3.2.1 类使用模式

使用上面的主类的方法，可以很容易地调用对象的各种操作。但是我们如何从这些类中获取事件/通知？以上每个主要类（Media除外）将在回调方法中获取他们的事件。所以要处理这些事件，只需从对应的类（Endpoint，Call，Account或Buddy）派生一个类，并实现/重载相关的方法（取决于想要处理的事件）。更多内容将在后面的章节中进行说明。

3.2.2错误处理

使用异常作为报告错误的手段，因为这将使程序更自然地流动。产生错误的操作会引起错误异常。如果希望以更结构化的方式显示错误，则Error类有几个成员来解释错误，例如引发错误的操作名称，错误代码和错误消息本身。

3.2.3 异步操作

如果您已经使用PJSIP开发应用程序，那么您已经了解了这些应用程序。在PJSIP中，涉及发送和接收SIP消息的所有操作都是异步的，这意味着调用该操作的功能将立即完成，您将在回调中获得完成状态。

例如Call类的makeCall( ) 方法。此功能用于启动到目的地的呼出。当此函数成功返回时，并不意味着该呼叫已经建立，而是意味着该呼叫已成功启动。您将在Call类的onCallState（）回调方法中获取呼叫进度和/或完成的报告。

3.2.4 线程

对于需要轮询的平台，PJSUA2模块提供自己的工作线程来轮询PJSIP，因此无需实例化您的轮询线程。如前所述，应用程序应该准备好让主线程调用不同线程的回调。PJSUA2模块本身是线程安全的。

通常，尤其是如果使用高级语言（如Python）调用PJSUA2，则需要通过将EpConfig.uaConfig.threadCnt 设置为0，来禁用PJSUA2内部工作线程。因为高级环境不喜欢被外部线程调用（如PJSIP的工作线程）。

class MyApp {

    private MyLogWriter logWriter;

    public void init()

    {

        /* Maintain reference to log writer to avoid premature cleanup by GC */

        logWriter = new MyLogWriter();

        epConfig.getLogConfig.setWriter(logWriter);

    }

}

acc.delete();

EpConfig epCfg;

JsonDocument jDoc;

epCfg.uaConfig.maxCalls = 61;

epCfg.uaConfig.userAgent = "Just JSON Test";

jDoc.writeObject(epCfg);

jDoc.saveFile("jsontest.js");

$ python

> import pjsua2

> ^Z

#include <pjsua2.hpp>

#include <iostream>

using namespace pj;

// Subclass to extend the Account and get notifications etc.

class MyAccount : public Account 
{

public:

    virtual void onRegState(OnRegStateParam &prm) 
　　{

        AccountInfo ai = getInfo();

        std::cout << (ai.regIsActive? "*** Register:" : "*** Unregister:")

                  << " code=" << prm.code << std::endl;

    }

};

int main()

{

    Endpoint ep;

    ep.libCreate();

    // Initialize endpoint

    EpConfig ep_cfg;

    ep.libInit( ep_cfg );

    // Create SIP transport. Error handling sample is shown

    TransportConfig tcfg;

    tcfg.port = ;

    try 
　　{

        ep.transportCreate(PJSIP_TRANSPORT_UDP, tcfg);

    } 
　　 catch (Error &err) 
　　 {

        std::cout << err.info() << std::endl;

        return ;

    }

    // Start the library (worker threads etc)

    ep.libStart();

    std::cout << "*** PJSUA2 STARTED ***" << std::endl;

    // Configure an AccountConfig

    AccountConfig acfg;

    acfg.idUri = "sip:test@pjsip.org";

    acfg.regConfig.registrarUri = "sip:pjsip.org";

    AuthCredInfo cred("digest", "*", "test", , "secret");

    acfg.sipConfig.authCreds.push_back( cred );

    // Create the account

    MyAccount *acc = new MyAccount;

    acc->create(acfg);

    // Here we don't have anything else to do..

    pj_thread_sleep();

    // Delete the account. This will unregister from server

    delete acc;

    // This will implicitly shutdown the library

    return ;

}

# Subclass to extend the Account and get notifications etc.

class Account(pj.Account):

  def onRegState(self, prm):

      print "***OnRegState: " + prm.reason

# pjsua2 test function

def pjsua2_test():

  # Create and initialize the library

  ep_cfg = pj.EpConfig()

  ep = pj.Endpoint()

  ep.libCreate()

  ep.libInit(ep_cfg)

  # Create SIP transport. Error handling sample is shown

  sipTpConfig = pj.TransportConfig();

  sipTpConfig.port = 5060;

  ep.transportCreate(pj.PJSIP_TRANSPORT_UDP, sipTpConfig);

  # Start the library

  ep.libStart();

  acfg = pj.AccountConfig();

  acfg.idUri = "sip:test@pjsip.org";

  acfg.regConfig.registrarUri = "sip:pjsip.org";

  cred = pj.AuthCredInfo("digest", "*", "test", 0, "pwtest");

  acfg.sipConfig.authCreds.append( cred );

  # Create the account

  acc = Account();

  acc.create(acfg);

  # Here we don't have anything else to do..

  time.sleep(10);

  # Destroy the library

  ep.libDestroy()

#

# main()

#

if __name__ == "__main__":

  pjsua2_test()

import org.pjsip.pjsua2.*;

// Subclass to extend the Account and get notifications etc.

class MyAccount extends Account {

  @Override

  public void onRegState(OnRegStateParam prm) {

      System.out.println("*** On registration state: " + prm.getCode() + prm.getReason());

  }

}

public class test {

  static {

      System.loadLibrary("pjsua2");

      System.out.println("Library loaded");

  }

  public static void main(String argv[]) {

      try {

          // Create endpoint

          Endpoint ep = new Endpoint();

          ep.libCreate();

          // Initialize endpoint

          EpConfig epConfig = new EpConfig();

          ep.libInit( epConfig );

          // Create SIP transport. Error handling sample is shown

          TransportConfig sipTpConfig = new TransportConfig();

          sipTpConfig.setPort(5060);

          ep.transportCreate(pjsip_transport_type_e.PJSIP_TRANSPORT_UDP, sipTpConfig);

          // Start the library

          ep.libStart();

          AccountConfig acfg = new AccountConfig();

          acfg.setIdUri("sip:test@pjsip.org");

          acfg.getRegConfig().setRegistrarUri("sip:pjsip.org");

          AuthCredInfo cred = new AuthCredInfo("digest", "*", "test", 0, "secret");

          acfg.getSipConfig().getAuthCreds().add( cred );

          // Create the account

          MyAccount acc = new MyAccount();

          acc.create(acfg);

          // Here we don't have anything else to do..

          Thread.sleep(10000);

          /* Explicitly delete the account.

           * This is to avoid GC to delete the endpoint first before deleting

           * the account.

           */

          acc.delete();

          // Explicitly destroy and delete endpoint

          ep.libDestroy();

          ep.delete();

      } catch (Exception e) {

          System.out.println(e);

          return;

      }

  }

}