Java Code Examples for com.android.volley.VolleyLog#DEBUG

@Override
public void onErrorResponse(VolleyError error) {
    int code = DVolleyCode.UNKNOWN_ERROR;
    String description = "";
    if (error.networkResponse != null) {
        code = error.networkResponse.statusCode;
        description = error.networkResponse.toString();
    } else {
        code = DVolleyCode.UNKNOWN_ERROR;
        description = "network timeout";
    }
    if (VolleyLog.DEBUG) {
        Log.d("volley", "[onErrorResponse-> url:" + mRequestWrapper.mUrl + ", params: " + mRequestWrapper.mParamsMap + ", code:" + code + ", msg: " + description + "]");
    }

    onError(code, description);
}
 

/**
 * Prunes the cache to fit the amount of bytes specified.
 * @param neededSpace The amount of bytes we are trying to fit into the cache.
 */
private void pruneIfNeeded(int neededSpace) {
    if ((mTotalSize + neededSpace) < mMaxCacheSizeInBytes) {
        return;
    }
    if (VolleyLog.DEBUG) {
        VolleyLog.v("Pruning old cache entries.");
    }

    long before = mTotalSize;
    int prunedFiles = 0;
    long startTime = SystemClock.elapsedRealtime();

    Iterator<Map.Entry<String, CacheHeader>> iterator = mEntries.entrySet().iterator();
    while (iterator.hasNext()) {
        Map.Entry<String, CacheHeader> entry = iterator.next();
        CacheHeader e = entry.getValue();
        boolean deleted = getFileForKey(e.key).delete();
        if (deleted) {
            mTotalSize -= e.size;
        } else {
           VolleyLog.d("Could not delete cache entry for key=%s, filename=%s",
                   e.key, getFilenameForKey(e.key));
        }
        iterator.remove();
        prunedFiles++;

        if ((mTotalSize + neededSpace) < mMaxCacheSizeInBytes * HYSTERESIS_FACTOR) {
            break;
        }
    }

    if (VolleyLog.DEBUG) {
        VolleyLog.v("pruned %d files, %d bytes, %d ms",
                prunedFiles, (mTotalSize - before), SystemClock.elapsedRealtime() - startTime);
    }
}
 

/**
 * Prunes the cache to fit the amount of bytes specified.
 * @param neededSpace The amount of bytes we are trying to fit into the cache.
 */
private void pruneIfNeeded(int neededSpace) {
    if ((mTotalSize + neededSpace) < mMaxCacheSizeInBytes) {
        return;
    }
    if (VolleyLog.DEBUG) {
        VolleyLog.v("Pruning old cache entries.");
    }

    long before = mTotalSize;
    int prunedFiles = 0;
    long startTime = System.currentTimeMillis();

    Iterator<Map.Entry<String, CacheHeader>> iterator = mEntries.entrySet().iterator();
    while (iterator.hasNext()) {
        Map.Entry<String, CacheHeader> entry = iterator.next();
        CacheHeader e = entry.getValue();
        boolean deleted = getFileForKey(e.key).delete();
        if (deleted) {
            mTotalSize -= e.size;
        } else {
           VolleyLog.d("Could not delete cache entry for key=%s, filename=%s",
                   e.key, getFilenameForKey(e.key));
        }
        iterator.remove();
        prunedFiles++;

        if ((mTotalSize + neededSpace) < mMaxCacheSizeInBytes * HYSTERESIS_FACTOR) {
            break;
        }
    }

    if (VolleyLog.DEBUG) {
        VolleyLog.v("pruned %d files, %d bytes, %d ms",
                prunedFiles, (mTotalSize - before), System.currentTimeMillis() - startTime);
    }
}
 

/**
 * Prunes the cache to fit the amount of bytes specified.
 * @param neededSpace The amount of bytes we are trying to fit into the cache.
 */
private void pruneIfNeeded(int neededSpace) {
    if ((mTotalSize + neededSpace) < mMaxCacheSizeInBytes) {
        return;
    }
    if (VolleyLog.DEBUG) {
        VolleyLog.v("Pruning old cache entries.");
    }

    long before = mTotalSize;
    int prunedFiles = 0;
    long startTime = SystemClock.elapsedRealtime();

