如何使用Apache HttpClient发布JSON请求？

Question

我有类似以下内容：

final String url = "http://example.com";

final HttpClient httpClient = new HttpClient();
final PostMethod postMethod = new PostMethod(url);
postMethod.addRequestHeader("Content-Type", "application/json");
postMethod.addParameters(new NameValuePair[]{
        new NameValuePair("name", "value)
});
httpClient.executeMethod(httpMethod);
postMethod.getResponseBodyAsStream();
postMethod.releaseConnection();

它不断返回500。服务提供商说我需要发送JSON。Apache HttpClient 3.1+如何完成？

Answer 1

Apache
HttpClient对JSON一无所知，因此您需要分别构造JSON。为此，我建议从json.org检出简单的JSON-
java
库。（如果“ JSON-
java”不适合您，则json.org列出了大量可用不同语言提供的库。）

生成JSON后，您可以使用以下代码进行发布

StringRequestEntity requestEntity = new StringRequestEntity(
    JSON_STRING,
    "application/json",
    "UTF-8");

PostMethod postMethod = new PostMethod("http://example.com/action");
postMethod.setRequestEntity(requestEntity);

int statusCode = httpClient.executeMethod(postMethod);

编辑

注-问题中要求的上述答案适用于Apache HttpClient 3.1。但是，要帮助任何寻求针对最新Apache客户端实现的人：

StringEntity requestEntity = new StringEntity(
    JSON_STRING,
    ContentType.APPLICATION_JSON);

HttpPost postMethod = new HttpPost("http://example.com/action");
postMethod.setEntity(requestEntity);

HttpResponse rawResponse = httpclient.execute(postMethod);