如何编程实现HTTP表单操作

Question

需要对一个ERP系统中的数据进行批量更新，因为数据量太多，又不能直接操作数据库，所以想通过JAVA编程来实现，现在没有头绪，想请教各位有没有这方面的高招？

Answer 1

给你两种方法供选择：
1），利用httpclient4.× 写一个http的客户端，模拟浏览器请求，如下：
[code]
public void post(List payload) throws UmcException,
ClientProtocolException, IOException {
HttpPost post = new HttpPost(uri);
HttpEntity result = null;
try {
UrlEncodedFormEntity entity = new UrlEncodedFormEntity(payload,
charset);
post.setEntity(entity);
if (LOG.isDebugEnabled()) {
LOG.debug("sending:" + payload);
}

        HttpResponse response = _httpClient.execute(post);
        StatusLine statusLine = response.getStatusLine();
        if (statusLine.getStatusCode() != HttpStatus.SC_OK) {
            result = response.getEntity();
            StringBuilder msg = new StringBuilder();
            msg.append("http response with code "
                    + statusLine.getStatusCode());
            msg.append("\n");
            msg.append("post request: " + post.getURI());
            msg.append("\n");
            msg.append(statusLine.getReasonPhrase());
            if (result != null) {
                msg.append("\n\n");
                msg.append(EntityUtils.toString(result, "UTF-8"));
                msg.append("\n\n");
            }
            throw new UmcException(msg.toString());
        }
        if (response.getEntity() != null) {
            BufferedReader reader = new BufferedReader(
                    new InputStreamReader(
                            response.getEntity().getContent(), "UTF-8"));
            String line = null;
            while ((line = reader.readLine()) != null) {
                if (line.indexOf("success") < 0)
                    System.out.println(line);
            }
        }
    } finally {
        if (result != null)
            try {
                EntityUtils.consume(result);
            } catch (IOException e) {
            }
        post.abort();
    }
}

[/code]
uri是请求的地址，charset是编码“UTF-8”,List就是表单参数集
[code]

ClientConnectionManager ccManager = new ThreadSafeClientConnManager();
HttpClient _httpClient = new DefaultHttpClient(ccManager);
[/code]
这是从我的项目测试代码中直接copy出来的，你看着改吧。

第二种方法：采用JDK的HttpConnection构造http客户端，
[code]
////发送
HttpURLConnection conn = null;
try {
URL url = new URL(ECP_URL);
conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("POST");
conn.setRequestProperty("Content-Type",
"application/x-www-form-urlencoded");
conn.setUseCaches(false);
conn.setDoOutput(true);
OutputStreamWriter osw = new OutputStreamWriter(
conn.getOutputStream());
StringBuffer sb = new StringBuffer();
addPair(sb, "p1", "p1value");
addPair(sb, "p2", "p2value");
osw.write(sb.substring(0, sb.length() - 1));
osw.flush();
BufferedReader reader = new BufferedReader(
new InputStreamReader(conn.getInputStream()));
String line = null;
sb = new StringBuffer();
while ((line = reader.readLine()) != null) {
sb.append(line);
}
line = sb.toString();
// 处理返回的字符串line
return;
////
} catch (IOException e) {
// handle e
} finally {
if (conn != null)
conn.disconnect();
}///发送结束
[/code]
addPair方法：
[code]
public static void addPair(StringBuffer sb, String name, String value) {
if (value == null) {
return;
}
sb.append(name);
sb.append("=");
sb.append(value);
sb.append("&");
}
[/code]