Class CachingExec

  • All Implemented Interfaces:
    org.apache.http.impl.execchain.ClientExecChain

    @Contract(threading=SAFE_CONDITIONAL)
    public class CachingExec
    extends java.lang.Object
    implements org.apache.http.impl.execchain.ClientExecChain

    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
    • Constructor Summary

      Constructors 
      Constructor Description
      CachingExec​(org.apache.http.impl.execchain.ClientExecChain backend)  
      CachingExec​(org.apache.http.impl.execchain.ClientExecChain backend, ResourceFactory resourceFactory, HttpCacheStorage storage, CacheConfig config)  
      CachingExec​(org.apache.http.impl.execchain.ClientExecChain backend, org.apache.http.impl.client.cache.HttpCache cache, CacheConfig config)  
      CachingExec​(org.apache.http.impl.execchain.ClientExecChain backend, org.apache.http.impl.client.cache.HttpCache cache, CacheConfig config, org.apache.http.impl.client.cache.AsynchronousValidator asynchRevalidator)  
    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      org.apache.http.client.methods.CloseableHttpResponse execute​(org.apache.http.conn.routing.HttpRoute route, org.apache.http.client.methods.HttpRequestWrapper request)  
      org.apache.http.client.methods.CloseableHttpResponse execute​(org.apache.http.conn.routing.HttpRoute route, org.apache.http.client.methods.HttpRequestWrapper request, org.apache.http.client.protocol.HttpClientContext context)  
      org.apache.http.client.methods.CloseableHttpResponse execute​(org.apache.http.conn.routing.HttpRoute route, org.apache.http.client.methods.HttpRequestWrapper request, org.apache.http.client.protocol.HttpClientContext context, org.apache.http.client.methods.HttpExecutionAware execAware)  
      long getCacheHits()
      Reports the number of times that the cache successfully responded to an HttpRequest without contacting the origin server.
      long getCacheMisses()
      Reports the number of times that the cache contacted the origin server because it had no appropriate response cached.
      long getCacheUpdates()
      Reports the number of times that the cache was able to satisfy a response by revalidating an existing but stale cache entry.
      boolean supportsRangeAndContentRangeHeaders()
      Reports whether this CachingHttpClient implementation supports byte-range requests as specified by the Range and Content-Range headers.
      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    • Constructor Detail

      • CachingExec

        public CachingExec​(org.apache.http.impl.execchain.ClientExecChain backend,
                           org.apache.http.impl.client.cache.HttpCache cache,
                           CacheConfig config)
      • CachingExec

        public CachingExec​(org.apache.http.impl.execchain.ClientExecChain backend,
                           org.apache.http.impl.client.cache.HttpCache cache,
                           CacheConfig config,
                           org.apache.http.impl.client.cache.AsynchronousValidator asynchRevalidator)
      • CachingExec

        public CachingExec​(org.apache.http.impl.execchain.ClientExecChain backend)
    • Method Detail

      • getCacheHits

        public long getCacheHits()
        Reports the number of times that the cache successfully responded to an HttpRequest without contacting the origin server.
        Returns:
        the number of cache hits
      • getCacheMisses

        public long getCacheMisses()
        Reports the number of times that the cache contacted the origin server because it had no appropriate response cached.
        Returns:
        the number of cache misses
      • getCacheUpdates

        public long getCacheUpdates()
        Reports the number of times that the cache was able to satisfy a response by revalidating an existing but stale cache entry.
        Returns:
        the number of cache revalidations
      • execute

        public org.apache.http.client.methods.CloseableHttpResponse execute​(org.apache.http.conn.routing.HttpRoute route,
                                                                            org.apache.http.client.methods.HttpRequestWrapper request)
                                                                     throws java.io.IOException,
                                                                            org.apache.http.HttpException
        Throws:
        java.io.IOException
        org.apache.http.HttpException
      • execute

        public org.apache.http.client.methods.CloseableHttpResponse execute​(org.apache.http.conn.routing.HttpRoute route,
                                                                            org.apache.http.client.methods.HttpRequestWrapper request,
                                                                            org.apache.http.client.protocol.HttpClientContext context)
                                                                     throws java.io.IOException,
                                                                            org.apache.http.HttpException
        Throws:
        java.io.IOException
        org.apache.http.HttpException
      • execute

        public org.apache.http.client.methods.CloseableHttpResponse execute​(org.apache.http.conn.routing.HttpRoute route,
                                                                            org.apache.http.client.methods.HttpRequestWrapper request,
                                                                            org.apache.http.client.protocol.HttpClientContext context,
                                                                            org.apache.http.client.methods.HttpExecutionAware execAware)
                                                                     throws java.io.IOException,
                                                                            org.apache.http.HttpException
        Specified by:
        execute in interface org.apache.http.impl.execchain.ClientExecChain
        Throws:
        java.io.IOException
        org.apache.http.HttpException
      • supportsRangeAndContentRangeHeaders

        public boolean supportsRangeAndContentRangeHeaders()
        Reports whether this CachingHttpClient implementation supports byte-range requests as specified by the Range and Content-Range headers.
        Returns:
        true if byte-range requests are supported