
                                System.out.println("--------------------------------------------------------------------------\n");
                                break exit;
                            } catch (IOException e) {
                                System.out.println("Error! Library unable to save.");
                            }

                        }
                            else if(saveYesNo==false){
                                System.out.println("\n\n--------------------------------------------------------------------------");
                                System.out.println("\n                              Library not saved!\n");
                                System.out.println("--------------------------------------------------------------------------\n");
                                break exit;
                        }
                        Menu.displayMenu();
                    }else if(Library.ManualList.isEmpty()){ 
                        Menu.displayMenu();
                    }
                }
            }   

它将一个文本文件保存在Eclipse的工作区目录中，类文件位于该目录中。但是，当我将这个项目导出到一个".jar“文件时，我希望将文本文件保存在与jar文件或桌面文件相同的dir中。然而，我读过关于"User.home“的文章，因为我对编程还不熟悉，所以我还没能让它开始工作。有谁知道我怎么做到的吗？

编辑

更新代码：

            if(Menu.menuChoice == 0){
                if(Menu.menuChoice == 0){
                    if(Library.ManualList.size() > 0){
                        boolean saveYesNo = Console.readYesNo("\nThe manualKeeper app is able to save your current library to a '.txt' \nfile in your workspace directory.\n\nWould you like to save the current library? (Y/N):\n");
                        if(saveYesNo==true){
                            try {
                                String path = System.getProperty("user.dir") + File.separator + "Library.txt";
                                File file = new File(path);
                                file.createNewFile();
                                FileWriter fw = new FileWriter(file, true);
                                PrintWriter pw = new PrintWriter(fw);

                                for (int i = 0; i < Library.ManualList.size(); i++){
                                    pw.println("\n-------------------- Index Number: " + i + " --------------------");
                                    pw.println(Library.ManualList.get(i).displayManual());
                                    pw.println("---------------------------------------------------------");
                                }
                                pw.close();
                                System.out.println("\n\n--------------------------------------------------------------------------");
                                System.out.println("\n                              Library saved!\n");
                                System.out.println("--------------------------------------------------------------------------\n");
                                break exit;
                            } catch (IOException e) {
                                System.out.println("Error! Library unable to save.");
                            }

                        }
                            else if(saveYesNo==false){
                                System.out.println("\n\n--------------------------------------------------------------------------");
                                System.out.println("\n                              Library not saved!\n");
                                System.out.println("--------------------------------------------------------------------------\n");
                                break exit;
                        }
                        Menu.displayMenu();
                    }else if(Library.ManualList.isEmpty()){ 
                        Menu.displayMenu();
                    }
                }
            }   

Answer 1

以下几点应该能起作用。

String path = System.getProperty("user.dir") + File.separator + "foo.txt";
File customfile = new File(path);

这个

String path = System.getProperty("user.dir") + File.separator + "foo.txt";

获取用户所在的当前目录。

System.getProperty("user.dir")

获取文件分隔符。

File.separator

最后，将使用的文本文件命名为

foo.txt。

在那之后,

File customfile = new File(path);

使用刚才创建的path变量创建新文件，该变量保存文件的放置位置。