#httpasyncclient 引起的内存泄漏问题

 List<HttpUriRequest> cache = new ArrayList<HttpUriRequest>(n);
        for (int i = 0; i < n; i++) {
            HttpGet request = new HttpGet("http://www.baidu.com?a="+i);
            cache.add(request);
        }


 HttpAsyncClient httpClient = new HttpAsyncClient();
        int i = 0;

        while (true){

            final HttpUriRequest request = cache.get(i%cache.size());
            httpClient.execute(request, new FutureCallback<HttpResponse>() {
                public void completed(final HttpResponse response) {
                    System.out.println(request.getRequestLine() + "->" + response.getStatusLine());
                }

                public void failed(final Exception ex) {
                    System.out.println(request.getRequestLine() + "->" + ex);
                }

                public void cancelled() {
                    System.out.println(request.getRequestLine() + " cancelled");
                }

            });
            i++;
            Thread.sleep(100);
        }

FutureCallback 类会被不断的创建，而在内部这个callback 是连接到httpget上，而httpget是个list cache 没释放。大量的回调类晋升到了old区，最终导致 Full GC 产生。

https://zhuanlan.zhihu.com/p/212778161