所以我认为我在以前的主题中质疑错误的方式。我最好这样说。 我正在尝试解析XML数据:
<playlist>
<title>![CDATA[New Playlist]]</title>
<items>
<item>
<title>HAMD(LA ILAHA ILLALLAH)</title>
<description>Recited By :Alhaaj Muhammad Owais Raza Qadri -- Written By: Mufti-e-Azam Hind Molana Mustafa Raza Khan Noori</description>
<image>http://xxx.xxx.xxx.xxx/~kanz/video/Images/9.jpg</image>
<startFromThis>true</startFromThis>
<duration>510</duration>
<source>http://xxx.xxx.xxx.xxx/~kanz/video/flv/9.flv</source>
<sourceAlt>http://xxx.xxx.xxx.xxx/~kanz/video/mp4/9.mp4</sourceAlt>
<sourceType>direct</sourceType>
</item>
</items>
</playlist>
在我的Activity中,我做的是这个,但是logcat给出了空指针异常。这是我的Activity,下面是logcat错误。
static final String URL = "http://xxx.xxx.xxx.xxx/~kanz/video/XML/9.xml";
// XML node keyse.
static final String KEY_SONG = "item"; // parent node
static final String KEY_TITLE = "title";
static final String KEY_ARTIST = "description";
static final String KEY_THUMB_URL = "image";
static final String KEY_DURATION = "duration";
NodeList nl = doc.getElementsByTagName(KEY_SONG);
// looping through all song nodes <song>
for (int i = 0; i < nl.getLength(); i++) {
// creating new HashMap
HashMap<String, String> map = new HashMap <String, String>();
Element e = (Element) nl.item(i);
// adding each child node to HashMap key => value
map.put(KEY_TITLE, parser.getValue(e, KEY_TITLE));
map.put(KEY_ARTIST, parser.getValue(e, KEY_ARTIST));
map.put(KEY_THUMB_URL, parser.getValue(e, KEY_THUMB_URL));
map.put(KEY_DURATION, parser.getValue(e, KEY_DURATION));
// adding HashList to ArrayList
songsList.add(map);
}
Logcat给出意外令牌错误并返回null,这会导致空指针异常。
03-28 14:31:34.059: E/Error:(895): Unexpected token (position:TEXT @1:4 in java.io.StringReader@40d220e0)
03-28 14:31:34.080: I/System.out(895): null
03-28 14:42:59.560: D/AndroidRuntime(978): Shutting down VM
03-28 14:42:59.560: W/dalvikvm(978): threadid=1: thread exiting with uncaught exception (group=0x40a71930)
03-28 14:42:59.639: E/AndroidRuntime(978): FATAL EXCEPTION: main
03-28 14:42:59.639: E/AndroidRuntime(978): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.razatubevidurl/com.example.razatubevidurl.CustomizedListView}: java.lang.NullPointerException
03-28 14:42:59.639: E/AndroidRuntime(978): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2180)
03-28 14:42:59.639: E/AndroidRuntime(978): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
03-28 14:42:59.639: E/AndroidRuntime(978): at android.app.ActivityThread.access$600(ActivityThread.java:141)
03-28 14:42:59.639: E/AndroidRuntime(978): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234)
03-28 14:42:59.639: E/AndroidRuntime(978): at android.os.Handler.dispatchMessage(Handler.java:99)
03-28 14:42:59.639: E/AndroidRuntime(978): at android.os.Looper.loop(Looper.java:137)
03-28 14:42:59.639: E/AndroidRuntime(978): at android.app.ActivityThread.main(ActivityThread.java:5041)
03-28 14:42:59.639: E/AndroidRuntime(978): at java.lang.reflect.Method.invokeNative(Native Method)
03-28 14:42:59.639: E/AndroidRuntime(978): at java.lang.reflect.Method.invoke(Method.java:511)
03-28 14:42:59.639: E/AndroidRuntime(978): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
03-28 14:42:59.639: E/AndroidRuntime(978): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
03-28 14:42:59.639: E/AndroidRuntime(978): at dalvik.system.NativeStart.main(Native Method)
03-28 14:42:59.639: E/AndroidRuntime(978): Caused by: java.lang.NullPointerException
请告诉我我做错了什么。我认为我之前的问题含糊不清,在这一个问题上,我尽力使问题清晰易懂。
答案 0 :(得分:0)
我猜这是关于编码的。也许你的解析器不喜欢感叹号(!)。您能确保使用具有正确编码的XML文件吗? (UTF-8)
否则,您遇到此问题:KXmlParser throws "Unexpected token" exception at the start of RSS pasing。
我用Google搜索,看起来最简单的修复是here。 您可以尝试添加此方法。 (从您使用的教程中,将其放在ImageLoader类中。)
import java.io.PushbackInputStream;
private InputStream checkForUtf8BOMAndDiscardIfAny(InputStream inputStream) throws IOException {
PushbackInputStream pushbackInputStream = new PushbackInputStream(new BufferedInputStream(inputStream), 3);
byte[] bom = new byte[3];
if (pushbackInputStream.read(bom) != -1) {
if (!(bom[0] == (byte) 0xEF && bom[1] == (byte) 0xBB && bom[2] == (byte) 0xBF)) {
pushbackInputStream.unread(bom);
}
}
return pushbackInputStream; }
然后你可以做
InputStream is=conn.getInputStream();
is = checkForUtf8BOMAndDiscardIfAny(is);
我没有机会测试该方法,但它应该这样做。 另外,请参阅Byte order mark screws up file reading in Java。