HTTP Illegal state exception <p>I have the following code, which in general works without problems:</p> <pre><code>HttpPost post = new HttpPost(sendURL); StringEntity se = new StringEntity( postJSON.toString(), "UTF-8"); se.setContentType(new BasicHeader(HTTP.CONTENT_TYPE, "application/json")); post.setEntity(se); response = httpClient.execute(post); </code></pre> <p>When postJSON has the following, I get an IllegalStateException, with the message "Manager is shut down":</p> <pre><code>{"action":"add","items":["61515"],"screen":"display","customer_number":"200001013"} </code></pre> <p>I got a similar message when the items array had malformed content, but I don't see the problem here. Also, the response is immediate, so I am pretty sure that the HTTP library is throwing the exception, not the server. What is wrong with this JSON object?</p> <p>Furthermore, testing the JSON at <a href="http://jsonlint.com/" rel="nofollow">JSONLint</a> shows me that the JSON parses correctly, including the array with "61515", which is the new element in the code.</p>