android 4.0.3自己写软件无法访问网络

URL url = new URL("http://192.168.1.104:8080/testone/1.png");
System.out.println(url);
HttpURLConnection urlconnection = (HttpURLConnection)url.openConnection();
urlconnection.setConnectTimeout(5000);
urlconnection.setRequestMethod("GET");
urlconnection.connect();
ByteArrayOutputStream out = null;
if(urlconnection.getResponseCode() == 200){
InputStream input = urlconnection.getInputStream();
 out = new ByteArrayOutputStream();
byte[] buff = new byte[1024];
int len = 0;
while((len = input.read(buff))!=-1){
out.write(buff,0,len);
}
input.close();
}1.url经手机浏览器测试可以用，
05-28 02:39:46.652: E/AndroidRuntime(2745): FATAL EXCEPTION: main
05-28 02:39:46.652: E/AndroidRuntime(2745): android.os.NetworkOnMainThreadException
05-28 02:39:46.652: E/AndroidRuntime(2745):  at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1099)
05-28 02:39:46.652: E/AndroidRuntime(2745):  at libcore.io.BlockGuardOs.connect(BlockGuardOs.java:84)
05-28 02:39:46.652: E/AndroidRuntime(2745):  at libcore.io.IoBridge.connectErrno(IoBridge.java:138)
05-28 02:39:46.652: E/AndroidRuntime(2745):  at libcore.io.IoBridge.connect(IoBridge.java:112)
05-28 02:39:46.652: E/AndroidRuntime(2745):  at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:192)
05-28 02:39:46.652: E/AndroidRuntime(2745):  at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:459)
05-28 02:39:46.652: E/AndroidRuntime(2745):  at java.net.Socket.connect(Socket.java:842)
05-28 02:39:46.652: E/AndroidRuntime(2745):  at libcore.net.http.HttpConnection.<init>(HttpConnection.java:77)
05-28 02:39:46.652: E/AndroidRuntime(2745):  at libcore.net.http.HttpConnection.<init>(HttpConnection.java:50)
05-28 02:39:46.652: E/AndroidRuntime(2745):  at libcore.net.http.HttpConnection$Address.connect(HttpConnection.java:351)
05-28 02:39:46.652: E/AndroidRuntime(2745):  at libcore.net.http.HttpConnectionPool.get(HttpConnectionPool.java:86)
05-28 02:39:46.652: E/AndroidRuntime(2745):  at libcore.net.http.HttpConnection.connect(HttpConnection.java:128)
05-28 02:39:46.652: E/AndroidRuntime(2745):  at libcore.net.http.HttpEngine.openSocketConnection(HttpEngine.java:308)
05-28 02:39:46.652: E/AndroidRuntime(2745):  at libcore.net.http.HttpEngine.connect(HttpEngine.java:303)
05-28 02:39:46.652: E/AndroidRuntime(2745):  at libcore.net.http.HttpEngine.sendSocketRequest(HttpEngine.java:282)
05-28 02:39:46.652: E/AndroidRuntime(2745):  at libcore.net.http.HttpEngine.sendRequest(HttpEngine.java:232)
05-28 02:39:46.652: E/AndroidRuntime(2745):  at libcore.net.http.HttpURLConnectionImpl.connect(HttpURLConnectionImpl.java:80)
05-28 02:39:46.652: E/AndroidRuntime(2745):  at com.example.sqllite.ImageConnection.image(ImageConnection.java:28)
05-28 02:39:46.652: E/AndroidRuntime(2745):  at com.example.sqllite.MainActivity$1.onClick(MainActivity.java:65)
05-28 02:39:46.652: E/AndroidRuntime(2745):  at android.view.View.performClick(View.java:3511)
05-28 02:39:46.652: E/AndroidRuntime(2745):  at android.view.View$PerformClick.run(View.java:14105)
05-28 02:39:46.652: E/AndroidRuntime(2745):  at android.os.Handler.handleCallback(Handler.java:605)
05-28 02:39:46.652: E/AndroidRuntime(2745):  at android.os.Handler.dispatchMessage(Handler.java:92)
05-28 02:39:46.652: E/AndroidRuntime(2745):  at android.os.Looper.loop(Looper.java:137)
05-28 02:39:46.652: E/AndroidRuntime(2745):  at android.app.ActivityThread.main(ActivityThread.java:4424)
05-28 02:39:46.652: E/AndroidRuntime(2745):  at java.lang.reflect.Method.invokeNative(Native Method)
05-28 02:39:46.652: E/AndroidRuntime(2745):  at java.lang.reflect.Method.invoke(Method.java:511)
05-28 02:39:46.652: E/AndroidRuntime(2745):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
05-28 02:39:46.652: E/AndroidRuntime(2745):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
05-28 02:39:46.652: E/AndroidRuntime(2745):  at dalvik.system.NativeStart.main(Native Method)
Android 4.0URL