java.lang.Object
- org.apache.hc.client5.http.impl.cache.CachingExecBase
- - org.apache.hc.client5.http.impl.cache.CachingExec

All Implemented Interfaces:

ExecChainHandler
```
class CachingExec
extends CachingExecBase
implements ExecChainHandler
```
Request executor in the request execution chain that is responsible for transparent client-side caching.

The current implementation is conditionally compliant with HTTP/1.1 (meaning all the MUST and MUST NOTs are obeyed), although quite a lot, though not all, of the SHOULDs and SHOULD NOTs are obeyed too.

Folks that would like to experiment with alternative storage backends should look at the HttpCacheStorage interface and the related package documentation there. You may also be interested in the provided EhCache and memcached storage backends.

Further responsibilities such as communication with the opposite endpoint is delegated to the next executor in the request execution chain.

Since:

4.3

Field Summary

Fields
Modifier and Type	Field	Description
`private DefaultCacheRevalidator`	`cacheRevalidator`
`private ConditionalRequestBuilder<org.apache.hc.core5.http.ClassicHttpRequest>`	`conditionalRequestBuilder`
`private static org.slf4j.Logger`	`LOG`
`private HttpCache`	`responseCache`

Fields inherited from class org.apache.hc.client5.http.impl.cache.CachingExecBase
cacheableRequestPolicy, cacheConfig, cacheHits, cacheMisses, cacheUpdates, responseCachingPolicy, responseGenerator, suitabilityChecker, validityPolicy

Constructor Summary

Constructors
Constructor Description

CachingExec(HttpCache cache, DefaultCacheRevalidator cacheRevalidator, CacheConfig config)

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`(package private) org.apache.hc.core5.http.ClassicHttpResponse`	`cacheAndReturnResponse(org.apache.hc.core5.http.HttpHost target, org.apache.hc.core5.http.HttpRequest request, ExecChain.Scope scope, org.apache.hc.core5.http.ClassicHttpResponse backendResponse, java.time.Instant requestSent, java.time.Instant responseReceived)`
`(package private) org.apache.hc.core5.http.ClassicHttpResponse`	`callBackend(org.apache.hc.core5.http.HttpHost target, org.apache.hc.core5.http.ClassicHttpRequest request, ExecChain.Scope scope, ExecChain chain)`
`private static org.apache.hc.core5.http.ClassicHttpResponse`	`convert(SimpleHttpResponse cacheResponse)`
`(package private) org.apache.hc.core5.http.ClassicHttpResponse`	`doExecute(org.apache.hc.core5.http.HttpHost target, org.apache.hc.core5.http.ClassicHttpRequest request, ExecChain.Scope scope, ExecChain chain)`
`org.apache.hc.core5.http.ClassicHttpResponse`	`execute(org.apache.hc.core5.http.ClassicHttpRequest request, ExecChain.Scope scope, ExecChain chain)`	Executes the actual HTTP request.
`(package private) org.apache.hc.core5.http.ClassicHttpResponse`	`handleBackendResponse(org.apache.hc.core5.http.HttpHost target, org.apache.hc.core5.http.ClassicHttpRequest request, ExecChain.Scope scope, java.time.Instant requestDate, java.time.Instant responseDate, org.apache.hc.core5.http.ClassicHttpResponse backendResponse)`
`private org.apache.hc.core5.http.ClassicHttpResponse`	`handleCacheHit(RequestCacheControl requestCacheControl, ResponseCacheControl responseCacheControl, CacheHit hit, org.apache.hc.core5.http.HttpHost target, org.apache.hc.core5.http.ClassicHttpRequest request, ExecChain.Scope scope, ExecChain chain)`
`private org.apache.hc.core5.http.ClassicHttpResponse`	`handleCacheMiss(RequestCacheControl requestCacheControl, CacheHit partialMatch, org.apache.hc.core5.http.HttpHost target, org.apache.hc.core5.http.ClassicHttpRequest request, ExecChain.Scope scope, ExecChain chain)`
`(package private) org.apache.hc.core5.http.ClassicHttpResponse`	`negotiateResponseFromVariants(org.apache.hc.core5.http.HttpHost target, org.apache.hc.core5.http.ClassicHttpRequest request, ExecChain.Scope scope, ExecChain chain, java.util.List<CacheHit> variants)`
`(package private) org.apache.hc.core5.http.ClassicHttpResponse`	`revalidateCacheEntry(ResponseCacheControl responseCacheControl, CacheHit hit, org.apache.hc.core5.http.HttpHost target, org.apache.hc.core5.http.ClassicHttpRequest request, ExecChain.Scope scope, ExecChain chain)`
`(package private) org.apache.hc.core5.http.ClassicHttpResponse`	`revalidateCacheEntryWithFallback(RequestCacheControl requestCacheControl, ResponseCacheControl responseCacheControl, CacheHit hit, org.apache.hc.core5.http.HttpHost target, org.apache.hc.core5.http.ClassicHttpRequest request, ExecChain.Scope scope, ExecChain chain)`
`(package private) org.apache.hc.core5.http.ClassicHttpResponse`	`revalidateCacheEntryWithoutFallback(ResponseCacheControl responseCacheControl, CacheHit hit, org.apache.hc.core5.http.HttpHost target, org.apache.hc.core5.http.ClassicHttpRequest request, ExecChain.Scope scope, ExecChain chain)`

