com.android.volley.Request Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of library Show documentation
Show all versions of library Show documentation
Volley is a network library from Android source code.
/*
* Copyright (C) 2011 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.android.volley;
import android.net.TrafficStats;
import android.net.Uri;
import android.os.Handler;
import android.os.Looper;
import android.os.SystemClock;
import android.text.TextUtils;
import com.android.volley.VolleyLog.MarkerLog;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.util.Collections;
import java.util.Map;
/**
* Base class for all network requests.
*
* @param The type of parsed response this request expects.
*/
public abstract class Request implements Comparable> {
/**
* Default encoding for POST or PUT parameters. See {@link #getParamsEncoding()}.
*/
private static final String DEFAULT_PARAMS_ENCODING = "UTF-8";
/**
* Supported request methods.
*/
public interface Method {
int DEPRECATED_GET_OR_POST = -1;
int GET = 0;
int POST = 1;
int PUT = 2;
int DELETE = 3;
int HEAD = 4;
int OPTIONS = 5;
int TRACE = 6;
int PATCH = 7;
}
/** An event log tracing the lifetime of this request; for debugging. */
private final MarkerLog mEventLog = MarkerLog.ENABLED ? new MarkerLog() : null;
/**
* Request method of this request. Currently supports GET, POST, PUT, DELETE, HEAD, OPTIONS,
* TRACE, and PATCH.
*/
private final int mMethod;
/** URL of this request. */
private final String mUrl;
/** The redirect url to use for 3xx http responses */
private String mRedirectUrl;
/** Default tag for {@link TrafficStats}. */
private final int mDefaultTrafficStatsTag;
/** Listener interface for errors. */
private final Response.ErrorListener mErrorListener;
/** Sequence number of this request, used to enforce FIFO ordering. */
private Integer mSequence;
/** The request queue this request is associated with. */
private RequestQueue mRequestQueue;
/** Whether or not responses to this request should be cached. */
private boolean mShouldCache = true;
/** Whether or not this request has been canceled. */
private boolean mCanceled = false;
/** Whether or not a response has been delivered for this request yet. */
private boolean mResponseDelivered = false;
// A cheap variant of request tracing used to dump slow requests.
private long mRequestBirthTime = 0;
/** Threshold at which we should log the request (even when debug logging is not enabled). */
private static final long SLOW_REQUEST_THRESHOLD_MS = 3000;
/** The retry policy for this request. */
private RetryPolicy mRetryPolicy;
/**
* When a request can be retrieved from cache but must be refreshed from
* the network, the cache entry will be stored here so that in the event of
* a "Not Modified" response, we can be sure it hasn't been evicted from cache.
*/
private Cache.Entry mCacheEntry = null;
/** An opaque token tagging this request; used for bulk cancellation. */
private Object mTag;
/**
* Creates a new request with the given URL and error listener. Note that
* the normal response listener is not provided here as delivery of responses
* is provided by subclasses, who have a better idea of how to deliver an
* already-parsed response.
*
* @deprecated Use {@link #Request(int, String, com.android.volley.Response.ErrorListener)}.
*/
@Deprecated
public Request(String url, Response.ErrorListener listener) {
this(Method.DEPRECATED_GET_OR_POST, url, listener);
}
/**
* Creates a new request with the given method (one of the values from {@link Method}),
* URL, and error listener. Note that the normal response listener is not provided here as
* delivery of responses is provided by subclasses, who have a better idea of how to deliver
* an already-parsed response.
*/
public Request(int method, String url, Response.ErrorListener listener) {
mMethod = method;
mUrl = url;
mErrorListener = listener;
setRetryPolicy(new DefaultRetryPolicy());
mDefaultTrafficStatsTag = findDefaultTrafficStatsTag(url);
}
/**
* Return the method for this request. Can be one of the values in {@link Method}.
