apache.commons.httpclient怎样拦截或过滤Http请求，记录URL、入参、出参等信息

在使用apache.commons.httpclient发送HTTP请求时，可以通过实现自定义的拦截器（Interceptor）来拦截或过滤请求，并记录URL、入参、出参等信息。具体步骤如下：

1. 创建自定义的拦截器类，实现HttpClient的Interceptor接口，覆盖intercept方法。

public class MyInterceptor implements Interceptor {
    @Override
    public void intercept(HttpRequest request, byte[] body, 
                          org.apache.http.protocol.HttpContext context) 
                          throws HttpException, IOException {
        // 记录请求信息
        System.out.println("Request URL: " + request.getRequestLine().getUri());
        System.out.println("Request Body: " + new String(body, "UTF-8"));

        // 执行请求
        HttpResponse response = Proxies.getDefault().execute(request, context);

        // 记录响应信息
        System.out.println("Response Status: " + response.getStatusLine().getStatusCode());
        System.out.println("Response Body: " + EntityUtils.toString(response.getEntity()));
    }
}

2. 使用自定义的拦截器类进行HTTP请求。

HttpClient httpClient = new HttpClient();
httpClient.getHostConfiguration().setHost("www.example.com");
httpClient.getState().setCredentials(new AuthScope("www.example.com", 80), 
                                      new UsernamePasswordCredentials("username", "password"));

// 创建自定义的拦截器
MyInterceptor interceptor = new MyInterceptor();

// 将拦截器添加到HttpClient中
httpClient.getParams().setParameter(InterceptorList.PROTOCOL_INTERCEPTOR_LIST, 
                                      Collections.singletonList(interceptor));

// 创建HTTP请求
GetMethod getMethod = new GetMethod("/test");
int statusCode = httpClient.executeMethod(getMethod);

这样，当使用HttpClient发送HTTP请求时，就会自动执行自定义的拦截器，记录请求信息、响应信息等。