Restlet一遍又一遍地重新启动内部http客户端答案

【问题标题】：Restlet restarting internal http client over and over againRestlet一遍又一遍地重新启动内部http客户端
【发布时间】：2012-06-01 01:44:48
【问题描述】：

我正在使用带有 org.restlet.ext.httpclient、org.restlet.ext.jackson 和 org.restlet.ext.json 的 Restlet 2.1 RC 4 从远程服务器获取数据。但是，对于 6 个对象，通过房屋内的无线数据连接需要 6 秒。

如您所见，除了 GC 之外，还有许多消息，例如 Starting the internal [HTTP/1.1] client 和 Stopping the internal[HTTP/1.1] client。这对应于需要花费大量时间的大型 GC。

06-01 03:21:46.913: RestletTrip(2653): Querying: [SOMEURL/SOMENUMBER]
06-01 03:21:46.933: I/org.restlet(2653): Starting the internal [HTTP/1.1] client
06-01 03:21:47.053: D/dalvikvm(2653): GC_CONCURRENT freed 708K, 34% free 9214K/13831K, external 576K/1020K, paused 3ms+3ms
06-01 03:21:47.053: I/org.restlet(2653): Stopping the internal[HTTP/1.1] client
06-01 03:21:47.103: D/dalvikvm(2653): GC_FOR_MALLOC freed 4924K, 61% free 5523K/13831K, external 576K/1020K, paused 31ms
06-01 03:21:47.173: D/dalvikvm(2653): GC_CONCURRENT freed 95K, 53% free 6574K/13831K, external 576K/1020K, paused 2ms+3ms
06-01 03:21:47.253: D/dalvikvm(2653): GC_CONCURRENT freed 46K, 43% free 8012K/13831K, external 576K/1020K, paused 2ms+3ms
06-01 03:21:47.734: I/global(2653): Loaded time zone names for en_US in 397ms.
06-01 03:21:48.014: RestletTrip(2653): Querying: [SOMEURL/SOMENUMBER]
06-01 03:21:48.124: D/dalvikvm(2653): GC_CONCURRENT freed 1225K, 38% free 8688K/13831K, external 576K/1020K, paused 3ms+3ms
06-01 03:21:48.124: I/org.restlet(2653): Stopping the internal[HTTP/1.1] client
06-01 03:21:48.134: I/org.restlet(2653): Starting the internal [HTTP/1.1] client
06-01 03:21:48.184: D/dalvikvm(2653): GC_FOR_MALLOC freed 5022K, 62% free 5341K/13831K, external 576K/1020K, paused 31ms
06-01 03:21:48.244: D/dalvikvm(2653): GC_CONCURRENT freed 96K, 55% free 6307K/13831K, external 576K/1020K, paused 2ms+3ms
06-01 03:21:48.314: D/dalvikvm(2653): GC_CONCURRENT freed 44K, 45% free 7663K/13831K, external 576K/1020K, paused 3ms+4ms
06-01 03:21:48.795: I/global(2653): Loaded time zone names for en_US in 405ms.
06-01 03:21:49.015: D/dalvikvm(2653): GC_CONCURRENT freed 695K, 37% free 8736K/13831K, external 576K/1020K, paused 3ms+3ms
06-01 03:21:49.155: RestletTrip(2653): Querying: [SOMEURL/SOMENUMBER]
06-01 03:21:49.165: I/org.restlet(2653): Starting the internal [HTTP/1.1] client
06-01 03:21:49.225: D/dalvikvm(2653): GC_FOR_MALLOC freed 672K, 30% free 9778K/13831K, external 576K/1020K, paused 34ms
06-01 03:21:49.225: I/org.restlet(2653): Stopping the internal[HTTP/1.1] client
06-01 03:21:49.265: D/dalvikvm(2653): GC_FOR_MALLOC freed 4902K, 61% free 5637K/14343K, external 576K/1020K, paused 32ms
06-01 03:21:49.325: D/dalvikvm(2653): GC_CONCURRENT freed 97K, 54% free 6703K/14343K, external 576K/1020K, paused 3ms+4ms
06-01 03:21:49.395: D/dalvikvm(2653): GC_CONCURRENT freed 54K, 44% free 8167K/14343K, external 576K/1020K, paused 3ms+3ms
06-01 03:21:49.876: I/global(2653): Loaded time zone names for en_US in 407ms.
06-01 03:21:50.136: RestletTrip(2653): Querying: [SOMEURL/SOMENUMBER]
06-01 03:21:50.156: I/org.restlet(2653): Starting the internal [HTTP/1.1] client
06-01 03:21:50.236: D/dalvikvm(2653): GC_CONCURRENT freed 1295K, 38% free 8905K/14343K, external 576K/1020K, paused 3ms+4ms
06-01 03:21:50.236: I/org.restlet(2653): Stopping the internal[HTTP/1.1] client
06-01 03:21:50.286: D/dalvikvm(2653): GC_FOR_MALLOC freed 4991K, 61% free 5636K/14343K, external 576K/1020K, paused 32ms
06-01 03:21:50.346: D/dalvikvm(2653): GC_CONCURRENT freed 52K, 53% free 6748K/14343K, external 576K/1020K, paused 2ms+4ms
06-01 03:21:50.386: D/dalvikvm(2653): GC_FOR_MALLOC freed 50K, 43% free 8249K/14343K, external 576K/1020K, paused 30ms
06-01 03:21:50.867: I/global(2653): Loaded time zone names for en_US in 400ms.
06-01 03:21:51.107: RestletTrip(2653): Querying: [SOMEURL/SOMENUMBER]
06-01 03:21:51.127: I/org.restlet(2653): Starting the internal [HTTP/1.1] client
06-01 03:21:51.207: D/dalvikvm(2653): GC_CONCURRENT freed 1290K, 38% free 9006K/14343K, external 576K/1020K, paused 2ms+4ms
06-01 03:21:51.207: I/org.restlet(2653): Stopping the internal[HTTP/1.1] client
06-01 03:21:51.257: D/dalvikvm(2653): GC_FOR_MALLOC freed 4937K, 60% free 5791K/14343K, external 576K/1020K, paused 32ms
06-01 03:21:51.317: D/dalvikvm(2653): GC_CONCURRENT freed 106K, 52% free 6900K/14343K, external 576K/1020K, paused 2ms+4ms
06-01 03:21:51.387: D/dalvikvm(2653): GC_CONCURRENT freed 54K, 42% free 8448K/14343K, external 576K/1020K, paused 3ms+4ms
06-01 03:21:51.868: I/global(2653): Loaded time zone names for en_US in 406ms.
06-01 03:21:52.118: RestletTrip(2653): Querying: [SOMEURL/SOMENUMBER]
06-01 03:21:52.128: I/org.restlet(2653): Starting the internal [HTTP/1.1] client
06-01 03:21:52.218: D/dalvikvm(2653): GC_CONCURRENT freed 1297K, 36% free 9198K/14343K, external 576K/1020K, paused 3ms+3ms
06-01 03:21:52.218: I/org.restlet(2653): Stopping the internal[HTTP/1.1] client