*/
public int getMethod() {
return mMethod;
}
/**
* Set a tag on this request. Can be used to cancel all requests with this
* tag by {@link RequestQueue#cancelAll(Object)}.
*
* @return This Request object to allow for chaining.
*/
public Request setTag(Object tag) {
mTag = tag;
return this;
}
/**
* Returns this request's tag.
* @see Request#setTag(Object)
*/
public Object getTag() {
return mTag;
}
/**
* @return A tag for use with {@link TrafficStats#setThreadStatsTag(int)}
*/
public int getTrafficStatsTag() {
return mDefaultTrafficStatsTag;
}
/**
* @return The hashcode of the URL's host component, or 0 if there is none.
*/
private static int findDefaultTrafficStatsTag(String url) {
if (!TextUtils.isEmpty(url)) {
Uri uri = Uri.parse(url);
if (uri != null) {
String host = uri.getHost();
if (host != null) {
return host.hashCode();
}
}
}
return 0;
}
/**
* Sets the retry policy for this request.
*
* @return This Request object to allow for chaining.
*/
public Request setRetryPolicy(RetryPolicy retryPolicy) {
mRetryPolicy = retryPolicy;
return this;
}
/**
* Adds an event to this request's event log; for debugging.
*/
public void addMarker(String tag) {
if (MarkerLog.ENABLED) {
mEventLog.add(tag, Thread.currentThread().getId());
} else if (mRequestBirthTime == 0) {
mRequestBirthTime = SystemClock.elapsedRealtime();
}
}
/**
* Notifies the request queue that this request has finished (successfully or with error).
*
* Also dumps all events from this request's event log; for debugging.
*/
void finish(final String tag) {
if (mRequestQueue != null) {
mRequestQueue.finish(this);
}
if (MarkerLog.ENABLED) {
final long threadId = Thread.currentThread().getId();
if (Looper.myLooper() != Looper.getMainLooper()) {
// If we finish marking off of the main thread, we need to
// actually do it on the main thread to ensure correct ordering.
Handler mainThread = new Handler(Looper.getMainLooper());
mainThread.post(new Runnable() {
@Override
public void run() {
mEventLog.add(tag, threadId);
mEventLog.finish(this.toString());
}
});
return;
}
mEventLog.add(tag, threadId);
mEventLog.finish(this.toString());
} else {
long requestTime = SystemClock.elapsedRealtime() - mRequestBirthTime;
if (requestTime >= SLOW_REQUEST_THRESHOLD_MS) {
VolleyLog.d("%d ms: %s", requestTime, this.toString());
}
}
}
/**
* Associates this request with the given queue. The request queue will be notified when this
* request has finished.
*
* @return This Request object to allow for chaining.
*/
public Request setRequestQueue(RequestQueue requestQueue) {
mRequestQueue = requestQueue;
return this;
}
/**
* Sets the sequence number of this request. Used by {@link RequestQueue}.
*
* @return This Request object to allow for chaining.
*/
public final Request setSequence(int sequence) {
mSequence = sequence;
return this;
}
/**
* Returns the sequence number of this request.
*/
public final int getSequence() {
if (mSequence == null) {
throw new IllegalStateException("getSequence called before setSequence");
}
return mSequence;
}
/**
* Returns the URL of this request.
*/
public String getUrl() {
return (mRedirectUrl != null) ? mRedirectUrl : mUrl;
}
/**
* Returns the URL of the request before any redirects have occurred.
*/
public String getOriginUrl() {
return mUrl;
}
/**
* Sets the redirect url to handle 3xx http responses.
*/
public void setRedirectUrl(String redirectUrl) {
mRedirectUrl = redirectUrl;
}
/**
* Returns the cache key for this request. By default, this is the URL.
*/
public String getCacheKey() {
return getUrl();
}
/**
* Annotates this request with an entry retrieved for it from cache.
* Used for cache coherency support.
*
* @return This Request object to allow for chaining.