Methods inherited from class org.apache.hc.client5.http.impl.cache.CachingExecBase
clientRequestsOurOptions, generateCachedResponse, generateGatewayTimeout, getCacheHits, getCacheMisses, getCacheUpdates, getCurrentDate, isResponseTooBig, shouldSendNotModifiedResponse, staleIfErrorAppliesTo, storeRequestIfModifiedSinceFor304Response

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

responseCache
```
private final HttpCache responseCache
```

cacheRevalidator

private final DefaultCacheRevalidator cacheRevalidator

conditionalRequestBuilder

private final ConditionalRequestBuilder<org.apache.hc.core5.http.ClassicHttpRequest> conditionalRequestBuilder

LOG

private static final org.slf4j.Logger LOG

Constructor Detail

CachingExec

CachingExec(HttpCache cache,
            DefaultCacheRevalidator cacheRevalidator,
            CacheConfig config)

Method Detail

execute

public org.apache.hc.core5.http.ClassicHttpResponse execute(org.apache.hc.core5.http.ClassicHttpRequest request,
                                                            ExecChain.Scope scope,
                                                            ExecChain chain)
                                                     throws java.io.IOException,
                                                            org.apache.hc.core5.http.HttpException

Description copied from interface: ExecChainHandler

Executes the actual HTTP request. The handler can choose to return a response message or delegate request execution to the next element in the execution chain.

Specified by:: execute in interface ExecChainHandler
Parameters:: request - the actual request.; scope - the execution scope .; chain - the next element in the request execution chain.
Throws:: java.io.IOException; org.apache.hc.core5.http.HttpException

doExecute

org.apache.hc.core5.http.ClassicHttpResponse doExecute(org.apache.hc.core5.http.HttpHost target,
                                                       org.apache.hc.core5.http.ClassicHttpRequest request,
                                                       ExecChain.Scope scope,
                                                       ExecChain chain)
                                                throws java.io.IOException,
                                                       org.apache.hc.core5.http.HttpException

Throws:: java.io.IOException; org.apache.hc.core5.http.HttpException

convert

private static org.apache.hc.core5.http.ClassicHttpResponse convert(SimpleHttpResponse cacheResponse)

callBackend

org.apache.hc.core5.http.ClassicHttpResponse callBackend(org.apache.hc.core5.http.HttpHost target,
                                                         org.apache.hc.core5.http.ClassicHttpRequest request,
                                                         ExecChain.Scope scope,
                                                         ExecChain chain)
                                                  throws java.io.IOException,
                                                         org.apache.hc.core5.http.HttpException

Throws:: java.io.IOException; org.apache.hc.core5.http.HttpException

handleCacheHit

private org.apache.hc.core5.http.ClassicHttpResponse handleCacheHit(RequestCacheControl requestCacheControl,
                                                                    ResponseCacheControl responseCacheControl,
                                                                    CacheHit hit,
                                                                    org.apache.hc.core5.http.HttpHost target,
                                                                    org.apache.hc.core5.http.ClassicHttpRequest request,
                                                                    ExecChain.Scope scope,
                                                                    ExecChain chain)
                                                             throws java.io.IOException,
                                                                    org.apache.hc.core5.http.HttpException

