推送，極光推送

推送的原理其實也很簡單，拿極光推送來說，首先，APP登錄的時候，調用極光的API，設置當前登錄的信息到極光；服務器發送推送時，只要將需要推送的信息和相應的唯一標識傳給極光，就可以了。

附上服務器端簡單代碼：

public static void testSendPush(String appKey ,String masterSecret,
			String jsonString,String alias) {
		try {
			MSG_CONTENT = jsonString;

			jpushClient = new JPushClient(masterSecret, appKey, 3);
			PushPayload payload = buildPushObject_android_and_ios(jsonString, alias);
			PushResult result = jpushClient.sendPush(payload);

			LOG.info("Got result - " + result);

		} catch (APIConnectionException e) {
			LOG.error("Connection error. Should retry later. ", e);

		} catch (APIRequestException e) {
			LOG.error("Error response from JPush server. Should review and fix it. ", e);
			LOG.info("HTTP Status: " + e.getStatus());
			LOG.info("Error Code: " + e.getErrorCode());
			LOG.info("Error Message: " + e.getErrorMessage());
			LOG.info("Msg ID: " + e.getMsgId());
		}
	}

public static PushPayload buildPushObject_android_and_ios(String jsonString,String alias) {
       return PushPayload.newBuilder()
               .setPlatform(Platform.android_ios())
               .setAudience(Audience.newBuilder()
            		   .addAudienceTarget(AudienceTarget.alias(alias))
            		   .build())
                .setMessage(Message.newBuilder()
                       .setMsgContent(jsonString)
                       .addExtra("from", "JPush")
                       .build())
               .build();
   }