    Iterator<Map.Entry<String, CacheHeader>> iterator = mEntries.entrySet().iterator();
    while (iterator.hasNext()) {
        Map.Entry<String, CacheHeader> entry = iterator.next();
        CacheHeader e = entry.getValue();
        boolean deleted = getFileForKey(e.key).delete();
        if (deleted) {
            mTotalSize -= e.size;
        } else {
           VolleyLog.d("Could not delete cache entry for key=%s, filename=%s",
                   e.key, getFilenameForKey(e.key));
        }
        iterator.remove();
        prunedFiles++;

        if ((mTotalSize + neededSpace) < mMaxCacheSizeInBytes * HYSTERESIS_FACTOR) {
            break;
        }
    }

    if (VolleyLog.DEBUG) {
        VolleyLog.v("pruned %d files, %d bytes, %d ms",
                prunedFiles, (mTotalSize - before), SystemClock.elapsedRealtime() - startTime);
    }
}
 

@Override
public void onCreate() {
    super.onCreate();

    OkVolley.getInstance().init(this)
            .setUserAgent(OkVolley.generateUserAgent(this))
            .trustAllCerts();

    VolleyLog.DEBUG = BuildConfig.DEBUG;

}
 

/**
 * Write the name/value pair as form data to the request body
 * <p/>
 * The values specified will be URL-encoded and sent with the
 * 'application/x-www-form-urlencoded' content-type
 *
 * @param name
 * @param value
 * @param charset
 * @return this request
 */
public OkRequest<T> form(final String name, final String value, String charset) {
    final boolean first = !mForm;
    if (first) {
        contentType(PROTOCOL_CONTENT_TYPE_FORM);
        mForm = true;

    }
    charset = getValidCharset(charset);

    openOutput();
    if (!first) {
        mOutput.write('&');
    }
    try {
        if (VolleyLog.DEBUG) {
            VolleyLog.d("name=%1$s, value=%2$s", name, value);
        }
        mOutput.write(URLEncoder.encode(name, charset));
        mOutput.write("=");
        if (value != null) {
            mOutput.write(URLEncoder.encode(value, charset));
        }
    } catch (IOException e) {
        //Do Nothing
    }


    return this;
}
 

/**
 * Prunes the cache to fit the amount of bytes specified.
 * @param neededSpace The amount of bytes we are trying to fit into the cache.
 */
private void pruneIfNeeded(int neededSpace) {
    if ((mTotalSize + neededSpace) < mMaxCacheSizeInBytes) {
        return;
    }
    if (VolleyLog.DEBUG) {
        VolleyLog.v("Pruning old cache entries.");
    }

    long before = mTotalSize;
    int prunedFiles = 0;
    long startTime = SystemClock.elapsedRealtime();

    Iterator<Map.Entry<String, CacheHeader>> iterator = mEntries.entrySet().iterator();
    while (iterator.hasNext()) {
        Map.Entry<String, CacheHeader> entry = iterator.next();
        CacheHeader e = entry.getValue();
        boolean deleted = getFileForKey(e.key).delete();
        if (deleted) {
            mTotalSize -= e.size;
        } else {
           VolleyLog.d("Could not delete cache entry for key=%s, filename=%s",
                   e.key, getFilenameForKey(e.key));
        }
        iterator.remove();
        prunedFiles++;

        if ((mTotalSize + neededSpace) < mMaxCacheSizeInBytes * HYSTERESIS_FACTOR) {
            break;
        }
    }

    if (VolleyLog.DEBUG) {
        VolleyLog.v("pruned %d files, %d bytes, %d ms",
                prunedFiles, (mTotalSize - before), SystemClock.elapsedRealtime() - startTime);
    }
}
 

/**
 * Prunes the cache to fit the amount of bytes specified.
 * @param neededSpace The amount of bytes we are trying to fit into the cache.
 */
private void pruneIfNeeded(int neededSpace) {
    if ((mTotalSize + neededSpace) < mMaxCacheSizeInBytes) {
        return;
    }
    if (VolleyLog.DEBUG) {
        VolleyLog.v("Pruning old cache entries.");
    }

    long before = mTotalSize;
    int prunedFiles = 0;
    long startTime = SystemClock.elapsedRealtime();

