1. jar包的变更，可以在此下载最新的jar包：http://hc.apache.org/downloads.cgi
2. 把org.apache.commons.httpclient.*修改到import org.apache.http.*。具体变更哪些，就要看利用了HttpClient的哪些功能
   比如：
   Java代码  

   1. import org.apache.commons.httpclient.HttpClient;
   2. import org.apache.commons.httpclient.HttpStatus;
   3. import org.apache.commons.httpclient.HttpException;
   4. import org.apache.commons.httpclient.methods.GetMethod;
   5. import org.apache.commons.httpclient.ConnectTimeoutException;

   import org.apache.commons.httpclient.HttpClient;
   import org.apache.commons.httpclient.HttpStatus;
   import org.apache.commons.httpclient.HttpException;
   import org.apache.commons.httpclient.methods.GetMethod;
   import org.apache.commons.httpclient.ConnectTimeoutException;

   To

   Java代码  

   1. import org.apache.http.client.HttpClient;
   2. import org.apache.http.HttpStatus;
   3. import org.apache.http.HttpException;
   4. import org.apache.http.client.methods.HttpGet;
   5. import org.apache.http.conn.ConnectTimeoutException;
   6. import org.apache.http.HttpResponse;
   7. import org.apache.http.impl.client.DefaultHttpClient;

   import org.apache.http.client.HttpClient;
   import org.apache.http.HttpStatus;
   import org.apache.http.HttpException;
   import org.apache.http.client.methods.HttpGet;
   import org.apache.http.conn.ConnectTimeoutException;
   import org.apache.http.HttpResponse;
   import org.apache.http.impl.client.DefaultHttpClient;

3. 使用的各个HttpClient的功能的代码修改。这部分的整理，在使用过程中慢慢补全。本次先介绍Get方法的修改。

Java代码  

1. GetMethod method = new GetMethod(url);
2. int statusCode = client.executeMethod(method);
3. if (statusCode == HttpStatus.SC_OK) {
4. InputStream is = method.getResponseBodyAsStream();
5. // do something with the input stream
6. }
7. method.releaseConnection();

GetMethod method = new GetMethod(url);
int statusCode = client.executeMethod(method);
if (statusCode == HttpStatus.SC_OK) {InputStream is = method.getResponseBodyAsStream();// do something with the input stream
}
method.releaseConnection();

Java代码  

1. HttpGet method = new HttpGet(url);
2. HttpResponse httpResponse = client.execute(method);
3. int statusCode = httpResponse.getStatusLine().getStatusCode();
4. if (statusCode == HttpStatus.SC_OK) {
5. InputStream is = httpResponse.getEntity().getContent();
6. // do something with the input stream
7. }

HttpGet method = new HttpGet(url);
HttpResponse httpResponse = client.execute(method);
int statusCode = httpResponse.getStatusLine().getStatusCode();
if (statusCode == HttpStatus.SC_OK) {InputStream is = httpResponse.getEntity().getContent();// do something with the input stream
}