使用代理访问网络(HttpClient与restTemplate与UrlConnection)

1.搭建一台代理服务器

2.HttpClient方式如下：

•      引入包：

<!-- https://mvnrepository.com/artifact/org.apache.httpcomponents/httpclient -->
<dependency>
    <groupId>org.apache.httpcomponents</groupId>
    <artifactId>httpclient</artifactId>
    <version>4.5.9</version>
</dependency>

<!-- https://mvnrepository.com/artifact/org.apache.httpcomponents/httpcore -->
<dependency>
    <groupId>org.apache.httpcomponents</groupId>
    <artifactId>httpcore</artifactId>
    <version>4.4.11</version>
</dependency>

• main方法如下，可自己封装：

public static void main(String[] args) throws IOException {
    //创建Httpget实例 ，http://2018.ip138.com/ic.asp为该网址返回对应的ip
    //以下为要访问的网址
    HttpGet httpGet = new HttpGet("http://www.baidu.com");

    //代理IP设置，代理 ip查询地址：https://www.xicidaili.com/
    HttpHost httoHost = new HttpHost("代理服务器ip",端口号);
    // 设置认证
    CredentialsProvider provider = new BasicCredentialsProvider();

    provider.setCredentials(new AuthScope(httoHost), new UsernamePasswordCredentials("username", "password"));

    CloseableHttpClient httpClient = HttpClients.custom().setDefaultCredentialsProvider(provider).build();
    RequestConfig requestConfig = RequestConfig.custom()
            .setConnectTimeout(10000)//设置连接超时时间,单位毫秒
            .setSocketTimeout(10000)//设置读取超时时间,单位毫秒
            .setProxy(httoHost)//设置代理
            .build();
    httpGet.setConfig(requestConfig);
    //设置Http报文头信息
    httpGet.setHeader("User-Agent", "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:50.0) Gecko/20100101 Firefox/50.0");

    CloseableHttpResponse response = httpClient.execute(httpGet); // 执行http get请求

    if (response != null){
        HttpEntity entity = response.getEntity();  //获取返回实体
        if (entity != null){
            System.out.println("网页内容为：");
            System.out.println(EntityUtils.toString(entity,"gbk"));
        }
    }
    if (response != null){
        response.close();
    }
    if (httpClient != null){
        httpClient.close();
    }
}

• restTemplate方式设置代理

       

@Bean
RestTemplate createRestTemplate() throws Exception {
    final String username = "xxxx";
    final String password = "xxxx";
    final String proxyUrl = "代理服务器ip或域名";
    final int port = 端口号;

    CredentialsProvider credsProvider = new BasicCredentialsProvider();
    credsProvider.setCredentials(
            new AuthScope(proxyUrl, port),
            new UsernamePasswordCredentials(username, password));

    HttpHost myProxy = new HttpHost(proxyUrl, port);
    HttpClientBuilder clientBuilder = HttpClientBuilder.create();

    clientBuilder.setProxy(myProxy).setDefaultCredentialsProvider(credsProvider).disableCookieManagement();

    HttpClient httpClient = clientBuilder.build();
    HttpComponentsClientHttpRequestFactory factory = new HttpComponentsClientHttpRequestFactory();
    factory.setHttpClient(httpClient);

    return new RestTemplate(factory);
}

• URLConnection方式使用代理网络访问

public static void main(String[] args) throws IOException {
    // 设置代理服务器
    InetSocketAddress addr = new InetSocketAddress("代理服务器ip",8080);
    Proxy proxy = new Proxy(Proxy.Type.HTTP, addr); // http 代理
    //配置帐号密码信息
    Authenticator authenticator = new Authenticator() {
        @Override
        protected PasswordAuthentication getPasswordAuthentication() {
            return new PasswordAuthentication("userName","password".toCharArray());
        }
    };
    Authenticator.setDefault(authenticator);
    URLConnection connection = new URL("http://www.baidu.com").openConnection(proxy);
    InputStream inputStream = connection.getInputStream();
    ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
    int i;
    while ((i = inputStream.read()) != -1){
        byteArrayOutputStream.write(i);
    }
    String s = byteArrayOutputStream.toString();
    System.out.println("...");
}

PS:本文参考了其他多篇文章进行的总结，已经过测试，肯定能跑通，如果你的代理服务器搭建好了的话，写篇博客，怕忘了