    Iterator<Map.Entry<String, CacheHeader>> iterator = mEntries.entrySet().iterator();
    while (iterator.hasNext()) {
        Map.Entry<String, CacheHeader> entry = iterator.next();
        CacheHeader e = entry.getValue();
        boolean deleted = getFileForKey(e.key).delete();
        if (deleted) {
            mTotalSize -= e.size;
        } else {
           VolleyLog.d("Could not delete cache entry for key=%s, filename=%s",
                   e.key, getFilenameForKey(e.key));
        }
        iterator.remove();
        prunedFiles++;

        if ((mTotalSize + neededSpace) < mMaxCacheSizeInBytes * HYSTERESIS_FACTOR) {
            break;
        }
    }

    if (VolleyLog.DEBUG) {
        VolleyLog.v("pruned %d files, %d bytes, %d ms",
                prunedFiles, (mTotalSize - before), SystemClock.elapsedRealtime() - startTime);
    }
}
 

/**
 * Prunes the cache to fit the amount of bytes specified.
 * @param neededSpace The amount of bytes we are trying to fit into the cache.
 */
private void pruneIfNeeded(int neededSpace) {
    if ((mTotalSize + neededSpace) < mMaxCacheSizeInBytes) {
        return;
    }
    if (VolleyLog.DEBUG) {
        VolleyLog.v("Pruning old cache entries.");
    }

    long before = mTotalSize;
    int prunedFiles = 0;
    long startTime = SystemClock.elapsedRealtime();

    Iterator<Map.Entry<String, CacheHeader>> iterator = mEntries.entrySet().iterator();
    while (iterator.hasNext()) {
        Map.Entry<String, CacheHeader> entry = iterator.next();
        CacheHeader e = entry.getValue();
        boolean deleted = getFileForKey(e.key).delete();
        if (deleted) {
            mTotalSize -= e.size;
        } else {
           VolleyLog.d("Could not delete cache entry for key=%s, filename=%s",
                   e.key, getFilenameForKey(e.key));
        }
        iterator.remove();
        prunedFiles++;

        if ((mTotalSize + neededSpace) < mMaxCacheSizeInBytes * HYSTERESIS_FACTOR) {
            break;
        }
    }

    if (VolleyLog.DEBUG) {
        VolleyLog.v("pruned %d files, %d bytes, %d ms",
                prunedFiles, (mTotalSize - before), SystemClock.elapsedRealtime() - startTime);
    }
}
 

/**
 * Prunes the cache to fit the amount of bytes specified.
 * @param neededSpace The amount of bytes we are trying to fit into the cache.
 */
private void pruneIfNeeded(int neededSpace) {
    if ((mTotalSize + neededSpace) < mMaxCacheSizeInBytes) {
        return;
    }
    if (VolleyLog.DEBUG) {
        VolleyLog.v("Pruning old cache entries.");
    }

    long before = mTotalSize;
    int prunedFiles = 0;
    long startTime = SystemClock.elapsedRealtime();

    Iterator<Map.Entry<String, CacheHeader>> iterator = mEntries.entrySet().iterator();
    while (iterator.hasNext()) {
        Map.Entry<String, CacheHeader> entry = iterator.next();
        CacheHeader e = entry.getValue();
        boolean deleted = getFileForKey(e.key).delete();
        if (deleted) {
            mTotalSize -= e.size;
        } else {
           VolleyLog.d("Could not delete cache entry for key=%s, filename=%s",
                   e.key, getFilenameForKey(e.key));
        }
        iterator.remove();
        prunedFiles++;

        if ((mTotalSize + neededSpace) < mMaxCacheSizeInBytes * HYSTERESIS_FACTOR) {
            break;
        }
    }

    if (VolleyLog.DEBUG) {
        VolleyLog.v("pruned %d files, %d bytes, %d ms",
                prunedFiles, (mTotalSize - before), SystemClock.elapsedRealtime() - startTime);
    }
}
 

