Android異常： java.lang.IllegalStateException

詳情

這種異常我遇到以下兩種情況：
1. java.lang.IllegalStateException: No wrapped connection.
2.java.lang.IllegalStateException: Adapter is detached.

原因：

1.單線程一次執行一個請求可以正常執行，如果使用多線程，同時執行多個請求時就會出現連接超時.
2.HttpConnection沒有連接池的概念，多少次請求就會建立多少個IO，在訪問量巨大的情況下服務器的IO可能會耗盡。
3.通常是因為HttpClient訪問單一實例的不同的線程或未關閉InputStream的httpresponse。

解決方案：獲得httpclient線程安全

解決前代碼：

public HttpClient httpClient = new DefaultHttpClient();
 public void postNoResult(final Context context, final String url, final Map maps, final String show) {
        new Thread() {
            @Override
            public void run() {
                try {
                    HttpPost post = new HttpPost(url);
                    List params = new ArrayList();
                    for (String key : maps.keySet()) {
                        params.add(new BasicNameValuePair(key, maps.get(key)));
                    }
                    post.setEntity(new UrlEncodedFormEntity(params, HTTP.UTF_8));
                    HttpResponse response = httpClient.execute(post);//報錯位置
                    if (response.getStatusLine().getStatusCode() == 200) {
                        Looper.prepare();
                        String r = EntityUtils.toString(response.getEntity());
                        ToastUtil.print_log(r);
                        if (show != null) {
                            ToastUtil.show(context, show);
                        }
                        Looper.loop();}
                } catch (UnsupportedEncodingException e) {
                    e.printStackTrace();
                } catch (ClientProtocolException e) {
                    e.printStackTrace();
                } catch (IOException e) {
                    e.printStackTrace();
                }}}.start();
    }

解決後代碼：

public HttpClient httpClient = getThreadSafeClient();//獲得httpclient線程安全。
public static DefaultHttpClient getThreadSafeClient() {
//獲得httpclient線程安全的方法
        DefaultHttpClient client = new DefaultHttpClient();
        ClientConnectionManager mgr = client.getConnectionManager();
        HttpParams params = client.getParams();
        client = new DefaultHttpClient(new ThreadSafeClientConnManager(params,
                mgr.getSchemeRegistry()), params);
        return client;
    }

     public void postNoResult(final Context context, final String url, final Map maps, final String show) {
        new Thread() {
            @Override
            public void run() {
                try {
                    HttpPost post = new HttpPost(url);
                    List params = new ArrayList();
                    for (String key : maps.keySet()) {
                        params.add(new BasicNameValuePair(key, maps.get(key)));
                    }
                    post.setEntity(new UrlEncodedFormEntity(params, HTTP.UTF_8));
                    HttpResponse response = httpClient.execute(post);//報錯位置
                    if (response.getStatusLine().getStatusCode() == 200) {
                        Looper.prepare();
                        String r = EntityUtils.toString(response.getEntity());
                        ToastUtil.print_log(r);
                        if (show != null) {
                            ToastUtil.show(context, show);
                        }
                        Looper.loop();}
                } catch (UnsupportedEncodingException e) {
                    e.printStackTrace();
                } catch (ClientProtocolException e) {
                    e.printStackTrace();
                } catch (IOException e) {
                    e.printStackTrace();
                }}}.start();
    }