Throws:: java.io.IOException; org.apache.hc.core5.http.HttpException

revalidateCacheEntry

org.apache.hc.core5.http.ClassicHttpResponse revalidateCacheEntry(ResponseCacheControl responseCacheControl,
                                                                  CacheHit hit,
                                                                  org.apache.hc.core5.http.HttpHost target,
                                                                  org.apache.hc.core5.http.ClassicHttpRequest request,
                                                                  ExecChain.Scope scope,
                                                                  ExecChain chain)
                                                           throws java.io.IOException,
                                                                  org.apache.hc.core5.http.HttpException

Throws:: java.io.IOException; org.apache.hc.core5.http.HttpException

revalidateCacheEntryWithoutFallback

org.apache.hc.core5.http.ClassicHttpResponse revalidateCacheEntryWithoutFallback(ResponseCacheControl responseCacheControl,
                                                                                 CacheHit hit,
                                                                                 org.apache.hc.core5.http.HttpHost target,
                                                                                 org.apache.hc.core5.http.ClassicHttpRequest request,
                                                                                 ExecChain.Scope scope,
                                                                                 ExecChain chain)
                                                                          throws org.apache.hc.core5.http.HttpException

Throws:: org.apache.hc.core5.http.HttpException

revalidateCacheEntryWithFallback

org.apache.hc.core5.http.ClassicHttpResponse revalidateCacheEntryWithFallback(RequestCacheControl requestCacheControl,
                                                                              ResponseCacheControl responseCacheControl,
                                                                              CacheHit hit,
                                                                              org.apache.hc.core5.http.HttpHost target,
                                                                              org.apache.hc.core5.http.ClassicHttpRequest request,
                                                                              ExecChain.Scope scope,
                                                                              ExecChain chain)
                                                                       throws org.apache.hc.core5.http.HttpException,
                                                                              java.io.IOException

Throws:: org.apache.hc.core5.http.HttpException; java.io.IOException

handleBackendResponse

org.apache.hc.core5.http.ClassicHttpResponse handleBackendResponse(org.apache.hc.core5.http.HttpHost target,
                                                                   org.apache.hc.core5.http.ClassicHttpRequest request,
                                                                   ExecChain.Scope scope,
                                                                   java.time.Instant requestDate,
                                                                   java.time.Instant responseDate,
                                                                   org.apache.hc.core5.http.ClassicHttpResponse backendResponse)
                                                            throws java.io.IOException

Throws:: java.io.IOException

cacheAndReturnResponse

org.apache.hc.core5.http.ClassicHttpResponse cacheAndReturnResponse(org.apache.hc.core5.http.HttpHost target,
                                                                    org.apache.hc.core5.http.HttpRequest request,
                                                                    ExecChain.Scope scope,
                                                                    org.apache.hc.core5.http.ClassicHttpResponse backendResponse,
                                                                    java.time.Instant requestSent,
                                                                    java.time.Instant responseReceived)
                                                             throws java.io.IOException

Throws:: java.io.IOException

handleCacheMiss

private org.apache.hc.core5.http.ClassicHttpResponse handleCacheMiss(RequestCacheControl requestCacheControl,
                                                                     CacheHit partialMatch,
                                                                     org.apache.hc.core5.http.HttpHost target,
                                                                     org.apache.hc.core5.http.ClassicHttpRequest request,
                                                                     ExecChain.Scope scope,
                                                                     ExecChain chain)
                                                              throws java.io.IOException,
                                                                     org.apache.hc.core5.http.HttpException

Throws:: java.io.IOException; org.apache.hc.core5.http.HttpException

negotiateResponseFromVariants

org.apache.hc.core5.http.ClassicHttpResponse negotiateResponseFromVariants(org.apache.hc.core5.http.HttpHost target,
                                                                           org.apache.hc.core5.http.ClassicHttpRequest request,
                                                                           ExecChain.Scope scope,
                                                                           ExecChain chain,
                                                                           java.util.List<CacheHit> variants)
                                                                    throws java.io.IOException,
                                                                           org.apache.hc.core5.http.HttpException

Throws:: java.io.IOException; org.apache.hc.core5.http.HttpException

Class CachingExec