/**
 * Prunes the cache to fit the amount of bytes specified.
 * @param neededSpace The amount of bytes we are trying to fit into the cache.
 */
private void pruneIfNeeded(int neededSpace) {
    if ((mTotalSize + neededSpace) < mMaxCacheSizeInBytes) {
        return;
    }
    if (VolleyLog.DEBUG) {
        VolleyLog.v("Pruning old cache entries.");
    }

    long before = mTotalSize;
    int prunedFiles = 0;
    long startTime = SystemClock.elapsedRealtime();

    Iterator<Map.Entry<String, CacheHeader>> iterator = mEntries.entrySet().iterator();
    while (iterator.hasNext()) {
        Map.Entry<String, CacheHeader> entry = iterator.next();
        CacheHeader e = entry.getValue();
        boolean deleted = getFileForKey(e.key).delete();
        if (deleted) {
            mTotalSize -= e.size;
        } else {
           VolleyLog.d("Could not delete cache entry for key=%s, filename=%s",
                   e.key, getFilenameForKey(e.key));
        }
        iterator.remove();
        prunedFiles++;

        if ((mTotalSize + neededSpace) < mMaxCacheSizeInBytes * HYSTERESIS_FACTOR) {
            break;
        }
    }

    if (VolleyLog.DEBUG) {
        VolleyLog.v("pruned %d files, %d bytes, %d ms",
                prunedFiles, (mTotalSize - before), SystemClock.elapsedRealtime() - startTime);
    }
}
 

public void onCreate() {
    super.onCreate();
    width = ScreenUtil.getWidth(this);
    height = ScreenUtil.getHeight(this);
    density = ScreenUtil.getDensity(this);
    System.out.println(width);
    System.out.println(height);
    System.out.println(density);

    VolleyLog.DEBUG = true;
}
 

/**
 * Prunes the cache to fit the amount of bytes specified.
 * @param neededSpace The amount of bytes we are trying to fit into the cache.
 */
private void pruneIfNeeded(int neededSpace) {
    if ((mTotalSize + neededSpace) < mMaxCacheSizeInBytes) {
        return;
    }
    if (VolleyLog.DEBUG) {
        VolleyLog.v("Pruning old cache entries.");
    }

    long before = mTotalSize;
    int prunedFiles = 0;
    long startTime = SystemClock.elapsedRealtime();

    Iterator<Map.Entry<String, CacheHeader>> iterator = mEntries.entrySet().iterator();
    while (iterator.hasNext()) {
        Map.Entry<String, CacheHeader> entry = iterator.next();
        CacheHeader e = entry.getValue();
        boolean deleted = getFileForKey(e.key).delete();
        if (deleted) {
            mTotalSize -= e.size;
        } else {
           VolleyLog.d("Could not delete cache entry for key=%s, filename=%s",
                   e.key, getFilenameForKey(e.key));
        }
        iterator.remove();
        prunedFiles++;

        if ((mTotalSize + neededSpace) < mMaxCacheSizeInBytes * HYSTERESIS_FACTOR) {
            break;
        }
    }

    if (VolleyLog.DEBUG) {
        VolleyLog.v("pruned %d files, %d bytes, %d ms",
                prunedFiles, (mTotalSize - before), SystemClock.elapsedRealtime() - startTime);
    }
}
 

/**
 * Prunes the cache to fit the amount of bytes specified.
 * @param neededSpace The amount of bytes we are trying to fit into the cache.
 */
private void pruneIfNeeded(int neededSpace) {
    if ((mTotalSize + neededSpace) < mMaxCacheSizeInBytes) {
        return;
    }
    if (VolleyLog.DEBUG) {
        VolleyLog.v("Pruning old cache entries.");
    }

    long before = mTotalSize;
    int prunedFiles = 0;
    long startTime = SystemClock.elapsedRealtime();

    Iterator<Map.Entry<String, CacheHeader>> iterator = mEntries.entrySet().iterator();
    while (iterator.hasNext()) {
        Map.Entry<String, CacheHeader> entry = iterator.next();
        CacheHeader e = entry.getValue();
        boolean deleted = getFileForKey(e.key).delete();
        if (deleted) {
            mTotalSize -= e.size;
        } else {
           VolleyLog.d("Could not delete cache entry for key=%s, filename=%s",
                   e.key, getFilenameForKey(e.key));
        }
        iterator.remove();
        prunedFiles++;

        if ((mTotalSize + neededSpace) < mMaxCacheSizeInBytes * HYSTERESIS_FACTOR) {
            break;
        }
    }

    if (VolleyLog.DEBUG) {
        VolleyLog.v("pruned %d files, %d bytes, %d ms",
                prunedFiles, (mTotalSize - before), SystemClock.elapsedRealtime() - startTime);
    }
}
 

