Android Log.X不打印堆棧跟蹤

Question

e.printStackTrace（）工作正常（即打印我的堆棧跟蹤到stderr）但Log.X根本無法打印堆棧跟蹤。

例如：

} catch (IOException e) { 
    Log.e("Network", "Exception", e); 
    e.printStackTrace(); 
} 

輸出：

08-31 03:46:21.992: W/Network(13238): Exception 
08-31 03:46:22.092: W/System.err(13238): java.net.UnknownHostException: Unable to resolve host "...": No address associated with hostname 
08-31 03:46:22.204: W/System.err(13238): at java.net.InetAddress.lookupHostByName(InetAddress.java:394) 
08-31 03:46:22.222: W/System.err(13238): at java.net.InetAddress.getAllByNameImpl(InetAddress.java:236) 
08-31 03:46:22.222: W/System.err(13238): at java.net.InetAddress.getAllByName(InetAddress.java:214) 

Answer 1

原來Android的Log.getStackTraceString其用於通過Log.X吞下的UnknownHostException。 :(

來源：http://grepcode.com/file/repository.grepcode.com/java/ext/com.google.android/android/4.2.2_r1/android/util/Log.java#Log.getStackTraceString%28java.lang.Throwable%29

public static String getStackTraceString(Throwable tr) { 
    if (tr == null) { 
     return ""; 
    } 

    // This is to reduce the amount of log spew that apps do in the non-error 
    // condition of the network being unavailable. 
    Throwable t = tr; 
    while (t != null) { 
     if (t instanceof UnknownHostException) { 
      return ""; 
     } 
     t = t.getCause(); 
    } 

    StringWriter sw = new StringWriter(); 
    PrintWriter pw = new PrintWriter(sw); 
    tr.printStackTrace(pw); 
    return sw.toString(); 
} 

這一切都非常好減少日誌噴涌但甚至沒有告訴我有什麼例外的是不好的JooJoo