如何在 Java 中获取 URL 的 HTTP 响应代码？

Question

请告诉我获取特定 URL 的响应代码的步骤或代码。

Answer 1

HttpURLConnection：

URL url = new URL("http://example.com");
HttpURLConnection connection = (HttpURLConnection)url.openConnection();
connection.setRequestMethod("GET");
connection.connect();

int code = connection.getResponseCode();

这这绝不是一个强有力的例子；你需要处理 IOException 之类的。但它应该让你开始。

如果您需要更多功能，请查看 HttpClient。

Answer 2

URL url = new URL("http://www.google.com/humans.txt");
HttpURLConnection http = (HttpURLConnection)url.openConnection();
int statusCode = http.getResponseCode();

Answer 3

您可以尝试以下操作：

class ResponseCodeCheck 
{

    public static void main (String args[]) throws Exception
    {

        URL url = new URL("http://google.com");
        HttpURLConnection connection = (HttpURLConnection)url.openConnection();
        connection.setRequestMethod("GET");
        connection.connect();

        int code = connection.getResponseCode();
        System.out.println("Response code of the object is "+code);
        if (code==200)
        {
            System.out.println("OK");
        }
    }
}

Answer 4

import java.io.IOException;
import java.net.URL;
import java.net.HttpURLConnection;

public class API{
    public static void main(String args[]) throws IOException
    {
        URL url = new URL("http://www.google.com");
        HttpURLConnection http = (HttpURLConnection)url.openConnection();
        int statusCode = http.getResponseCode();
        System.out.println(statusCode);
    }
}

Answer 5

这对我有用：

import java.io.IOException;
import java.net.HttpURLConnection;
import java.net.URL;

public class UrlHelpers {

    public static int getHTTPResponseStatusCode(String u) throws IOException {

        URL url = new URL(u);
        HttpURLConnection http = (HttpURLConnection)url.openConnection();
        return http.getResponseCode();
    }
}

希望这对某人有帮助:)

Answer 6

这对我有用：

            import org.apache.http.client.HttpClient;
            import org.apache.http.client.methods.HttpGet;  
            import org.apache.http.impl.client.DefaultHttpClient;
            import org.apache.http.HttpResponse;
            import java.io.BufferedReader;
            import java.io.InputStreamReader;



            public static void main(String[] args) throws Exception {   
                        HttpClient client = new DefaultHttpClient();
                        //args[0] ="http://hostname:port/xyz/zbc";
                        HttpGet request1 = new HttpGet(args[0]);
                        HttpResponse response1 = client.execute(request1);
                        int code = response1.getStatusLine().getStatusCode();

                         try(BufferedReader br = new BufferedReader(new InputStreamReader((response1.getEntity().getContent())));){
                            // Read in all of the post results into a String.
                            String output = "";
                            Boolean keepGoing = true;
                            while (keepGoing) {
                                String currentLine = br.readLine();          
                                if (currentLine == null) {
                                    keepGoing = false;
                                } else {
                                    output += currentLine;
                                }
                            }
                            System.out.println("Response-->"+output);   
                         }

                         catch(Exception e){
                              System.out.println("Exception"+e);  

                          }


                   }

Answer 7

通过扫描仪获取数据（负载不均匀）的有效方法。

public static String getResponseFromHttpUrl(URL url) throws IOException {
    HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
    try {
        InputStream in = urlConnection.getInputStream();

        Scanner scanner = new Scanner(in);
        scanner.useDelimiter("\\A");  // Put entire content to next token string, Converts utf8 to 16, Handles buffering for different width packets

        boolean hasInput = scanner.hasNext();
        if (hasInput) {
            return scanner.next();
        } else {
            return null;
        }
    } finally {
        urlConnection.disconnect();
    }
}

Answer 8

尝试这段检查 400 错误消息的代码

huc = (HttpURLConnection)(new URL(url).openConnection());

huc.setRequestMethod("HEAD");

huc.connect();

respCode = huc.getResponseCode();

if(respCode >= 400) {
    System.out.println(url+" is a broken link");
} else {
    System.out.println(url+" is a valid link");
}

Answer 9

这是完整的静态方法，您可以修改它来设置 IOException 发生时的等待时间和错误代码：

  public static int getResponseCode(String address) {
    return getResponseCode(address, 404);
  }

  public static int getResponseCode(String address, int defaultValue) {
    try {
      //Logger.getLogger(WebOperations.class.getName()).info("Fetching response code at " + address);
      URL url = new URL(address);
      HttpURLConnection connection = (HttpURLConnection) url.openConnection();
      connection.setConnectTimeout(1000 * 5); //wait 5 seconds the most
      connection.setReadTimeout(1000 * 5);
      connection.setRequestProperty("User-Agent", "Your Robot Name");
      int responseCode = connection.getResponseCode();
      connection.disconnect();
      return responseCode;
    } catch (IOException ex) {
      Logger.getLogger(WebOperations.class.getName()).log(Level.INFO, "Exception at {0} {1}", new Object[]{address, ex.toString()});
      return defaultValue;
    }
  }

Answer 10

HttpURLConnection connection = (HttpURLConnection) url.openConnection();
            connection.setDoOutput(true);
            connection.setDoInput(true);
            connection.setRequestMethod("POST");

。
。
。
。
。
。
。

System.out.println("Value" + connection.getResponseCode());
             System.out.println(connection.getResponseMessage());
             System.out.println("content"+connection.getContent());

Answer 11

这是一个老问题，但让我们以 REST 方式（JAX-RS）来展示：

import java.util.Arrays;
import javax.ws.rs.*

(...)

Response response = client
    .target( url )
    .request()
    .get();

// Looking if response is "200", "201" or "202", for example:
if( Arrays.asList( Status.OK, Status.CREATED, Status.ACCEPTED ).contains( response.getStatusInfo() ) ) {
    // lets something...
}

(...)

Answer 12

您可以使用java http/https url 连接从网站获取响应代码和其他信息，这里是一个示例代码。

 try {

            url = new URL("https://www.google.com"); // create url object for the given string  
            HttpURLConnection connection = (HttpURLConnection) url.openConnection();
            if(https_url.startsWith("https")){
                 connection = (HttpsURLConnection) url.openConnection();
            }

            ((HttpURLConnection) connection).setRequestMethod("HEAD");
            connection.setConnectTimeout(50000); //set the timeout
            connection.connect(); //connect
            String responseMessage = connection.getResponseMessage(); //here you get the response message
             responseCode = connection.getResponseCode(); //this is http response code
            System.out.println(obj.getUrl()+" is up. Response Code : " + responseMessage);
            connection.disconnect();`
}catch(Exception e){
e.printStackTrace();
}