Package org.apache.jmeter.protocol.http.sampler

Class ResourcesDownloader

java.lang.Object

org.apache.jmeter.protocol.http.sampler.ResourcesDownloader

public class ResourcesDownloader
extends Object

Manages the parallel http resources download.
A shared thread pool is used by all the sample.
A sampler will usually do the following

 
   // list of AsynSamplerResultHolder to download
   List<Callable<AsynSamplerResultHolder>> list = ...

   // max parallel downloads
   int maxConcurrentDownloads = ...

   // get the singleton instance
   ResourcesDownloader resourcesDownloader = ResourcesDownloader.getInstance();

   // schedule the downloads and wait for the completion
   List<Future<AsynSamplerResultHolder>> retExec =
           resourcesDownloader.invokeAllAndAwaitTermination(maxConcurrentDownloads, list);

 

the call to invokeAllAndAwaitTermination will block until the downloads complete or get interrupted
the Future list only contains task that have been scheduled in the threadpool.
The status of those futures are either done or cancelled

Future enhancements:

• this implementation should be replaced with a NIO async download in order to reduce the number of threads needed

Since:

3.0

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	ResourcesDownloader.AsynSamplerResultHolder	Holder of AsynSampler result

Method Summary

Modifier and Type	Method	Description
static ResourcesDownloader	getInstance()
List<Future<ResourcesDownloader.AsynSamplerResultHolder>>	invokeAllAndAwaitTermination(int maxConcurrentDownloads, List<Callable<ResourcesDownloader.AsynSamplerResultHolder>> list)	This method will block until the downloads complete or it get interrupted the Future list returned by this method only contains tasks that have been scheduled in the threadpool. The status of those futures are either done or cancelled
void	shrink()	this method will try to shrink the thread pool size as much as possible it should be called at the end of a test

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

getInstance

public static ResourcesDownloader getInstance()

shrink

public void shrink()

this method will try to shrink the thread pool size as much as possible it should be called at the end of a test

invokeAllAndAwaitTermination

public List<Future<ResourcesDownloader.AsynSamplerResultHolder>> invokeAllAndAwaitTermination(int maxConcurrentDownloads,
 List<Callable<ResourcesDownloader.AsynSamplerResultHolder>> list)
                                                                                       throws InterruptedException

This method will block until the downloads complete or it get interrupted the Future list returned by this method only contains tasks that have been scheduled in the threadpool.
The status of those futures are either done or cancelled

Parameters:

maxConcurrentDownloads - max concurrent downloads

list - list of resources to download

Returns:

list tasks that have been scheduled

Throws:

InterruptedException - when interrupted while waiting