*/
public Request setCacheEntry(Cache.Entry entry) {
mCacheEntry = entry;
return this;
}
/**
* Returns the annotated cache entry, or null if there isn't one.
*/
public Cache.Entry getCacheEntry() {
return mCacheEntry;
}
/**
* Mark this request as canceled. No callback will be delivered.
*/
public void cancel() {
mCanceled = true;
}
/**
* Returns true if this request has been canceled.
*/
public boolean isCanceled() {
return mCanceled;
}
/**
* Returns a list of extra HTTP headers to go along with this request. Can
* throw {@link AuthFailureError} as authentication may be required to
* provide these values.
* @throws AuthFailureError In the event of auth failure
*/
public Map getHeaders() throws AuthFailureError {
return Collections.emptyMap();
}
/**
* Returns a Map of POST parameters to be used for this request, or null if
* a simple GET should be used. Can throw {@link AuthFailureError} as
* authentication may be required to provide these values.
*
* Note that only one of getPostParams() and getPostBody() can return a non-null
* value.
* @throws AuthFailureError In the event of auth failure
*
* @deprecated Use {@link #getParams()} instead.
*/
@Deprecated
protected Map getPostParams() throws AuthFailureError {
return getParams();
}
/**
* Returns which encoding should be used when converting POST parameters returned by
* {@link #getPostParams()} into a raw POST body.
*
* This controls both encodings:
*
* - The string encoding used when converting parameter names and values into bytes prior
* to URL encoding them.
* - The string encoding used when converting the URL encoded parameters into a raw
* byte array.
*
*
* @deprecated Use {@link #getParamsEncoding()} instead.
*/
@Deprecated
protected String getPostParamsEncoding() {
return getParamsEncoding();
}
/**
* @deprecated Use {@link #getBodyContentType()} instead.
*/
@Deprecated
public String getPostBodyContentType() {
return getBodyContentType();
}
/**
* Returns the raw POST body to be sent.
*
* @throws AuthFailureError In the event of auth failure
*
* @deprecated Use {@link #getBody()} instead.
*/
@Deprecated
public byte[] getPostBody() throws AuthFailureError {
// Note: For compatibility with legacy clients of volley, this implementation must remain
// here instead of simply calling the getBody() function because this function must
// call getPostParams() and getPostParamsEncoding() since legacy clients would have
// overridden these two member functions for POST requests.
Map postParams = getPostParams();
if (postParams != null && postParams.size() > 0) {
return encodeParameters(postParams, getPostParamsEncoding());
}
return null;
}
/**
* Returns a Map of parameters to be used for a POST or PUT request. Can throw
* {@link AuthFailureError} as authentication may be required to provide these values.
*
* Note that you can directly override {@link #getBody()} for custom data.
*
* @throws AuthFailureError in the event of auth failure
*/
protected Map getParams() throws AuthFailureError {
return null;
}
/**
* Returns which encoding should be used when converting POST or PUT parameters returned by
* {@link #getParams()} into a raw POST or PUT body.
*
* This controls both encodings:
*
* - The string encoding used when converting parameter names and values into bytes prior
* to URL encoding them.
* - The string encoding used when converting the URL encoded parameters into a raw
* byte array.
*
*/
protected String getParamsEncoding() {
return DEFAULT_PARAMS_ENCODING;
}
public String getBodyContentType() {
return "application/x-www-form-urlencoded; charset=" + getParamsEncoding();
}
/**
* Returns the raw POST or PUT body to be sent.
*
* @throws AuthFailureError in the event of auth failure
*/
public byte[] getBody() throws AuthFailureError {
Map params = getParams();
if (params != null && params.size() > 0) {
return encodeParameters(params, getParamsEncoding());
}
return null;
}
/**
* Converts params into an application/x-www-form-urlencoded encoded string.