我使用的代码是（为了更快理解而去掉了）：

public List<Trip> getTrips() {

    // All the ids for the different trips
    List<Long> ids = new ArrayList<Long>;
    ids.add(new Long(14));
    ids.add(new Long(45));
    ids.add(new Long(34));
    ids.add(new Long(11));
    ids.add(new Long(33));
    ids.add(new Long(17));

    // All the Trips
    List<Trip> result = new ArrayList<Trip>();

    for (Long tripID : ids) {
        Trip trip = getTrip(tripID);            

        // Add trip to the list
        if (trip != null) {
            result.add(trip);
        }
    }
    return result;
}

public Trip getTrip(ISettings settings, Long tripID) throws GetTripException, NoSuchElementException {

    // Create resource
    final TripsResource tripResource = getClientResource(ServerPaths.getTrip(tripID), TripsResource.class);

    // Get trip from server
    return tripResource.getTrip();
}

我使用的引擎设置是

import org.restlet.engine.Engine;
import org.restlet.ext.httpclient.HttpClientHelper;
import org.restlet.ext.jackson.JacksonConverter;
import org.restlet.ext.json.JsonConverter;
import org.restlet.Client;
import org.restlet.data.Protocol;

protected void setupEngine() {
    final Engine engine = Engine.getInstance();

    engine.getRegisteredClients().add(new HttpClientHelper(new Client(Protocol.HTTP)));
    engine.getRegisteredConverters().add(new JacksonConverter());
    engine.getRegisteredConverters().add(new JsonConverter());
}

因此，由于 GC，检索速度非常慢。如何提高性能？

【问题讨论】：

标签： android performance http restlet

【解决方案1】：

您确实在一遍又一遍地重新创建 HTTP 客户端连接器。

解决方法是创建一个实例：myClient = new Client(Protocol.HTTP);

然后，为您通过 myClientResource.setNext(myClient) 创建的每个 ClientResource 设置它；

顺便说一句，如果您使用的是父级 Restlet 组件和应用程序，这将自动为您完成。

【讨论】：

你能给我提供一个包装资源并调用它的示例代码吗？
或者是否有说明文档的项目？
《Restlet in Action》一书中有这样的例子： System.out.println("\n1) 设置服务客户端资源\n");客户端client = new Client(new Context(), Protocol.HTTP); ClientResource service = new ClientResource("localhost:8111"); service.setNext(client);
我接受了你的回答，因为它回答了我的问题。但是，没有很好的指导如何在Android中使用restlet Restlet Component & Application