/**
 * Prunes the cache to fit the amount of bytes specified.
 * @param neededSpace The amount of bytes we are trying to fit into the cache.
 */
private void pruneIfNeeded(int neededSpace) {
    if ((mTotalSize + neededSpace) < mMaxCacheSizeInBytes) {
        return;
    }
    if (VolleyLog.DEBUG) {
        VolleyLog.v("Pruning old cache entries.");
    }

    long before = mTotalSize;
    int prunedFiles = 0;
    long startTime = SystemClock.elapsedRealtime();

    Iterator<Map.Entry<String, CacheHeader>> iterator = mEntries.entrySet().iterator();
    while (iterator.hasNext()) {
        Map.Entry<String, CacheHeader> entry = iterator.next();
        CacheHeader e = entry.getValue();
        boolean deleted = getFileForKey(e.key).delete();
        if (deleted) {
            mTotalSize -= e.size;
        } else {
           VolleyLog.d("Could not delete cache entry for key=%s, filename=%s",
                   e.key, getFilenameForKey(e.key));
        }
        iterator.remove();
        prunedFiles++;

        if ((mTotalSize + neededSpace) < mMaxCacheSizeInBytes * HYSTERESIS_FACTOR) {
            break;
        }
    }

    if (VolleyLog.DEBUG) {
        VolleyLog.v("pruned %d files, %d bytes, %d ms",
                prunedFiles, (mTotalSize - before), SystemClock.elapsedRealtime() - startTime);
    }
}
 

/** Prunes the cache to fit the maximum size. */
private void pruneIfNeeded() {
    if (mTotalSize < mMaxCacheSizeInBytes) {
        return;
    }
    if (VolleyLog.DEBUG) {
        VolleyLog.v("Pruning old cache entries.");
    }

    long before = mTotalSize;
    int prunedFiles = 0;
    long startTime = SystemClock.elapsedRealtime();

    Iterator<Map.Entry<String, CacheHeader>> iterator = mEntries.entrySet().iterator();
    while (iterator.hasNext()) {
        Map.Entry<String, CacheHeader> entry = iterator.next();
        CacheHeader e = entry.getValue();
        boolean deleted = getFileForKey(e.key).delete();
        if (deleted) {
            mTotalSize -= e.size;
        } else {
            VolleyLog.d(
                    "Could not delete cache entry for key=%s, filename=%s",
                    e.key, getFilenameForKey(e.key));
        }
        iterator.remove();
        prunedFiles++;

        if (mTotalSize < mMaxCacheSizeInBytes * DiskBasedCacheUtility.HYSTERESIS_FACTOR) {
            break;
        }
    }

    if (VolleyLog.DEBUG) {
        VolleyLog.v(
                "pruned %d files, %d bytes, %d ms",
                prunedFiles, (mTotalSize - before), SystemClock.elapsedRealtime() - startTime);
    }
}
 

/**
     * perform the request
     *
     * @param request           request
     * @param additionalHeaders headers
     * @return http response
     * @throws java.io.IOException
     * @throws com.android.volley.AuthFailureError
     */
    @Override
    public Response performRequest(Request<?> request,
                                   Map<String, String> additionalHeaders) throws IOException, AuthFailureError {


        String url = request.getUrl();
        HashMap<String, String> map = new HashMap<String, String>();
        map.putAll(request.getHeaders());
        map.putAll(additionalHeaders);
        if (mUrlRewriter != null) {
            String rewritten = mUrlRewriter.rewriteUrl(url);
            if (rewritten == null) {
                throw new IOException("URL blocked by rewriter: " + url);
            }
            url = rewritten;
        }

        com.squareup.okhttp.Request.Builder builder = new com.squareup.okhttp.Request.Builder();
        builder.url(url);