*/
private byte[] encodeParameters(Map params, String paramsEncoding) {
StringBuilder encodedParams = new StringBuilder();
try {
for (Map.Entry entry : params.entrySet()) {
encodedParams.append(URLEncoder.encode(entry.getKey(), paramsEncoding));
encodedParams.append('=');
encodedParams.append(URLEncoder.encode(entry.getValue(), paramsEncoding));
encodedParams.append('&');
}
return encodedParams.toString().getBytes(paramsEncoding);
} catch (UnsupportedEncodingException uee) {
throw new RuntimeException("Encoding not supported: " + paramsEncoding, uee);
}
}
/**
* Set whether or not responses to this request should be cached.
*
* @return This Request object to allow for chaining.
*/
public final Request setShouldCache(boolean shouldCache) {
mShouldCache = shouldCache;
return this;
}
/**
* Returns true if responses to this request should be cached.
*/
public final boolean shouldCache() {
return mShouldCache;
}
/**
* Priority values. Requests will be processed from higher priorities to
* lower priorities, in FIFO order.
*/
public enum Priority {
LOW,
NORMAL,
HIGH,
IMMEDIATE
}
/**
* Returns the {@link Priority} of this request; {@link Priority#NORMAL} by default.
*/
public Priority getPriority() {
return Priority.NORMAL;
}
/**
* Returns the socket timeout in milliseconds per retry attempt. (This value can be changed
* per retry attempt if a backoff is specified via backoffTimeout()). If there are no retry
* attempts remaining, this will cause delivery of a {@link TimeoutError} error.
*/
public final int getTimeoutMs() {
return mRetryPolicy.getCurrentTimeout();
}
/**
* Returns the retry policy that should be used for this request.
*/
public RetryPolicy getRetryPolicy() {
return mRetryPolicy;
}
/**
* Mark this request as having a response delivered on it. This can be used
* later in the request's lifetime for suppressing identical responses.
*/
public void markDelivered() {
mResponseDelivered = true;
}
/**
* Returns true if this request has had a response delivered for it.
*/
public boolean hasHadResponseDelivered() {
return mResponseDelivered;
}
/**
* Subclasses must implement this to parse the raw network response
* and return an appropriate response type. This method will be
* called from a worker thread. The response will not be delivered
* if you return null.
* @param response Response from the network
* @return The parsed response, or null in the case of an error
*/
abstract protected Response parseNetworkResponse(NetworkResponse response);
/**
* Subclasses can override this method to parse 'networkError' and return a more specific error.
*
* The default implementation just returns the passed 'networkError'.
*
* @param volleyError the error retrieved from the network
* @return an NetworkError augmented with additional information
*/
protected VolleyError parseNetworkError(VolleyError volleyError) {
return volleyError;
}
/**
* Subclasses must implement this to perform delivery of the parsed
* response to their listeners. The given response is guaranteed to
* be non-null; responses that fail to parse are not delivered.
* @param response The parsed response returned by
* {@link #parseNetworkResponse(NetworkResponse)}
*/
abstract protected void deliverResponse(T response);
/**
* Delivers error message to the ErrorListener that the Request was
* initialized with.
*
* @param error Error details
*/
public void deliverError(VolleyError error) {
if (mErrorListener != null) {
mErrorListener.onErrorResponse(error);
}
}
/**
* Our comparator sorts from high to low priority, and secondarily by
* sequence number to provide FIFO ordering.
*/
@Override
public int compareTo(Request other) {
Priority left = this.getPriority();
Priority right = other.getPriority();
// High-priority requests are "lesser" so they are sorted to the front.
// Equal priorities are sorted by sequence number to provide FIFO ordering.
return left == right ?
this.mSequence - other.mSequence :
right.ordinal() - left.ordinal();
}
@Override
public String toString() {
String trafficStatsTag = "0x" + Integer.toHexString(getTrafficStatsTag());
return (mCanceled ? "[X] " : "[ ] ") + getUrl() + " " + trafficStatsTag + " "
+ getPriority() + " " + mSequence;
}
}