Java ResponseSource.CACHE属性代码示例

/**
 * Figures out what the response source will be, and opens a socket to that
 * source if necessary. Prepares the request headers and gets ready to start
 * writing the request body if it exists.
 */
public final void sendRequest() throws IOException {
  if (responseSource != null) {
    return;
  }

  prepareRawRequestHeaders();
  initResponseSource();
  OkResponseCache responseCache = client.getOkResponseCache();
  if (responseCache != null) {
    responseCache.trackResponse(responseSource);
  }

  // The raw response source may require the network, but the request
  // headers may forbid network use. In that case, dispose of the network
  // response and use a GATEWAY_TIMEOUT response instead, as specified
  // by http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.9.4.
  if (requestHeaders.isOnlyIfCached() && responseSource.requiresConnection()) {
    if (responseSource == ResponseSource.CONDITIONAL_CACHE) {
      Util.closeQuietly(cachedResponseBody);
    }
    this.responseSource = ResponseSource.CACHE;
    this.cacheResponse = GATEWAY_TIMEOUT_RESPONSE;
    RawHeaders rawResponseHeaders = RawHeaders.fromMultimap(cacheResponse.getHeaders(), true);
    setResponse(new ResponseHeaders(uri, rawResponseHeaders), cacheResponse.getBody());
  }

  if (responseSource.requiresConnection()) {
    sendSocketRequest();
  } else if (connection != null) {
    client.getConnectionPool().recycle(connection);
    connection = null;
  }
}
 

/**
 * Initialize the source for this response. It may be corrected later if the
 * request headers forbids network use.
 */
private void initResponseSource() throws IOException {
  responseSource = ResponseSource.NETWORK;
  if (!policy.getUseCaches()) return;

  OkResponseCache responseCache = client.getOkResponseCache();
  if (responseCache == null) return;

  CacheResponse candidate = responseCache.get(
      uri, method, requestHeaders.getHeaders().toMultimap(false));
  if (candidate == null) return;

  Map<String, List<String>> responseHeadersMap = candidate.getHeaders();
  cachedResponseBody = candidate.getBody();
  if (!acceptCacheResponseType(candidate)
      || responseHeadersMap == null
      || cachedResponseBody == null) {
    Util.closeQuietly(cachedResponseBody);
    return;
  }

  RawHeaders rawResponseHeaders = RawHeaders.fromMultimap(responseHeadersMap, true);
  cachedResponseHeaders = new ResponseHeaders(uri, rawResponseHeaders);
  long now = System.currentTimeMillis();
  this.responseSource = cachedResponseHeaders.chooseResponseSource(now, requestHeaders);
  if (responseSource == ResponseSource.CACHE) {
    this.cacheResponse = candidate;
    setResponse(cachedResponseHeaders, cachedResponseBody);
  } else if (responseSource == ResponseSource.CONDITIONAL_CACHE) {
    this.cacheResponse = candidate;
  } else if (responseSource == ResponseSource.NETWORK) {
    Util.closeQuietly(cachedResponseBody);
  } else {
    throw new AssertionError();
  }
}
 

/**
 * Figures out what the response source will be, and opens a socket to that
 * source if necessary. Prepares the request headers and gets ready to start
 * writing the request body if it exists.
 */
public final void sendRequest() throws IOException {
    if (responseSource != null) {
        return;
    }

    prepareRawRequestHeaders();
    initResponseSource();
    OkResponseCache responseCache = client.getOkResponseCache();
    if (responseCache != null) {
        responseCache.trackResponse(responseSource);
    }

    // The raw response source may require the network, but the request
    // headers may forbid network use. In that case, dispose of the network
    // response and use a GATEWAY_TIMEOUT response instead, as specified
    // by http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.9.4.
    if (requestHeaders.isOnlyIfCached() && responseSource.requiresConnection()) {
        if (responseSource == ResponseSource.CONDITIONAL_CACHE) {
            Util.closeQuietly(cachedResponseBody);
        }
        this.responseSource = ResponseSource.CACHE;
        this.cacheResponse = GATEWAY_TIMEOUT_RESPONSE;
        RawHeaders rawResponseHeaders = RawHeaders.fromMultimap(cacheResponse.getHeaders(), true);
        setResponse(new ResponseHeaders(uri, rawResponseHeaders), cacheResponse.getBody());
    }

    if (responseSource.requiresConnection()) {
        sendSocketRequest();
    } else if (connection != null) {
        client.getConnectionPool().recycle(connection);
        connection = null;
    }
}
 

/**
 * Initialize the source for this response. It may be corrected later if the
 * request headers forbids network use.
 */
private void initResponseSource() throws IOException {
    responseSource = ResponseSource.NETWORK;
    if (!policy.getUseCaches())
        return;

    OkResponseCache responseCache = client.getOkResponseCache();
    if (responseCache == null)
        return;

    CacheResponse candidate = responseCache.get(uri, method, requestHeaders.getHeaders().toMultimap(false));
    if (candidate == null)
        return;

    Map<String, List<String>> responseHeadersMap = candidate.getHeaders();
    cachedResponseBody = candidate.getBody();
    if (!acceptCacheResponseType(candidate) || responseHeadersMap == null || cachedResponseBody == null) {
        Util.closeQuietly(cachedResponseBody);
        return;
    }

