【发布时间】：2014-03-19 16:49:36
【问题描述】：
您好，我尝试从网站读取 xml 文件，但我遇到了问题。
当我按下按钮时，我创建了“DOMCreate”类的对象，下一个应用程序崩溃了。
下面我放了 logcat 的错误：
03-19 17:34:10.027 17003-17003/com.example.currencyconverter.app E/Trace﹕ error opening trace file: No such file or directory (2)
03-19 17:34:10.037 17003-17003/com.example.currencyconverter.app W/ActivityThread﹕ Application com.example.currencyconverter.app can be debugged on port 8100...
03-19 17:34:10.347 17003-17003/com.example.currencyconverter.app I/Adreno200-EGL﹕ <qeglDrvAPI_eglInitialize:299>: EGL 1.4 QUALCOMM build: AU_LINUX_ANDROID_JB_REL_2.0.3.04.01.02.21.081_msm7627a_JB_REL_2.0.3_CL2820657_release_AU (CL2820657)
Build Date: 01/22/13 Tue
Local Branch:
Remote Branch: quic/jb_rel_2.0.3
Local Patches: NONE
Reconstruct Branch: AU_LINUX_ANDROID_JB_REL_2.0.3.04.01.02.21.081 + NOTHING
03-19 17:34:10.397 17003-17003/com.example.currencyconverter.app E/copybit﹕ Error opening frame buffer errno=13 (Permission denied)
03-19 17:34:10.397 17003-17003/com.example.currencyconverter.app W/Adreno200-EGLSUB﹕ <updater_create_surface_state:342>: updater_create_surface_state failed to open copybit, error: -13
03-19 17:34:10.397 17003-17003/com.example.currencyconverter.app D/memalloc﹕ ion: Mapped buffer base:0x53bee000 size:1536000 offset:0 fd:61
03-19 17:34:10.397 17003-17003/com.example.currencyconverter.app D/memalloc﹕ ion: Mapped buffer base:0x40045000 size:4096 offset:0 fd:63
03-19 17:34:10.557 17003-17003/com.example.currencyconverter.app D/memalloc﹕ ion: Mapped buffer base:0x546a3000 size:1536000 offset:0 fd:66
03-19 17:34:10.557 17003-17003/com.example.currencyconverter.app D/memalloc﹕ ion: Mapped buffer base:0x40072000 size:4096 offset:0 fd:68
03-19 17:34:10.957 17003-17003/com.example.currencyconverter.app D/memalloc﹕ ion: Mapped buffer base:0x5491a000 size:1536000 offset:0 fd:70
03-19 17:34:10.957 17003-17003/com.example.currencyconverter.app D/memalloc﹕ ion: Mapped buffer base:0x4008b000 size:4096 offset:0 fd:72
03-19 17:34:11.457 17003-17003/com.example.currencyconverter.app D/memalloc﹕ ion: Mapped buffer base:0x54a91000 size:1536000 offset:0 fd:74
03-19 17:34:11.457 17003-17003/com.example.currencyconverter.app D/memalloc﹕ ion: Mapped buffer base:0x40091000 size:4096 offset:0 fd:76
03-19 17:34:19.727 17003-17003/com.example.currencyconverter.app W/dalvikvm﹕ threadid=1: thread exiting with uncaught exception (group=0x41051540)
03-19 17:34:19.767 17003-17003/com.example.currencyconverter.app E/AndroidRuntime﹕ FATAL EXCEPTION: main
java.lang.IllegalStateException: Could not execute method of the activity
at android.view.View$1.onClick(View.java:3609)
at android.view.View.performClick(View.java:4102)
at android.view.View$PerformClick.run(View.java:17085)
at android.os.Handler.handleCallback(Handler.java:615)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Looper.java:155)
at android.app.ActivityThread.main(ActivityThread.java:5520)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1029)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:796)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.reflect.InvocationTargetException
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at android.view.View$1.onClick(View.java:3604)
at android.view.View.performClick(View.java:4102)
at android.view.View$PerformClick.run(View.java:17085)
at android.os.Handler.handleCallback(Handler.java:615)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Looper.java:155)
at android.app.ActivityThread.main(ActivityThread.java:5520)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1029)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:796)
at dalvik.system.NativeStart.main(Native Method)
Caused by: android.os.NetworkOnMainThreadException
at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1208)
at java.net.InetAddress.lookupHostByName(InetAddress.java:388)
at java.net.InetAddress.getAllByNameImpl(InetAddress.java:239)
at java.net.InetAddress.getAllByName(InetAddress.java:214)
at libcore.net.http.HttpConnection.<init>(HttpConnection.java:70)
at libcore.net.http.HttpConnection.<init>(HttpConnection.java:50)
at libcore.net.http.HttpConnection$Address.connect(HttpConnection.java:340)
at libcore.net.http.HttpConnectionPool.get(HttpConnectionPool.java:87)
at libcore.net.http.HttpConnection.connect(HttpConnection.java:128)
at libcore.net.http.HttpEngine.openSocketConnection(HttpEngine.java:315)
at libcore.net.http.HttpEngine.connect(HttpEngine.java:310)
at libcore.net.http.HttpEngine.sendSocketRequest(HttpEngine.java:289)
at libcore.net.http.HttpEngine.sendRequest(HttpEngine.java:239)
at libcore.net.http.HttpURLConnectionImpl.getResponse(HttpURLConnectionImpl.java:273)
at libcore.net.http.HttpURLConnectionImpl.getInputStream(HttpURLConnectionImpl.java:168)
at com.example.currencyconverter.app.DOMCreator.<init>(DOMCreator.java:34)
at com.example.currencyconverter.app.MainActivity.exchangeRate(MainActivity.java:69)
at com.example.currencyconverter.app.MainActivity.convert(MainActivity.java:58)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at android.view.View$1.onClick(View.java:3604)
at android.view.View.performClick(View.java:4102)
at android.view.View$PerformClick.run(View.java:17085)
at android.os.Handler.handleCallback(Handler.java:615)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Looper.java:155)
at android.app.ActivityThread.main(ActivityThread.java:5520)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1029)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:796)
at dalvik.system.NativeStart.main(Native Method)
还有我的代码：
public class DOMCreator {
Document doc;
public DOMCreator(){
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder;
try{
URL nbp = new URL("http://www.nbp.pl/kursy/xml/a054z140319.xml");
URLConnection urlConn = nbp.openConnection();
builder = factory.newDocumentBuilder();
InputStream is = urlConn.getInputStream();
doc = builder.parse(is);
}catch(MalformedURLException e){
e.printStackTrace();
}catch(IOException e){
e.printStackTrace();
}catch(ParserConfigurationException e){
e.printStackTrace();
}catch(SAXException e){
e.printStackTrace();
}
}
public Double getRate(String scn){
if (doc!=null){
NodeList nodeList = doc.getElementsByTagName("pozycja");
for(int i = 0;i<nodeList.getLength();i++){
Element pos = (Element) nodeList.item(i);
NodeList childNodes = pos.getElementsByTagName("*");
String vName = "";
String vValue = "";
for(int j = 0; j<childNodes.getLength();j++){
Element posChild = (Element) nodeList.item(j);
if(posChild.getNodeName().equals("kod_waluty")){
vName = posChild.getTextContent();
}else if(posChild.getNodeName().equals("kurs_sredni")){
vValue = posChild.getTextContent();
}
}
if(vName.equals(scn)){
return Double.parseDouble(vValue);
}
}
}
return -1.0;
}
}
我不知道这段代码有什么问题。
【问题讨论】：
标签： java android xml-parsing domparser