当我想从服务器（java）向Firebase发送通知而不是向设备发送通知时，有人可以向我解释推送通知的完整过程吗？
在我的下面示例中，结果是Android Notification Response：
{
"multicast_id":7880177496704383133,
"success":0,
"failure":1,
"canonical_ids":0,
"results":[{"error":"InvalidRegistration"}]
}
这是由于错误＆＃34; TO＆＃34;价值来自何处？
我已经创建了一个虚拟Firebase项目包含 包com.push.notification;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import net.sf.json.JSONException;
import net.sf.json.JSONObject;
public class FCM {
final static private String FCM_URL = "https://fcm.googleapis.com/fcm/send";
/**
*
* Method to send push notification to Android FireBased Cloud messaging
Server.
*
* @param tokenId Generated and provided from Android Client Developer
* @param server_key Key which is Generated in FCM Server
* @param message which contains actual information.
*
*/
static void send_FCM_Notification(String tokenId, String server_key, String
message){
try{
// Create URL instance.
URL url = new URL(FCM_URL);
// create connection.
HttpURLConnection conn;
conn = (HttpURLConnection) url.openConnection();
conn.setUseCaches(false);
conn.setDoInput(true);
conn.setDoOutput(true);
//set method as POST or GET
conn.setRequestMethod("POST");
//pass FCM server key
conn.setRequestProperty("Authorization","key="+server_key);
//Specify Message Format
conn.setRequestProperty("Content-Type","application/json");
//Create JSON Object & pass value
JSONObject infoJson = new JSONObject();
infoJson.put("title","Here is your notification.");
infoJson.put("body", message);
JSONObject json = new JSONObject();
json.put("to",tokenId.trim());
json.put("notification", infoJson);
OutputStreamWriter wr = new
OutputStreamWriter(conn.getOutputStream());
wr.write(json.toString());
wr.flush();
int status = 0;
if( null != conn ){
status = conn.getResponseCode();
}
if( status != 0){
if( status == 200 ){
//SUCCESS message
BufferedReader reader = new BufferedReader(new
InputStreamReader(conn.getInputStream()));
System.out.println("Android Notification Response : " +
reader.readLine());
}else if(status == 401){
//client side error
System.out.println("Notification Response : TokenId : " +
tokenId + " Error occurred :");
}else if(status == 501){
//server side error
System.out.println("Notification Response : [
errorCode=ServerError ] TokenId : " + tokenId);
}else if( status == 503){
//server side error
System.out.println("Notification Response : FCM Service is
Unavailable TokenId : " + tokenId);
}
}
}catch(MalformedURLException mlfexception){
// Prototcal Error
System.out.println("Error occurred while sending push
Notification!.." + mlfexception.getMessage());
}catch(IOException mlfexception){
//URL problem
System.out.println("Reading URL, Error occurred while sending push
Notification!.." + mlfexception.getMessage());
}catch(JSONException jsonexception){
//Message format error
System.out.println("Message Format, Error occurred while sending
push Notification!.." + jsonexception.getMessage());
}catch (Exception exception) {
//General Error or exception.
System.out.println("Error occurred while sending push
Notification!.." + exception.getMessage());
}
}
}