    RawHeaders rawResponseHeaders = RawHeaders.fromMultimap(responseHeadersMap, true);
    cachedResponseHeaders = new ResponseHeaders(uri, rawResponseHeaders);
    long now = System.currentTimeMillis();
    this.responseSource = cachedResponseHeaders.chooseResponseSource(now, requestHeaders);
    if (responseSource == ResponseSource.CACHE) {
        this.cacheResponse = candidate;
        setResponse(cachedResponseHeaders, cachedResponseBody);
    } else if (responseSource == ResponseSource.CONDITIONAL_CACHE) {
        this.cacheResponse = candidate;
    } else if (responseSource == ResponseSource.NETWORK) {
        Util.closeQuietly(cachedResponseBody);
    } else {
        throw new AssertionError();
    }
}
 

/** Returns the source to satisfy {@code request} given this cached response. */
public ResponseSource chooseResponseSource(long nowMillis, RequestHeaders request) {
  // If this response shouldn't have been stored, it should never be used
  // as a response source. This check should be redundant as long as the
  // persistence store is well-behaved and the rules are constant.
  if (!isCacheable(request)) {
    return ResponseSource.NETWORK;
  }

  if (request.isNoCache() || request.hasConditions()) {
    return ResponseSource.NETWORK;
  }

  long ageMillis = computeAge(nowMillis);
  long freshMillis = computeFreshnessLifetime();

  if (request.getMaxAgeSeconds() != -1) {
    freshMillis = Math.min(freshMillis, TimeUnit.SECONDS.toMillis(request.getMaxAgeSeconds()));
  }

  long minFreshMillis = 0;
  if (request.getMinFreshSeconds() != -1) {
    minFreshMillis = TimeUnit.SECONDS.toMillis(request.getMinFreshSeconds());
  }

  long maxStaleMillis = 0;
  if (!mustRevalidate && request.getMaxStaleSeconds() != -1) {
    maxStaleMillis = TimeUnit.SECONDS.toMillis(request.getMaxStaleSeconds());
  }

  if (!noCache && ageMillis + minFreshMillis < freshMillis + maxStaleMillis) {
    if (ageMillis + minFreshMillis >= freshMillis) {
      headers.add("Warning", "110 HttpURLConnection \"Response is stale\"");
    }
    long oneDayMillis = 24 * 60 * 60 * 1000L;
    if (ageMillis > oneDayMillis && isFreshnessLifetimeHeuristic()) {
      headers.add("Warning", "113 HttpURLConnection \"Heuristic expiration\"");
    }
    return ResponseSource.CACHE;
  }

  if (lastModified != null) {
    request.setIfModifiedSince(lastModified);
  } else if (servedDate != null) {
    request.setIfModifiedSince(servedDate);
  }

  if (etag != null) {
    request.setIfNoneMatch(etag);
  }

  return request.hasConditions() ? ResponseSource.CONDITIONAL_CACHE : ResponseSource.NETWORK;
}
 

/**
 * Returns the source to satisfy {@code request} given this cached response.
 */
public ResponseSource chooseResponseSource(long nowMillis, RequestHeaders request) {
    // If this response shouldn't have been stored, it should never be used
    // as a response source. This check should be redundant as long as the
    // persistence store is well-behaved and the rules are constant.
    if (!isCacheable(request)) {
        return ResponseSource.NETWORK;
    }

    if (request.isNoCache() || request.hasConditions()) {
        return ResponseSource.NETWORK;
    }

    long ageMillis = computeAge(nowMillis);
    long freshMillis = computeFreshnessLifetime();

    if (request.getMaxAgeSeconds() != -1) {
        freshMillis = Math.min(freshMillis, TimeUnit.SECONDS.toMillis(request.getMaxAgeSeconds()));
    }

    long minFreshMillis = 0;
    if (request.getMinFreshSeconds() != -1) {
        minFreshMillis = TimeUnit.SECONDS.toMillis(request.getMinFreshSeconds());
    }

    long maxStaleMillis = 0;
    if (!mustRevalidate && request.getMaxStaleSeconds() != -1) {
        maxStaleMillis = TimeUnit.SECONDS.toMillis(request.getMaxStaleSeconds());
    }

    if (!noCache && ageMillis + minFreshMillis < freshMillis + maxStaleMillis) {
        if (ageMillis + minFreshMillis >= freshMillis) {
            headers.add("Warning", "110 HttpURLConnection \"Response is stale\"");
        }
        long oneDayMillis = 24 * 60 * 60 * 1000L;
        if (ageMillis > oneDayMillis && isFreshnessLifetimeHeuristic()) {
            headers.add("Warning", "113 HttpURLConnection \"Heuristic expiration\"");
        }
        return ResponseSource.CACHE;
    }

    if (lastModified != null) {
        request.setIfModifiedSince(lastModified);
    } else if (servedDate != null) {
        request.setIfModifiedSince(servedDate);
    }

    if (etag != null) {
        request.setIfNoneMatch(etag);
    }

    return request.hasConditions() ? ResponseSource.CONDITIONAL_CACHE : ResponseSource.NETWORK;
}