How to pass parameters to load method in addition to KEY

[saiye...@gmail.com]

I have written a program to cache objects using Google Guava. My problem is how to pass additional parameters to Guava Load method. Here is the code. Below you see in this line - I have made fileId and pageno as key - cache.get(fileID+pageNo);. Now when cache.get is called and when that key is not in the cache - guava will call the load method of class PreviewCacheLoader which I have given below as well.

public class PreviewCache {
    static final LoadingCache<String, CoreObject> cache = CacheBuilder.newBuilder()
          .maximumSize(1000)
          .expireAfterWrite(5, TimeUnit.MINUTES) 
          .build(new PreviewCacheLoader());

   public CoreObject getPreview(String strTempPath, int pageNo, int requiredHeight, String fileID, String strFileExt,  String ssoId) throws IOException 
    {
        CoreObject coreObject = null;
        try {
            coreObject = cache.get(fileID+pageNo, HOW TO PASS pageNO and requiredHeight because I want to keep key as ONLY fileID+pageNo );
        } catch (ExecutionException e) {
            e.printStackTrace();
        }
        return coreObject;
    }
}

How to pass parameters from above which are int and String to below Load method in addition to key parameter

public class PreviewCacheLoader extends CacheLoader<String, CoreObject> {

@Override
public CoreObject load(String fileIDpageNo, HOW TO GET pageNO and requiredHeight) throws Exception {

    CoreObject coreObject = new CoreObject();
    // MAKE USE OF PARAMETERS pageNO and requiredHeight
    // Populate coreObject here 
    return coreObject;


}

[Louis Wasserman]

You cannot do it like that, but one possible alternative is for you to use Cache.get(K, Callable<V>), and to construct the Callable with all the extra information that would be necessary.

Louis Wasserman
wasserm...@gmail.com
http://profiles.google.com/wasserman.louis

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[saiye...@gmail.com]

Thank You Louis - So in that case do I need these two things. 1.  .build(new PreviewCacheLoader()); 2. And entire PreviewCacheLoader class. What I understood is I need to move the logic of load method in  PreviewCacheLoader class to the callable call method. Is that correct ? 

[saiye...@gmail.com]

So your suggestion worked but I still don't understand. Really appreciate if you clear my concepts. So do I still need . 1.  line ----.build(new PreviewCacheLoader()); 2. And entire PreviewCacheLoader class. We don't need to call PreviewCacheLoader now as we don't need load method because call method is doing it. Please clear.