4.3 可以设置哪些Java命令行选项以允许对JVM进行远程调试？（二合一）｜ Java Debug 笔记

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提问：可以设置哪些Java命令行选项以允许对JVM进行远程调试？

我知道有一些JAVA_OPTS设置可以远程调试Java程序。

这些命令是什么，它们是什么意思？

以下代码对于Java 5及更低版本进行设置。

-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=n,address=1044

对于Java 5及更高版本，请使用以下命令运行它：

-agentlib:jdwp=transport=dt_socket,server=y,suspend=n,address=1044

输出

java -Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=n,address=1044 HelloWhirled
Listening for transport dt_socket at address: 1044
Hello whirled

提问：如何在Java中为Android设置HttpResponse超时

我创建了以下函数来检查连接状态：

private void checkConnectionStatus() {
    HttpClient httpClient = new DefaultHttpClient();

    try {
      String url = "http://xxx.xxx.xxx.xxx:8000/GaitLink/"
                   + strSessionString + "/ConnectionStatus";
      Log.d("phobos", "performing get " + url);
      HttpGet method = new HttpGet(new URI(url));
      HttpResponse response = httpClient.execute(method);

      if (response != null) {
        String result = getResponse(response.getEntity());
        ...

当我关闭服务器以测试执行情况时，在下面这等待了很长时间

HttpResponse response = httpClient.execute(method);

有谁知道如何设置超时以避免等待太久？

谢谢！

回答1:

在我的示例代码中，设置了两个超时。连接超时抛出java.net.SocketTimeoutException: Socket is not connected，套接字超时java.net.SocketTimeoutException: The operation timed out。

HttpGet httpGet = new HttpGet(url);
HttpParams httpParameters = new BasicHttpParams();
// Set the timeout in milliseconds until a connection is established.
// The default value is zero, that means the timeout is not used. 
int timeoutConnection = 3000;
HttpConnectionParams.setConnectionTimeout(httpParameters, timeoutConnection);
// Set the default socket timeout (SO_TIMEOUT) 
// in milliseconds which is the timeout for waiting for data.
int timeoutSocket = 5000;
HttpConnectionParams.setSoTimeout(httpParameters, timeoutSocket);

DefaultHttpClient httpClient = new DefaultHttpClient(httpParameters);
HttpResponse response = httpClient.execute(httpGet);

如果要设置HTTPClient的参数（例如DefaultHttpClient或AndroidHttpClient）

httpClient.setParams(httpParameters);