布爾總是返回true

Question

我目前正在學習Java。我正在製作一個程序來獲取給定URL的html代碼，然後將代碼保存爲* .html。在代碼的最後，我試圖打印一條消息，確定該文件是否已保存。

我的問題是，確定文件是否已保存的布爾總是返回true。

這裏是我的代碼：

public class URLClient { 
protected URLConnection connection; 

public static void main(String[] args){ 
    URLClient client = new URLClient(); 
    Scanner input = new Scanner(System.in); 
    String urlInput; 
    String fileName; 

    System.out.print("Please enter the URL of the web page you would like to download: "); 
    urlInput = input.next(); 

    System.out.println("Save file As: "); 
    fileName = input.next(); 


    String webPage = client.getDocumentAt(urlInput); 
    System.out.println(webPage); 
    writeToFile(webPage, fileName); 

} 

public String getDocumentAt (String urlString){ 
    StringBuffer document = new StringBuffer(); 

    try{ 
     URL url = new URL(urlString); 
     URLConnection conn = url.openConnection(); 
     BufferedReader reader = new BufferedReader(new InputStreamReader(conn.getInputStream())); 

     String line = null; 
     while ((line = reader.readLine()) != null) 
      document.append(line + "\n"); 
     reader.close(); 
    }catch (MalformedURLException e){ 
     System.out.println("Unable to connect to URL: " + urlString); 
    }catch (IOException e){ 
     System.out.println("IOException when connectin to URL: " + urlString); 
    } 

    return document.toString(); 
} 

public static void writeToFile(String content, String fileName){ 
    boolean saved = false; 

    try{ 
     OutputStream outputStream = new FileOutputStream(new File(fileName)); 
     BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(outputStream)); 

     try{ 
      writer.write(content); 
        boolean saved = true; 
     } finally { 
      writer.close(); 
     } 
    } catch (IOException e){ 
     System.out.println("Caught exception while processing file: " + e.getMessage()); 
    } 

    if (saved) 
     System.out.print("Successfully saved " + fileName + ".html"); 

} 

}

布爾被稱爲 「拯救」，是在將writeToFile（）方法。

任何幫助，將不勝感激:)

Answer 1

try { 
    writer.write(content); 
    saved = true; // no need to initialize again 
} finally { 
    writer.close(); 
} 

Answer 2

那麼你需要了解本地和全局變量的概念。您已經使用相同的數據類型初始化了兩次相同的變量名稱。我已經相應地爲您更改了代碼。

public static void writeToFile(String content, String fileName){ 
boolean saved = false; 

try{ 
    OutputStream outputStream = new FileOutputStream(new File(fileName)); 
    BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(outputStream)); 

    try{ 
     writer.write(content); 
     saved = true; 
    } finally { 
     writer.close(); 
    } 
} catch (IOException e){ 
    System.out.println("Caught exception while processing file: " + e.getMessage()); 
} 
if (saved) 
    System.out.print("Successfully saved " + fileName + ".html"); 
}