1.pom引用
<dependency>
<groupId>commons-httpclient</groupId>
<artifactId>commons-httpclient</artifactId>
<version>3.1</version>
</dependency>
2.java代碼
import java.io.IOException;
import org.apache.commons.httpclient.DefaultHttpMethodRetryHandler;
import org.apache.commons.httpclient.Header;
import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.HttpException;
import org.apache.commons.httpclient.HttpStatus;
import org.apache.commons.httpclient.methods.GetMethod;
import org.apache.commons.httpclient.params.HttpMethodParams;
public class HttpClientUtil {
/**
* httpClient的get請求方式
* 使用GetMethod來訪問一個URL對應的網頁實現步驟:
* 1.生成一個HttpClient對象並設置相應的參數;
* 2.生成一個GetMethod對象並設置響應的參數;
* 3.用HttpClient生成的對象來執行GetMethod生成的Get方法;
* 4.處理響應狀態碼;
* 5.若響應正常,處理HTTP響應內容;
* 6.釋放連接。
* @param url
* @param charset
* @return
*/
public static String doGet(String url, String charset){
/**
* 1.生成HttpClient對象並設置參數
*/
HttpClient httpClient = new HttpClient();
//設置Http連接超時爲5秒
httpClient.getHttpConnectionManager().getParams().setConnectionTimeout(5000);
/**
* 2.生成GetMethod對象並設置參數
*/
GetMethod getMethod = new GetMethod(url);
//設置get請求超時爲5秒
getMethod.getParams().setParameter(HttpMethodParams.SO_TIMEOUT, 5000);
//設置請求重試處理,用的是默認的重試處理:請求三次
getMethod.getParams().setParameter(HttpMethodParams.RETRY_HANDLER, new DefaultHttpMethodRetryHandler());
String response = "";
/**
* 3.執行HTTP GET 請求
*/
try {
int statusCode = httpClient.executeMethod(getMethod);
/**
* 4.判斷訪問的狀態碼
*/
if (statusCode != HttpStatus.SC_OK){
System.err.println("請求出錯:" + getMethod.getStatusLine());
}
/**
* 5.處理HTTP響應內容
*/
//HTTP響應頭部信息,這裏簡單打印
Header[] headers = getMethod.getResponseHeaders();
for (Header h: headers){
System.out.println(h.getName() + "---------------" + h.getValue());
}
//讀取HTTP響應內容,這裏簡單打印網頁內容
//讀取爲字節數組
byte[] responseBody = getMethod.getResponseBody();
response = new String(responseBody, charset);
System.out.println("-----------response:" + response);
//讀取爲InputStream,在網頁內容數據量大時候推薦使用
//InputStream response = getMethod.getResponseBodyAsStream();
} catch (HttpException e) {
//發生致命的異常,可能是協議不對或者返回的內容有問題
System.out.println("請檢查輸入的URL!");
e.printStackTrace();
} catch (IOException e){
//發生網絡異常
System.out.println("發生網絡異常!");
}finally {
/**
* 6.釋放連接
*/
getMethod.releaseConnection();
}
return response;
}
public static void main(String[] args) {
doGet("http://apidata.com/CallAPI/BaiduPages?key=8d893a8&domainName=zuma.com", "UTF-8");
}
}