安卓应用doPost

Question

我在从我的android应用程序到我的Google应用程序执行简单的http post请求时遇到了问题。

因此，下面是错误消息：

07-16 15:58:02.314: E/AndroidRuntime(911): FATAL EXCEPTION: main
07-16 15:58:02.314: E/AndroidRuntime(911): java.lang.IllegalStateException: Could not     execute method of the activity

它发生在我的安卓应用程序中的httpclient.execute命令中：

ConnectivityManager connMgr = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo networkInfo = connMgr.getActiveNetworkInfo();
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("http://localhost:8888/mywebapp");
try {
// Execute HTTP Post Request
HttpResponse response = httpclient.execute(httppost);
}

在我的服务器上，我的post方法中没有我到达的踪迹：

protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws  ServletException, IOException {
System.out.println("SYL: POST request received");
super.doPost(req, resp);
}

服务器是在本地eclipse下运行的google webb应用程序，配置如下：

<servlet-name>MyWebApp</servlet-name>
<servlet-class>com.my.mywebapp.MyWebAppServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>MyWebApp</servlet-name>
<url-pattern>/mywebapp/*</url-pattern>
</servlet-mapping>

如果测试了我通过web导航器调用的get方法，它就能正常工作。但是在java中调用get (和我对post所做的一样)是不起作用的。就像在android应用程序中一样，无法与我的服务器建立连接。

我把这些权限放在：

<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />

有人能帮帮我吗？？

谢谢。

PS：

使用10.0.2.2替换localhost时仍然会出现相同的错误。我正在复制完整的跟踪：

07-16 18:13:34.945: E/AndroidRuntime(1081): FATAL EXCEPTION: main
07-16 18:13:34.945: E/AndroidRuntime(1081): java.lang.IllegalStateException: Could not execute method of the activity
07-16 18:13:34.945: E/AndroidRuntime(1081):     at android.view.View$1.onClick(View.java:3044)
07-16 18:13:34.945: E/AndroidRuntime(1081):     at android.view.View.performClick(View.java:3511)
07-16 18:13:34.945: E/AndroidRuntime(1081):     at android.view.View$PerformClick.run(View.java:14105)
07-16 18:13:34.945: E/AndroidRuntime(1081):     at android.os.Handler.handleCallback(Handler.java:605)
07-16 18:13:34.945: E/AndroidRuntime(1081):     at android.os.Handler.dispatchMessage(Handler.java:92)
07-16 18:13:34.945: E/AndroidRuntime(1081):     at android.os.Looper.loop(Looper.java:137)
07-16 18:13:34.945: E/AndroidRuntime(1081):     at android.app.ActivityThread.main(ActivityThread.java:4424)
07-16 18:13:34.945: E/AndroidRuntime(1081):     at java.lang.reflect.Method.invokeNative(Native Method)
07-16 18:13:34.945: E/AndroidRuntime(1081):     at java.lang.reflect.Method.invoke(Method.java:511)
07-16 18:13:34.945: E/AndroidRuntime(1081):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
07-16 18:13:34.945: E/AndroidRuntime(1081):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
07-16 18:13:34.945: E/AndroidRuntime(1081):     at dalvik.system.NativeStart.main(Native Method)
07-16 18:13:34.945: E/AndroidRuntime(1081): Caused by: java.lang.reflect.InvocationTargetException
07-16 18:13:34.945: E/AndroidRuntime(1081):     at java.lang.reflect.Method.invokeNative(Native Method)
07-16 18:13:34.945: E/AndroidRuntime(1081):     at java.lang.reflect.Method.invoke(Method.java:511)
07-16 18:13:34.945: E/AndroidRuntime(1081):     at android.view.View$1.onClick(View.java:3039)
07-16 18:13:34.945: E/AndroidRuntime(1081):     ... 11 more
07-16 18:13:34.945: E/AndroidRuntime(1081): Caused by: android.os.NetworkOnMainThreadException
07-16 18:13:34.945: E/AndroidRuntime(1081):     at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1099)
07-16 18:13:34.945: E/AndroidRuntime(1081):     at java.net.InetAddress.lookupHostByName(InetAddress.java:391)
07-16 18:13:34.945: E/AndroidRuntime(1081):     at java.net.InetAddress.getAllByNameImpl(InetAddress.java:242)
07-16 18:13:34.945: E/AndroidRuntime(1081):     at java.net.InetAddress.getAllByName(InetAddress.java:220)
07-16 18:13:34.945: E/AndroidRuntime(1081):     at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:137)
07-16 18:13:34.945: E/AndroidRuntime(1081):     at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164)
07-16 18:13:34.945: E/AndroidRuntime(1081):     at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119)
07-16 18:13:34.945: E/AndroidRuntime(1081):     at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:360)
07-16 18:13:34.945: E/AndroidRuntime(1081):     at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555)
07-16 18:13:34.945: E/AndroidRuntime(1081):     at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487)
07-16 18:13:34.945: E/AndroidRuntime(1081):     at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:465)
07-16 18:13:34.945: E/AndroidRuntime(1081):     at com.my.my.MyActivity.sendMessage(MyActivity.java:72)
07-16 18:13:34.945: E/AndroidRuntime(1081):     ... 14 more

Answer 1

如果您在本地服务器上调试，请更改您要访问的IP，并设置此IP: 10.0.2.2。所以，你的httpost看起来是这样的：

HttpPost httppost = new HttpPost("http://10.0.2.2:8888/mywebapp");

有关更多信息，请访问http://developer.android.com/tools/devices/emulator.html#networkaddresses