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如何在Java中对HttpClient请求设置代理主机

apache-commons-httpclient http java

Developer · 技术社区 · 9 年前

我想在发送前设置代理 HttpClient

Curl命令:

**curl -I -x IP:80  URL**

java文件中的代码更改:

HttpClient client = new HttpClient();
System.getProperties().put("http.proxyHost", "someProxyURL");
System.getProperties().put("http.proxyPort", "someProxyPort");
EntityEnclosingMethod method = new PostMethod(url);
method.setRequestEntity(new StringRequestEntity(requestXML, "text/xml", "utf-8"));

java.net.ConnectException: Connection refused (Connection refused)

这表明我无法将该URL与我试图用于连接URL的代理连接起来。

4 回复 | 直到 6 年前

SkyWalker 9 年前

本教程提供了一个完整的示例: How do I setting a proxy for HttpClient?

package org.kodejava.example.commons.httpclient;

import org.apache.commons.httpclient.Credentials;
import org.apache.commons.httpclient.HostConfiguration;
import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.HttpMethod;
import org.apache.commons.httpclient.HttpStatus;
import org.apache.commons.httpclient.UsernamePasswordCredentials;
import org.apache.commons.httpclient.auth.AuthScope;
import org.apache.commons.httpclient.methods.GetMethod;

import java.io.IOException;

public class HttpGetProxy {
    private static final String PROXY_HOST = "proxy.host.com";
    private static final int PROXY_PORT = 8080;

    public static void main(String[] args) {
        HttpClient client = new HttpClient();
        HttpMethod method = new GetMethod("https://kodejava.org");

        HostConfiguration config = client.getHostConfiguration();
        config.setProxy(PROXY_HOST, PROXY_PORT);

        String username = "guest";
        String password = "s3cr3t";
        Credentials credentials = new UsernamePasswordCredentials(username, password);
        AuthScope authScope = new AuthScope(PROXY_HOST, PROXY_PORT);

        client.getState().setProxyCredentials(authScope, credentials);

        try {
            client.executeMethod(method);

            if (method.getStatusCode() == HttpStatus.SC_OK) {
                String response = method.getResponseBodyAsString();
                System.out.println("Response = " + response);
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            method.releaseConnection();
        }
    }
}

需要添加jar文件 : http://repo1.maven.org/maven2/commons-httpclient/commons-httpclient/3.1/commons-httpclient-3.1.jar

HttpHost proxy = new HttpHost("ip address",port number);
DefaultHttpClient httpclient = new DefaultHttpClient();
httpclient.getParams().setParameter(ConnRoutePNames.DEFAULT_PROXY,proxy);

HttpPost httpost = new HttpPost(url);
List<NameValuePair> nvps = new ArrayList<NameValuePair>();
nvps.add(new BasicNameValuePair("param name", param));
httpost.setEntity(new UrlEncodedFormEntity(nvps, HTTP.ISO_8859_1));
HttpResponse response = httpclient.execute(httpost);

HttpEntity entity = response.getEntity();
System.out.println("Request Handled?: " + response.getStatusLine());
InputStream in = entity.getContent();
httpclient.getConnectionManager().shutdown();

https://stackoverflow.com/a/4957144

对于其他版本,如4.3或4.3以上,您可以通过以下步骤回答: Apache HttpClient 4.1 - Proxy Authentication

DontPanic 9 年前

我认为这可能会有所帮助:

HttpClient client = new HttpClient();

HostConfiguration config = client.getHostConfiguration();
config.setProxy("someProxyURL", "someProxyPort");

Credentials credentials = new UsernamePasswordCredentials("username", "password");
AuthScope authScope = new AuthScope("someProxyURL", "someProxyPort");
client.getState().setProxyCredentials(authScope, credentials);

EntityEnclosingMethod method = new PostMethod(url);
method.setRequestEntity(new StringRequestEntity(requestXML, "text/xml", "utf-8"));

Eugene Lebedev 9 年前

添加maven依赖项(4.2.X+):

<dependency>
    <groupId>org.apache.httpcomponents</groupId>
    <artifactId>httpclient</artifactId>
    <version>4.5.3</version>
    <exclusions>
        <exclusion>
            <artifactId>commons-logging</artifactId>
            <groupId>commons-logging</groupId>
        </exclusion>
    </exclusions>
</dependency>

使用 HttpClientBuilder 并设置标志 useSystemProperties :

HttpClient client = HttpClientBuilder.create().useSystemProperties().build();

那么你至少有两个选择:

java -Djava.net.useSystemProxies=true 
     -Dhttp.proxyHost=PROXY_HOST
     -Dhttp.proxyPort=PROXY_PORT 
     -Dhttp.proxyUser=USERNAME
     -Dhttp.proxyPassword=PASSWORD
     -jar your-app.jar

${JAVA_HOME}/lib/net.properties ):

java.net.useSystemProxies=true
http.proxyHost=some-host
http.proxyPort=some-port

Frischling 9 年前

系统属性通常必须预先设置好,这意味着在jvm启动时 -Dhttp.proxyHost=some.host.com -Dhttp.proxyPort=8080 ,不要忘记httpsProxyHost和…端口)

我个人觉得Jersey客户端实现更容易使用,如果您可以选择切换的话。