海康威视 sdk 报警订阅 java代码编写

海康威视提供了基于Java的SDK，可以通过该SDK实现报警订阅。以下是基本的Java代码示例：

import com.sun.jna.NativeLong;
import com.sun.jna.Pointer;
import com.sun.jna.ptr.NativeLongByReference;
import com.sun.jna.ptr.PointerByReference;
import com.sun.jna.win32.StdCallLibrary;

// 定义回调函数的接口
public interface FMSGCallBack_V31 extends StdCallLibrary.StdCallCallback {
    public void invoke(NativeLong lCommand, NET_DVR_ALARMER pAlarmer, Pointer pAlarmInfo, NativeLong dwBufLen, Pointer pUser);
}

public class AlarmSubscribe {
    // 加载SDK库文件
    static {
        System.loadLibrary("HCNetSDK");
    }

    // 登录设备
    public static NativeLong login(String ip, short port, String username, String password) {
        HCNetSDK.NET_DVR_USER_LOGIN_INFO loginInfo = new HCNetSDK.NET_DVR_USER_LOGIN_INFO();
        loginInfo.sDeviceAddress = new byte[HCNetSDK.NET_DVR_DEV_ADDRESS_MAX_LEN];
        System.arraycopy(ip.getBytes(), 0, loginInfo.sDeviceAddress, 0, ip.length());
        loginInfo.wPort = port;
        loginInfo.sUserName = new byte[HCNetSDK.NET_DVR_LOGIN_USERNAME_MAX_LEN];
        System.arraycopy(username.getBytes(), 0, loginInfo.sUserName, 0, username.length());
        loginInfo.sPassword = new byte[HCNetSDK.NET_DVR_LOGIN_PASSWD_MAX_LEN];
        System.arraycopy(password.getBytes(), 0, loginInfo.sPassword, 0, password.length());

        HCNetSDK.NET_DVR_DEVICEINFO_V40 deviceInfo = new HCNetSDK.NET_DVR_DEVICEINFO_V40();
        return HCNetSDK.INSTANCE.NET_DVR_Login_V40(loginInfo, deviceInfo);
    }

    // 注册回调函数
    public static NativeLong registerAlarmCallback(NativeLong lUserID) {
        FMSGCallBack_V31 callBack = new FMSGCallBack_V31() {
            @Override
            public void invoke(NativeLong lCommand, NET_DVR_ALARMER pAlarmer, Pointer pAlarmInfo, NativeLong dwBufLen, Pointer pUser) {
                System.out.println("Alarm Info Received");
            }
        };

        PointerByReference pUser = new PointerByReference();
        return HCNetSDK.INSTANCE.NET_DVR_SetDVRMessageCallBack_V31(callBack, pUser);
    }

    // 设置报警布防
    public static boolean setupAlarmChan(NativeLong lUserID) {
        HCNetSDK.NET_DVR_SETUPALARM_PARAM alarmParam = new HCNetSDK.NET_DVR_SETUPALARM_PARAM();
        alarmParam.dwSize = alarmParam.size();
        return HCNetSDK.INSTANCE.NET_DVR_SetupAlarmChan_V41(lUserID, alarmParam) != null;
    }

    // 关闭报警布防
    public static boolean closeAlarmChan(NativeLong lAlarmHandle) {
        return HCNetSDK.INSTANCE.NET_DVR_CloseAlarmChan_V30(lAlarmHandle);
    }

    // 注销登录
    public static boolean logout(NativeLong lUserID) {
        return HCNetSDK.INSTANCE.NET_DVR_Logout(lUserID);
    }

    public static void main(String[] args) {
        // 登录设备
        NativeLong lUserID = login("192.168.0.1", (short) 8000, "admin", "12345");

        if (lUserID.intValue() < 0) {
            System.out.println("Login failed");
            return;
        }

        // 注册回调函数
        NativeLong lAlarmHandle = registerAlarmCallback(lUserID);

        if (lAlarmHandle.intValue() < 0) {
            System.out.println("Register callback failed");
            return;
        }

        // 设置报警布防
        if (!setupAlarmChan(lUserID)) {
            System.out.println("Setup alarm failed");
            closeAlarmChan(lAlarmHandle);
            return;
        }

        // 等待报警信息
        System.out.println("Waiting for alarm info...");

        try {
            Thread.sleep(30000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }

        // 关闭报警布防
        if (!closeAlarmChan(lAlarmHandle)) {
            System.out.println("Close alarm failed");
        }

        // 注销登录
        if (!logout(lUserID)) {
            System.out.println("Logout failed");
        }
    }
}

该示例代码中定义了登录设备、注册回调函数、设置报警布防、关闭报警布防、注销登录等操作的具体实现。需要注意的是，回调函数需要在`FMSGCallBack_V31`接口的`invoke`方法中实现具体的回调逻辑。在本示例中，回调函数只简单地输出一行日志信息。实际应用中，需要根据具体的业务需求实现回调函数的逻辑。