        for (String headerName : map.keySet()) {
            builder.header(headerName, map.get(headerName));
//            connection.addRequestProperty(headerName, map.get(headerName));
            if (VolleyLog.DEBUG) {
                // print header message
                VolleyLog.d("RequestHeader: %1$s:%2$s", headerName, map.get(headerName));
            }
        }
        setConnectionParametersForRequest(builder, request);
        // Initialize HttpResponse with data from the okhttp.
        Response okHttpResponse = mClient.newCall(builder.build()).execute();

        int responseCode = okHttpResponse.code();
        if (responseCode == -1) {
            // -1 is returned by getResponseCode() if the response code could not be retrieved.
            // Signal to the caller that something was wrong with the connection.
            throw new IOException("Could not retrieve response code from HttpUrlConnection.");
        }
        return okHttpResponse;
    }
 

static void setConnectionParametersForRequest(com.squareup.okhttp.Request.Builder builder,
                                              Request<?> request) throws IOException, AuthFailureError {

    byte[] postBody = null;
    if (VolleyLog.DEBUG) {
        VolleyLog.d("request.method = %1$s", request.getMethod());
    }
    switch (request.getMethod()) {
        case Method.DEPRECATED_GET_OR_POST:
            // This is the deprecated way that needs to be handled for backwards compatibility.
            // If the request's post body is null, then the assumption is that the request is
            // GET.  Otherwise, it is assumed that the request is a POST.
            postBody = request.getBody();
            if (postBody != null) {
                // Prepare output. There is no need to set Content-Length explicitly,
                // since this is handled by HttpURLConnection using the size of the prepared
                // output stream.
                builder.post(RequestBody.create(MediaType.parse(request.getBodyContentType()), postBody));
                if (VolleyLog.DEBUG) {
                    VolleyLog.d("RequestHeader: %1$s:%2$s", OkRequest.HEADER_CONTENT_TYPE, request.getPostBodyContentType());
                }
            } else {
                builder.get();
            }
            break;
        case Method.GET:
            // Not necessary to set the request method because connection defaults to GET but
            // being explicit here.
            builder.get();
            break;
        case Method.DELETE:
            builder.delete();
            break;
        case Method.POST:
            postBody = request.getBody();
            if (postBody == null) {
                builder.post(RequestBody.create(MediaType.parse(request.getBodyContentType()), ""));
            } else {
                builder.post(RequestBody.create(MediaType.parse(request.getBodyContentType()), postBody));
            }
            if (VolleyLog.DEBUG) {
                VolleyLog.d("RequestHeader: %1$s:%2$s", OkRequest.HEADER_CONTENT_TYPE, request.getBodyContentType());
            }
            break;
        case Method.PUT:
            postBody = request.getBody();
            if (postBody == null) {
                builder.put(RequestBody.create(MediaType.parse(request.getBodyContentType()), ""));
            } else {
                builder.put(RequestBody.create(MediaType.parse(request.getBodyContentType()), postBody));
            }
            if (VolleyLog.DEBUG) {
                VolleyLog.d("RequestHeader: %1$s:%2$s", OkRequest.HEADER_CONTENT_TYPE, request.getBodyContentType());
            }
            break;
        case Method.HEAD:
            builder.head();
            break;
        case Method.PATCH:
            postBody = request.getBody();
            if (postBody == null) {
                builder.patch(RequestBody.create(MediaType.parse(request.getBodyContentType()), ""));
            } else {
                builder.patch(RequestBody.create(MediaType.parse(request.getBodyContentType()), postBody));
            }
            if (VolleyLog.DEBUG) {
                VolleyLog.d("RequestHeader: %1$s:%2$s", OkRequest.HEADER_CONTENT_TYPE, request.getBodyContentType());
            }
            break;
        default:
            throw new IllegalStateException("Unknown method type.");
    }


