ConnectTimeoutException:
當連接HTTP服務器或者等待HttpConnectionManager管理的一個有效連接超時引發該異常。
SocketTimeoutException:
當讀取或者接收Socket超時引起該異常。
在Apache的HttpClient包中,有三個設置超時的地方:
/* 從連接池中取連接的超時時間*/
ConnManagerParams.setTimeout(params, 1000);
/*連接超時*/
HttpConnectionParams.setConnectionTimeout(params, 2000);
/*請求超時*/
HttpConnectionParams.setSoTimeout(params, 4000);
第一行設置ConnectionPoolTimeout:
這定義了從ConnectionManager管理的連接池中取出連接的超時時間,此處設置為1秒。
第二行設置ConnectionTimeout:
這定義了通過網絡與服務器建立連接的超時時間。Httpclient包中通過一個異步線程去創建與服務器的socket連接,這就是該socket連接的超時時間,此處設置為2秒。
第三行設置SocketTimeout:
這定義了Socket讀數據的超時時間,即從服務器獲取響應數據需要等待的時間,此處設置為4秒。
以上3種超時分別會拋出ConnectionPoolTimeoutException,ConnectionTimeoutException與SocketTimeoutException。
例
測試版本為HttpClient——3.1
一:連接超時:connectionTimeout
1:指的是連接一個url的連接等待時間。
2:設置方法為:
代碼如下 復制代碼public class TestHttpClientMain {
public static void main(String[] args) {
HttpClient client = new HttpClient();
HttpMethod method = new GetMethod(
"http://test.com");
client.getHttpConnectionManager().getParams()
.setConnectionTimeout(3000);
client.getHttpConnectionManager().getParams().setSoTimeout(3000);
try {
int statusCode = client.executeMethod(method);
System.out.println(statusCode);
byte[] responseBody = null;
responseBody = method.getResponseBody();
String result = new String(responseBody);
System.out.println(result);
} catch (HttpException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
3:測試的時候,將url改為一個不存在的url:“http://www.111cn.net"
4:超時時間3000ms過後,系統報出異常。
代碼如下 復制代碼org.apache.commons.httpclient.ConnectTimeoutException: The host did not accept the connection within timeout of 3000 ms
at org.apache.commons.httpclient.protocol.ReflectionSocketFactory.createSocket(ReflectionSocketFactory.java:155)
at org.apache.commons.httpclient.protocol.DefaultProtocolSocketFactory.createSocket(DefaultProtocolSocketFactory.java:125)
at org.apache.commons.httpclient.HttpConnection.open(HttpConnection.java:707)
at org.apache.commons.httpclient.HttpMethodDirector.executeWithRetry(HttpMethodDirector.java:387)
at org.apache.commons.httpclient.HttpMethodDirector.executeMethod(HttpMethodDirector.java:171)
at org.apache.commons.httpclient.HttpClient.executeMethod(HttpClient.java:397)
二:讀取數據超時:soTimeout
1:指的是連接上一個url,獲取response的返回等待時間
2:設置方法
代碼如下 復制代碼public class TestHttpClientMain {
public static void main(String[] args) {
HttpClient client = new HttpClient();
HttpMethod method = new GetMethod(
"http://localhost:8080/firstTest.htm?method=test");
client.getHttpConnectionManager().getParams()
.setConnectionTimeout(3000);
client.getHttpConnectionManager().getParams().setSoTimeout(2000);
try {
int statusCode = client.executeMethod(method);
System.out.println(statusCode);
byte[] responseBody = null;
responseBody = method.getResponseBody();
String result = new String(responseBody);
System.out.println(result);
} catch (HttpException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
3:測試的時候的連接url為我本地開啟的一個url,http://localhost:8080/firstTest.htm?method=test
在我這個測試url裡,當訪問到這個鏈接時,線程sleep一段時間,來模擬返回response超時。
代碼如下 復制代碼@RequestMapping(params = "method=test") //<——②
public String testMethod(ModelMap model) {
try {
Thread.sleep(3000);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
System.out.println("call testMethod method.");
model.addAttribute("name", "test method");
return "test";
}
4:將讀取response返回超時時間設的時間比那個sleep時間短之後,運行程序給出異常:
代碼如下 復制代碼java.net.SocketTimeoutException: Read timed out
at java.net.SocketInputStream.socketRead0(Native Method)
at java.net.SocketInputStream.read(Unknown Source)
at java.io.BufferedInputStream.fill(Unknown Source)
at java.io.BufferedInputStream.read(Unknown Source)
at org.apache.commons.httpclient.HttpParser.readRawLine(HttpParser.java:78)
at org.apache.commons.httpclient.HttpParser.readLine(HttpParser.java:106)
at org.apache.commons.httpclient.HttpConnection.readLine(HttpConnection.java:1116)
at org.apache.commons.httpclient.HttpMethodBase.readStatusLine(HttpMethodBase.java:1973)
at org.apache.commons.httpclient.HttpMethodBase.readResponse(HttpMethodBase.java:1735)