ResponseCache in java is used for constructing implementation of URLConnection caches, and it nominates which resource has to be cached and up to what time duration a resource needed to be cached.
An instance of ResponseCache can be created using the system by doing :
ResponseCache.setDefault(ResponseCache)
The instance created by using the above statement will call an object of ResponseCache in order to :
- For storing resource data that has been which has been retrieved from an external source into the cache.
- For fetching a resource that has been stored in the cache on request.
- Response cache can be imported through java.net package
java.net.ResponseCache
Methods of ResponseCache class :
| Method | Description |
|---|---|
| get(URI uri, String rqstMethod, Map<String,List<String> > rqstHeaders) | This method is used for retrieving the cached response depending upon the requesting URI, request method and request headers. |
| getDefault() | This method is used for retrieving the system-wide cache response. |
| put(URI uri, URLConnection conn) | The protocol handler calls this method whenever a resource has been retrieved and the ResponseCache must decide whether to store the resource in its cache. |
| setDefault(ResponseCache responseCache) | This method is used to set or unset the system-wide cache |
Applications of ResponseCache class : Â Â
1. In the java.net package, ResponseCache is used for implementing for caching of resources for various network applications such as :
- File Transfer
- Remote Terminal Access
- Loading web pages
java.net.ResponseCache
2. In java.net, ResponseCache is applied in fetching out system-wide response cache.
public static ResponseCache.getDefault()
3. In java.net, ResponseCcahe is used in setting or unsetting out the system-wide cache.
public static void ResponseCache.setDefault(ResponseCache responseCache)
Java program for implementing java.net.ResponseCache :
Java
import java.io.IOException;import java.net.*;import java.util.HashMap;import java.util.LinkedList;import java.util.List;import java.util.Map;public class JavaResponseCacheExample1 {    public static void main(String args[]) throws Exception    {          // passing the string uri          // Calling the constructor of the URI class        URI uri1 = new URI(uri);          // passing the url          // calling the constructor of the URLConnection        URLConnection urlcon = url.openConnection();        ResponseCache responseCache = new ResponseCache() {            // calling the abstract methods            @Override            public CacheResponse get(                URI uri, String rqstMethod,                Map<String, List<String> > rqstHeaders)                throws IOException            {                return null;            }              @Override            public CacheRequest put(URI uri,                                    URLConnection conn)                throws IOException            {                return null;            }        };          // The sets the system-wide response cache.        ResponseCache.setDefault(responseCache);          // The getDefault() method returns        // the system-wide ResponseCache .        System.out.println("Default value: "                           + ResponseCache.getDefault());        Map<String, List<String> > maps            = new HashMap<String, List<String> >();        List<String> list = new LinkedList<String>();        list.add("REema");          // put() method sets all the applicable cookies,        // present in the response headers into a cookie        // cache        maps.put("1", list);        System.out.println(            "The put() method has been called...");          // The put() method returns the        // CacheRequest for recording        System.out.println(            "The put() method returns: "            + responseCache.put(uri1, urlcon));        System.out.println(            "The get() method has been called...");          // The get() method returns a CacheResponse        // instance if it is available        System.out.println(            "The get() method returns: "            + responseCache.get(uri1, uri, maps));    }} |
Output :
