2016-04-09 68 views
-2

我想知道如何使它成爲我的程序創建一個文件,如果它尚未找到它?如何避免FileNotFoundException?

public void load() throws Exception { 
    try 
     { 
     File log = new File(FILE_NAME); //opens the file 
     FileInputStream fileIn = new FileInputStream(log); 
     ObjectInputStream in = new ObjectInputStream(fileIn); //de-serializes 
     videosList = (ArrayList)in.readObject(); // de-serializes 
     in.close(); //closes the file 
     fileIn.close(); 
     } catch(Exception i) 
     { 
     i.printStackTrace(); 
     } 

這是我收到的錯誤:

java.io.FileNotFoundException: Users/hanaezz/Desktop/output.ser (No such file or directory) 
    at java.io.FileInputStream.open0(Native Method) 
    at java.io.FileInputStream.open(FileInputStream.java:195) 
    at java.io.FileInputStream.<init>(FileInputStream.java:138) 
    at videostore.BinaryFile.load(BinaryFile.java:31) 
    at videostore.VideoStore.<init>(VideoStore.java:33) 
    at videostore.VideoStore$6.run(VideoStore.java:430) 
    at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:311) 
    at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:756) 
    at java.awt.EventQueue.access$500(EventQueue.java:97) 
    at java.awt.EventQueue$3.run(EventQueue.java:709) 
    at java.awt.EventQueue$3.run(EventQueue.java:703) 
    at java.security.AccessController.doPrivileged(Native Method) 
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:76) 
    at java.awt.EventQueue.dispatchEvent(EventQueue.java:726) 
    at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:201) 
    at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116) 
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105) 
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101) 
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93) 
    at java.awt.EventDispatchThread.run(EventDispatchThread.java:82) 

所有多餘的東西存在,因爲我的程序也是一個GUI程序。然後我也有一個方法,它應該寫我的對象到一個文件...

public void writeToFile() throws Exception{ 
     FileOutputStream outputStream = new FileOutputStream(FILE_NAME); 
     ObjectOutputStream oos = new ObjectOutputStream(outputStream); 
     oos.writeObject(videosList); 
     oos.close(); 
     outputStream.close(); 
     } 

這會引發相同的異常。我怎樣才能避免這種情況?我不知道如何修改FIS/OIS來創建文件,如果他們沒有找到它..或者我認爲它會更有效率的FOS/OOS做到這一點呢?

+2

錯誤,請不要試圖打開一個不存在的文件?在這種情況下,你似乎缺少文件名中的前導'/'。 – EJP

+1

可能重複[檢查文件是否存在java](http://stackoverflow.com/questions/1237235/check-file-exists-java) – Ducaz035

+0

@ Ducaz035絕對不是。這是關於附加到現有文件。 – EJP

回答

1
Users/... 

您錯過了文件名中的前導碼/。所以你不能創建它,所以你不能讀它。

+0

你能否請你用更多的工作代碼來詳細說明你的答案 –

+0

@Suganthan你在開玩笑吧?你不知道如何添加一個前導'/'到文件名? – EJP

+0

但它不是有用戶代碼正確..? –