如何将字符串数据(JSONObject.toString())
发送到URL。我想在util类中编写一个静态方法来执行此操作。我希望方法签名如下所示
公共静态字符串 postData (String url, String postData) 抛出 SomeCustomException
字符串url的格式应该是什么
返回的 String 是来自 服务器的响应,作为 json 数据的字符串表示形式。
package my.package;
import my.package.exceptions.CustomException;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URLDecoder;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.DefaultHttpClient;
public class ConnectionUtil {
public static String postData(String url, String postData)
throws CustomException {
// Create a new HttpClient and Post Header
InputStream is = null;
StringBuilder sb = null;
String result = "";
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost();
httppost.setHeader("host", url);
Log.v("ConnectionUtil", "Opening POST connection to URI = " + httppost.getURI() + " url = " + URLDecoder.decode(url));
try {
httppost.setEntity(new StringEntity(postData));
// Execute HTTP Post Request
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
is = entity.getContent();
} catch (Exception e) {
Log.e("log_tag", "Error in http connection " + e.toString());
e.printStackTrace();
throw new CustomException("Could not establish network connection");
}
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(
is, "utf-8"), 8);
sb = new StringBuilder();
sb.append(reader.readLine() + "\n");
String line = "0";
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
result = sb.toString();
} catch (Exception e) {
Log.e("log_tag", "Error converting result " + e.toString());
throw new CustomException("Error parsing the response");
}
Log.v("ConnectionUtil", "Sent: "+postData);
Log.v("ConnectionUtil", "Got result "+result);
return result;
}
}
尝试使用此方法,其中strJsonRequest是要发布的json字符串,strUrl是要发布strJsonRequest的Url
public String urlPost(String strJsonRequest, String strURL) throws Exception
{
try
{
URL objURL = new URL(strURL);
connection = (HttpURLConnection)objURL.openConnection();
connection.setDoInput(true);
connection.setDoOutput(true);
connection.setAllowUserInteraction(false);
connection.setUseCaches(false);
connection.setConnectTimeout(TIMEOUT_CONNECT_MILLIS);
connection.setReadTimeout(TIMEOUT_READ_MILLIS);
connection.setRequestMethod("POST");
connection.setRequestProperty("Accept-Charset", "utf-8");
connection.setRequestProperty("Content-Type", "application/json; charset=utf-8");
connection.setRequestProperty("Content-Length", ""+strJsonRequest.toString().getBytes("UTF8").length);
DataOutputStream outputStream = new DataOutputStream(connection.getOutputStream());
byte [] b = strJsonRequest.getBytes("UTF-8");
outputStream.write(b);
outputStream.flush();
inputstreamObj = (InputStream) connection.getContent();//getInputStream();
if(inputstreamObj != null)
strResponse = convertStreamToString(inputstreamObj);
}
catch(Exception e)
{
throw e;
}
return strResponse;
}
方法 convertStreamToString() 如下所示
private static String convertStreamToString(InputStream is)
{
/*
* To convert the InputStream to String we use the BufferedReader.readLine()
* method. We iterate until the BufferedReader return null which means
* there's no more data to read. Each line will appended to a StringBuilder
* and returned as String.
*/
BufferedReader reader = null;
try {
reader = new BufferedReader(new InputStreamReader(is));
} catch (Exception e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
StringBuilder sb = new StringBuilder();
String line = null;
try
{
while ((line = reader.readLine()) != null)
{
sb.append(line + "\n");
}
}
catch (IOException e)
{
e.printStackTrace();
}
finally
{
try
{
is.close();
}
catch (IOException e)
{
e.printStackTrace();
}
}
return sb.toString();
}
好吧,以下是我对你的问题的想法
> < li>
首先,您应该使用< code>POST方法将数据发送到服务器。这很容易,在Android系统中也绝对可行。发送< code>POST数据的简单代码片段如下:
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost(
"http://yourserverIP/postdata.php");
String serverResponse = null;
try {
List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
nameValuePairs.add(new BasicNameValuePair("datakey1", dataValue1));
nameValuePairs.add(new BasicNameValuePair("datakey2",
dataValue2));
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
HttpResponse response = httpclient.execute(httppost);
serverResponse = response.getStatusLine().toString();
Log.e("response", serverResponse);
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
上面的代码将数据发送到服务器上的PHP脚本< code>postdata。
String jsonData = EntityUtils.toString(serverResponse.getEntity());
我认为在您的代码中,基本问题是由您使用StringEntity
将参数POST
到URL的方式引起的。检查以下代码是否有助于使用 StringEntity
将数据发布到服务器。
// Build the JSON object to pass parameters
JSONObject jsonObj = new JSONObject();
jsonObj.put("username", username);
jsonObj.put("data", dataValue);
// Create the POST object and add the parameters
HttpPost httpPost = new HttpPost(url);
StringEntity entity = new StringEntity(jsonObj.toString(), HTTP.UTF_8);
entity.setContentType("application/json");
httpPost.setEntity(entity);
HttpClient client = new DefaultHttpClient();
HttpResponse response = client.execute(httpPost);
希望这有助于解决您的问题。谢谢。
我正在Micronaut中编写一个java库模块,它有一个http客户端。这个想法是我的微服务将使用这个库作为jar依赖项并使用http客户端。 问题陈述:我想在不使用 的情况下配置我的 HttpClient。 为什么我不想用application.yml?-因为使用此库的微服务也将拥有自己的< code>application.yml,并且在构建jar时,需要合并两个< code>applica
问题内容: 两者之间有很大的区别,最好使用哪一个? 问题答案: :Apache的子类,配置了合理的默认设置和Android的注册方案,并允许用户添加类。该客户端处理cookie,但默认情况下不保留它们。要保留Cookie,只需将Cookie存储添加到 [ API ]
我正在Java控制台应用程序中使用ApacheHttpClient 4.5(具有fluent接口)。我注意到,它的默认超时值似乎是无限的,但我必须为我发送的请求使用非无限超时值。我想对所有请求使用相同的超时值。 如何全局设置默认的连接超时和套接字超时值,以便不必在代码中发送请求的每个位置都设置它们?(记住我使用的是流畅的界面) 示例: 现在,在我的代码中发送请求的每个地方,我都会执行如下操作:(简
我目前正在使用vscode和apachepoi,创建了一个程序来自动创建<code>。xlsx编程并让A1单元输入一个名为“Tester”的字符串,然后弹出错误。 我程序中的代码: 错误代码: 嗯.xml( Apache POI对我来说是新的,请帮助我,我会非常感激,非常感谢。
入口方法或适配器或其他原因导致异常时需要走的视图,依然是打开MainModule,加入代码 @Fail("jsp:jsp.500") 含义就是内部重定向到/WEB-INF/jsp/500.jsp页面 打开web.xml, 加入如下配置 <error-page> <error-code>500</error-code> <location>/WEB-INF/
这个项目以json交互为主,所以,默认用json视图好了. 打开MainModule,加入代码 @Ok("json:full") 这里的json指UTF8JsonView类, 后面的full是JsonFormat的其中一种内置格式的缩写: 默认 -- 忽略空值,换行,key不带双引号, 新版jquery不兼容 full -- 不忽略空值,换行,key带双引号, 新版jquery兼容 compac