Java 从url获取http响应代码

我想写一个Java程序，它将点击一个URL并打印状态码（即200、404等）。我使用的是

HttpUrlConnection

api，但它只显示异常，不打印状态代码

URL url = new URL("https://abc.com/test.html");
HttpURLConnection connection = (HttpURLConnection)url.openConnection();
connection.setRequestMethod("GET");
connection.connect();

int code = connection.getResponseCode();  
System.out.println("code: "+code);

---

只有当您能够访问

URL

时，才会从该URL获得响应代码。在您的代码中，您似乎正在使用一个不存在的URL，因此必须获得无法访问的主机异常

尝试访问有效的URL并检查响应代码：

URL url = new URL("https://google.com");

---

只有当您能够访问

URL

时，才会从该URL获得响应代码。在您的代码中，您似乎正在使用一个不存在的URL，因此必须获得无法访问的主机异常

尝试访问有效的URL并检查响应代码：

URL url = new URL("https://google.com");

---

我按以下方式尝试了your代码，它对我很有效：

import java.net.*;

public class Action 
{

    public static void main(String[] args)
    {
        try
        {
            URL url = new URL("http://localhost:8888");
            HttpURLConnection connection = (HttpURLConnection)url.openConnection();
            connection.setRequestMethod("GET");
            connection.connect();

            int code = connection.getResponseCode();  
            System.out.println("code: "+code);
        }
        catch(Exception e)
        {

        }

    }
}

---

还有谷歌。

我尝试了以下your代码，对我来说效果很好：

import java.net.*;

public class Action 
{

    public static void main(String[] args)
    {
        try
        {
            URL url = new URL("http://localhost:8888");
            HttpURLConnection connection = (HttpURLConnection)url.openConnection();
            connection.setRequestMethod("GET");
            connection.connect();

            int code = connection.getResponseCode();  
            System.out.println("code: "+code);
        }
        catch(Exception e)
        {

        }

    }
}

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

int code = connection.getResponseCode();  
System.out.println("code: "+code);

还有谷歌

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

int code = connection.getResponseCode();  
System.out.println("code: "+code);

请尝试使用其他url，因为您使用的url无效。“”不存在这样的页面，所以它给出了异常。尝试一个有效的url，它会很好地工作

---

请尝试使用其他url，因为您使用的url无效。“”不存在这样的页面，所以它给出了异常。尝试一个有效的url，它会正常工作。

即使我遇到了相同的异常，即java.net.ConnectException：连接超时：如果我没有在代码中添加代理和端口，则连接

java.net.ConnectException: Connection timed out: connect
    at java.net.PlainSocketImpl.socketConnect(Native Method)
    at java.net.PlainSocketImpl.doConnect(Unknown Source)
    at java.net.PlainSocketImpl.connectToAddress(Unknown Source)
    at java.net.PlainSocketImpl.connect(Unknown Source)
    at java.net.SocksSocketImpl.connect(Unknown Source)
    at java.net.Socket.connect(Unknown Source)
    at com.sun.net.ssl.internal.ssl.SSLSocketImpl.connect(Unknown Source)
    at com.sun.net.ssl.internal.ssl.BaseSSLSocketImpl.connect(Unknown Source)
    at sun.net.NetworkClient.doConnect(Unknown Source)
    at sun.net.www.http.HttpClient.openServer(Unknown Source)
    at sun.net.www.http.HttpClient.openServer(Unknown Source)
    at sun.net.www.protocol.https.HttpsClient.<init>(Unknown Source)
    at sun.net.www.protocol.https.HttpsClient.New(Unknown Source)
    at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.getNewHttpClient(Unknown Source)
    at sun.net.www.protocol.http.HttpURLConnection.plainConnect(Unknown Source)
    at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(Unknown Source)
    at sun.net.www.protocol.https.HttpsURLConnectionImpl.connect(Unknown Source)
    at edu.sandip.TestURLConnection.main(TestURLConnection.java:23)

注: 1.您需要从组织网络管理员处获取proxyHost IP。

---

2.您应该使用HttpsURLConnection来访问https URL。

即使我遇到了相同的异常，例如java.net.ConnectException:Connection timed out:connect如果我没有在您的代码中添加代理和端口

java.net.ConnectException: Connection timed out: connect
    at java.net.PlainSocketImpl.socketConnect(Native Method)
    at java.net.PlainSocketImpl.doConnect(Unknown Source)
    at java.net.PlainSocketImpl.connectToAddress(Unknown Source)
    at java.net.PlainSocketImpl.connect(Unknown Source)
    at java.net.SocksSocketImpl.connect(Unknown Source)
    at java.net.Socket.connect(Unknown Source)
    at com.sun.net.ssl.internal.ssl.SSLSocketImpl.connect(Unknown Source)
    at com.sun.net.ssl.internal.ssl.BaseSSLSocketImpl.connect(Unknown Source)
    at sun.net.NetworkClient.doConnect(Unknown Source)
    at sun.net.www.http.HttpClient.openServer(Unknown Source)
    at sun.net.www.http.HttpClient.openServer(Unknown Source)
    at sun.net.www.protocol.https.HttpsClient.<init>(Unknown Source)
    at sun.net.www.protocol.https.HttpsClient.New(Unknown Source)
    at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.getNewHttpClient(Unknown Source)
    at sun.net.www.protocol.http.HttpURLConnection.plainConnect(Unknown Source)
    at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(Unknown Source)
    at sun.net.www.protocol.https.HttpsURLConnectionImpl.connect(Unknown Source)
    at edu.sandip.TestURLConnection.main(TestURLConnection.java:23)

注: 1.您需要从组织网络管理员处获取proxyHost IP。

---

2.您应该使用HttpsURLConnection访问https URL。

但它只显示异常该异常是什么？连接超时。连接超时不是HTTP响应代码。根本没有响应。如何使用

HttpURLConnection#setReadTimeout

！并且也要做正确的异常处理…尝试设置

connection.setConnectTimeout（8000）像这样？但它只显示异常该异常是什么？连接超时。连接超时不是HTTP响应代码。根本没有响应。如何使用
HttpURLConnection#setReadTimeout
！并进行适当的异常处理…尝试设置
connection.setConnectTimeout（8000）