Question

我正在使用此API来解析

中提供的维基百科转储

http://code.google.com/p/wikixmlj/

我正在使用我的API

Class wiki
{
  public void parseWiki()
  {

      PageCallbackHandler handler = new WikiPageCallbackHandler()
      WikiXMLSAXParser.parseWikipediaDump(filepath, handler )
   }

    }

Class WikiPageCallbackHandler implements PageCallbackHandler 
{
    //Override
    //This is the callback
   void process(WikiPage page)
   {
        String Text = page.GetText();
        //Write this text into a file
        .....
   }
}

问题出在所有回调完成之前我完成将其写入文件，应用程序正在终止，我没有得到所有回调。我想知道为什么会发生这种情况，有没有办法保留我的主线程，以便我得到所有的回调。另外，我怎么知道我是否收到了所有回调？

由于

Answer 1

您是否尝试在Oracle Docs使用'信号量' 以下是Semaphore的使用示例：

class wiki
{
    public void parseWiki(){
        // initialize Semaphore object
        Semaphore semaphore = new Semaphore(1); 
        //pass it to callback handler so it can release semaphore latter
        PageCallbackHandler handler = new WikiPageCallbackHandler(semaphore);
        //This is the async operation, right?
        WikiXMLSAXParser.parseWikipediaDump(filepath, handler );
        //wait until a permit is available (when semaphore.release() is called)
        semaphore.acquire(); //this throw InterruptedException, please handle it else where
    }
}

class WikiPageCallbackHandler implements PageCallbackHandler 
{
    private Semaphore semaphore;
    public WikiPageCallbackHandler(Semaphore semaphore){
        this.semaphore = semaphore;
    }
    //Override
    //This is the callback
    void process(WikiPage page)
    {
        try{
            String Text = page.GetText();
            //Write this text into a file
            .....
        }finally{
            semaphore.release();
        }
    }
}

应用程序在所有回调完成之前终止

1 个答案: