org.apache.http.client.cache.HttpCacheEntry Maven / Gradle / Ivy
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* ====================================================================
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* .
*
*/
package org.apache.http.client.cache;
import java.io.Serializable;
import java.util.Collections;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;
import org.apache.http.Header;
import org.apache.http.HttpResponse;
import org.apache.http.ProtocolVersion;
import org.apache.http.StatusLine;
import org.apache.http.annotation.Immutable;
import org.apache.http.message.HeaderGroup;
/**
* Structure used to store an {@link HttpResponse} in a cache. Some entries
* can optionally depend on system resources that may require explicit
* deallocation. In such a case {@link #getResource()} should return a non
* null instance of {@link Resource} that must be deallocated by calling
* {@link Resource#dispose()} method when no longer used.
*
* @since 4.1
*/
@Immutable
public class HttpCacheEntry implements Serializable {
private static final long serialVersionUID = -6300496422359477413L;
private final Date requestDate;
private final Date responseDate;
private final StatusLine statusLine;
private final HeaderGroup responseHeaders;
private final Resource resource;
private final Map variantMap;
/**
* Create a new {@link HttpCacheEntry} with variants.
* @param requestDate
* Date/time when the request was made (Used for age
* calculations)
* @param responseDate
* Date/time that the response came back (Used for age
* calculations)
* @param statusLine
* HTTP status line from origin response
* @param responseHeaders
* Header[] from original HTTP Response
* @param resource representing origin response body
* @param variantMap describing cache entries that are variants
* of this parent entry; this maps a "variant key" (derived
* from the varying request headers) to a "cache key" (where
* in the cache storage the particular variant is located)
*/
public HttpCacheEntry(
final Date requestDate,
final Date responseDate,
final StatusLine statusLine,
final Header[] responseHeaders,
final Resource resource,
final Map variantMap) {
super();
if (requestDate == null) {
throw new IllegalArgumentException("Request date may not be null");
}
if (responseDate == null) {
throw new IllegalArgumentException("Response date may not be null");
}
if (statusLine == null) {
throw new IllegalArgumentException("Status line may not be null");
}
if (responseHeaders == null) {
throw new IllegalArgumentException("Response headers may not be null");
}
if (resource == null) {
throw new IllegalArgumentException("Resource may not be null");
}
this.requestDate = requestDate;
this.responseDate = responseDate;
this.statusLine = statusLine;
this.responseHeaders = new HeaderGroup();
this.responseHeaders.setHeaders(responseHeaders);
this.resource = resource;
this.variantMap = variantMap != null
? new HashMap(variantMap)
: null;
}
/**
* Create a new {@link HttpCacheEntry}.
*
* @param requestDate
* Date/time when the request was made (Used for age
* calculations)
* @param responseDate
* Date/time that the response came back (Used for age
* calculations)
* @param statusLine
* HTTP status line from origin response
* @param responseHeaders
* Header[] from original HTTP Response
* @param resource representing origin response body
*/
public HttpCacheEntry(Date requestDate, Date responseDate, StatusLine statusLine,
Header[] responseHeaders, Resource resource) {
this(requestDate, responseDate, statusLine, responseHeaders, resource,
new HashMap());
}
/**
* Returns the {@link StatusLine} from the origin {@link HttpResponse}.
*/
public StatusLine getStatusLine() {
return this.statusLine;
}
/**
* Returns the {@link ProtocolVersion} from the origin {@link HttpResponse}.
*/
public ProtocolVersion getProtocolVersion() {
return this.statusLine.getProtocolVersion();
}
/**
* Gets the reason phrase from the origin {@link HttpResponse}, for example,
* "Not Modified".
*/
public String getReasonPhrase() {
return this.statusLine.getReasonPhrase();
}
/**
* Returns the HTTP response code from the origin {@link HttpResponse}.
*/
public int getStatusCode() {
return this.statusLine.getStatusCode();
}
/**
* Returns the time the associated origin request was initiated by the
* caching module.
* @return {@link Date}
*/
public Date getRequestDate() {
return requestDate;
}
/**
* Returns the time the origin response was received by the caching module.
* @return {@link Date}
*/
public Date getResponseDate() {
return responseDate;
}
/**
* Returns all the headers that were on the origin response.
*/
public Header[] getAllHeaders() {
return responseHeaders.getAllHeaders();
}
/**
* Returns the first header from the origin response with the given
* name.
*/
public Header getFirstHeader(String name) {
return responseHeaders.getFirstHeader(name);
}
/**
* Gets all the headers with the given name that were on the origin
* response.
*/
public Header[] getHeaders(String name) {
return responseHeaders.getHeaders(name);
}
/**
* Returns the {@link Resource} containing the origin response body.
*/
public Resource getResource() {
return this.resource;
}
/**
* Indicates whether the origin response indicated the associated
* resource had variants (i.e. that the Vary header was set on the
* origin response).
* @return {@code true} if this cached response was a variant
*/
public boolean hasVariants() {
return getFirstHeader(HeaderConstants.VARY) != null;
}
/**
* Returns an index about where in the cache different variants for
* a given resource are stored. This maps "variant keys" to "cache keys",
* where the variant key is derived from the varying request headers,
* and the cache key is the location in the
* {@link org.apache.http.client.cache.HttpCacheStorage} where that
* particular variant is stored. The first variant returned is used as
* the "parent" entry to hold this index of the other variants.
*/
public Map getVariantMap() {
return Collections.unmodifiableMap(variantMap);
}
/**
* Provides a string representation of this instance suitable for
* human consumption.
*/
@Override
public String toString() {
return "[request date=" + this.requestDate + "; response date=" + this.responseDate
+ "; statusLine=" + this.statusLine + "]";
}
}