}
 

/**
 * Prunes the cache to fit the amount of bytes specified.
 *
 * @param neededSpace The amount of bytes we are trying to fit into the cache.
 */
/*
 * 如果
 * 1.当前的容量 + 需要放入缓存容量 < 最大容量的时候 就返回
 * 2.当前的容量 + 需要放入缓存容量 > 最大容量的时候：
 *   需要删除 最少访问的数据最为代价，一直删除到能容纳此次需要添加的缓存的容量为止
 */
private void pruneIfNeeded(int neededSpace) {
    if ((mTotalSize + neededSpace) < mMaxCacheSizeInBytes) {
        return;
    }
    if (VolleyLog.DEBUG) {
        VolleyLog.v("Pruning old cache entries.");
    }

    long before = mTotalSize;
    int prunedFiles = 0;
    long startTime = SystemClock.elapsedRealtime();
    /*
     * 遍历内存缓存的内容
     * 由于这个 Map 是 LinkedHashMap 并且 accessOrder 设置为 true
     * 所以这个 Map 实现了 LRU 的机制，根据访问顺序，数据会进行调整，最少访问的数据放在首部
     */
    Iterator<Map.Entry<String, CacheHeader>> iterator = mEntries.entrySet().iterator();
    while (iterator.hasNext()) {
        // 首部的数据 是 最少访问的
        Map.Entry<String, CacheHeader> entry = iterator.next();
        CacheHeader e = entry.getValue();
        // 缓存溢出的时候，优先被删除，腾出空间
        boolean deleted = getFileForKey(e.key).delete();
        // 删除后 总容量进行调整
        if (deleted) {
            mTotalSize -= e.size;
        } else {
            VolleyLog.d("Could not delete cache entry for key=%s, filename=%s", e.key,
                    getFilenameForKey(e.key));
        }
        iterator.remove();
        prunedFiles++;

        /*
         * 此时，判断删除一个 最少访问数据后的的容量 + 需要添加缓存的容量 是否 小于 扩容容量
         * 这里 扩容容量 = 最大容量+负载因子 = ( 最大容量*90% )
         * 超了的话 继续删除下一个最少访问的数据（ 还是首部数据 ）
         * 没超的话 表示已经腾出足够空间，足够容纳 需要添加的缓存
         */
        if ((mTotalSize + neededSpace) < mMaxCacheSizeInBytes * HYSTERESIS_FACTOR) {
            break;
        }
    }

    if (VolleyLog.DEBUG) {
        VolleyLog.v("pruned %d files, %d bytes, %d ms", prunedFiles, (mTotalSize - before),
                SystemClock.elapsedRealtime() - startTime);
    }
}
 

/**
 * Adds a Request to the dispatch queue.
 *
 * @param request The request to service
 * @return The passed-in request
 */
public BallRequest add(BallRequest request) {
    // Tag the request as belonging to this queue and add it to the set of current requests.
    request.setRequestQueue(this);
    synchronized (mCurrentRequests) {
        mCurrentRequests.add(request);
    }

    // Process requests in the order they are added.
    request.setSequence(getSequenceNumber());
    request.addMarker("add-to-queue");

    // nothing
    if (!request.shouldProcessLocal() && !request.shouldProcessNetwork()) {
        return request;
    }

    // local only
    if (request.shouldProcessLocal() && !request.shouldProcessNetwork()) {
        mLocalQueue.add(request);
        return request;
    }

    // network

    // no cache no local
    if (!request.shouldCache() && !request.shouldProcessLocal()) {
        mNetworkQueue.add(request);
        return request;
    }

    // network with local
    if (request.shouldProcessLocal()) {
        mLocalQueue.add(request);
    }

    // network without cache, add to network directly
    if (!request.shouldCache()) {
        mNetworkQueue.add(request);
    }
    //network with cache
    else {
        // Insert request into stage if there's already a request with the same cache key in flight.
        synchronized (mWaitingRequests) {
            String cacheKey = request.getCacheKey();
            if (mWaitingRequests.containsKey(cacheKey)) {
                // There is already a request in flight. Queue up.
                Queue<BallRequest> stagedRequests = mWaitingRequests.get(cacheKey);
                if (stagedRequests == null) {
                    stagedRequests = new LinkedList<BallRequest>();
                }
                stagedRequests.add(request);
                mWaitingRequests.put(cacheKey, stagedRequests);
                if (VolleyLog.DEBUG) {
                    VolleyLog.v("Request for cacheKey=%s is in flight, putting on hold.", cacheKey);
                }
            } else {
                // Insert 'null' queue for this cacheKey, indicating there is now a request in
                // flight.
                mWaitingRequests.put(cacheKey, null);
                mCacheQueue.add(request);
            }

        }
    }

    return request;
}