I'm using Java EE technology for my web application. And I use Apache Solr for my search engine. AFAIK, after I config Solr successfully, Solr is running as a Restful service.
So, under my servlet, I try to call this service as another console application I do before. Here is a sample code is used to get json data from an url:
/** Get Data Fom URL Using GET Method */
public static String getResponseFromGetRequest(String url) {
HttpClient httpClient = new DefaultHttpClient();
HttpGet httpGet = new HttpGet(url);
/** after prepare for data. prepare for sending */
try {
/**
* HttpResponse is an interface just like HttpGet
* therefore we can't initialize them
*/
HttpResponse httpResponse = httpClient.execute(httpGet);
return parseHttpResponse(httpResponse);
} catch (ClientProtocolException ex) {
ex.printStackTrace();
} catch (IOException ex) {
ex.printStackTrace();
}
return null;
}
But the package org.apache.http.impl.client.DefaultHttpClient is not available (under tomcat server at least). So, I think maybe there are some problems here. That we cannot call another service in servlet, right? If my guess is true, how can I fix this problem?
A brief code on using an API available in java to interact with solr(you don't need to know or care about servlets, httpclients, nothing).
HttpSolrServer server = new HttpSolrServer("your restful url goes here");
SolrQuery query = new SolrQuery();
QueryResponse response = server.query(query);
List<MyClass> beans = response.getBeans(MyClass.class);
server should probably be a spring bean, it's the java representation (proxy object) of your running solr server.
query is a query to run against the server, configure this to specify what you want from solr.
response is the answer to the request.
beans are objects which are straight from solr itself (as far as i remember, your solr fields get mapped to the java object's fields by field name, no restrictions at all).
note that server has a lot of ways to do simple operations without anything explicit, like server.addBean(myBean);
Here is how to get Solrj in maven:
<dependency>
<groupId>org.apache.solr</groupId>
<artifactId>solr-solrj</artifactId>
<version>4.5.1</version>
</dependency>
If you don't have maven:
http://mvnrepository.com/artifact/org.apache.solr/solr-solrj/4.10.3
click on "Download ( JAR )".
Related
I'm using the WSRequest class to make requests to an external web-service in my Play web-application.
Here's a small snippet of the code I'm using to make SOAP calls:
WSRequest req = WS.url("http://mydomain.com/soap");
req.setHeader("Content-Type", "text/xml;charset=UTF-8");
Map<String, Object> args = new HashedMap();
args.put("countryCode", countryCode);
req.body(requestTemplate.render(args));
HttpResponse res = req.post();
Document document=null;
try{
document = res.getXml();
}catch(RuntimeException e){
System.out.println(res.getString());
throw e;
}
I'd like SOAP calls made to this endpoint to show up on the "External Services" page of New Relic. How can I instrument my code in order to accomplish this? I haven't been able to find much information about this in the documentation except for a Ruby example.
At this time, the New Relic Java agent only notices external calls made with the following methods:
HttpURLConnection
CommonsHttp
Jets3t
S3
AsyncHttpClient
The Play WS API is not among those and, at this time, there is no way to for the user to do anything to modify the behavior.
I would recommend contacting New Relic tech support with a feature request to add external call support for Play's WS API.
You can now implement custom network tracking:
https://docs.newrelic.com/docs/mobile-sdk-api/android-api#track-custom
I have an app that makes http requests to a remote server. I do this with the following code:
HttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost("myURL");
try {
ArrayList<BasicNameValuePair> postVariables = new ArrayList<BasicNameValuePair>(2);
postVariables.add(new BasicNameValuePair("key","value"));
httpPost.setEntity(new UrlEncodedFormEntity(postVariables));
HttpResponse response = httpClient.execute(httpPost);
String responseString = EntityUtils.toString(response.getEntity());
if (responseString.contains("\"success\":true")){
//this means the request succeeded
} else {
//failed
}
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
This goes really well, but one of our customers has set up an APN that requires requests to go via a certain proxy server. If I add the following to the request this works, the request gets rerouted via the proxy to the server:
HttpHost httpHost = new HttpHost("proxyURL",8080);
httpClient.getParams().setParameter(ConnRoutePNames.DEFAULT_PROXY, httpHost);
So far so good, however, I use a library that makes some http requests as well. The library's code is not accesible for me, so I can't add those two lines to the code. I contacted the creators of that library, and they told me it should be possible to set up the android environment so that all requests will automatically go through the proxy. Is there something like that? I didn't find anything on google.
I'm basically looking for a way to set the above two lines as a standard for all http requests. Please note that the APN does not set the proxy as a default for the entire phone, so apps will have to do this manually (and yes that means the majority of the apps don't work on that customer's phone).
It's been a year or two since I've needed to use it, but if I remember correctly, you can use the System.setProperty(String, String) in order to set an environment-wide setting for your application to route all HTTP traffic through a proxy. The properties that you should need to set are "http.proxyHost" and "http.proxyPort" and then use your HttpClient normally without specifying a proxy because the VM will handle routing requests.
Docs for more information about what I'm talking about can be found here: ProxySelector (just so you know what keys to use) and here for documentation about the actual System.setProperty(String, String) function
If that doesn't work for you, let me know and I'll try to dig out my old code that set a system-level proxy. BTW, it's really only "system-level" since each app runs in it's own Dalvik so you won't impact other app's network communications.
Context
I have a desktop JAVA application I use to upload files (blobs) to a google app blobstore.
Everything works fine with a direct connection to the Internet but it doesn't when connecting through an HTTP proxy (Squid) with authentication.
I am using httpClient 4.2.3 and I don't get any error or response. It just gets stuck when calling httpClient.execute(post).
Code
I added these lines to handle the proxy authentication and it works well when using URL to get a page:
System.setProperty("http.proxyUser", username);
System.setProperty("http.proxyPassword", password);
I tried those as well:
Authenticator.setDefault(
new Authenticator() {
#Override
public PasswordAuthentication getPasswordAuthentication() {
return new PasswordAuthentication(
username, password.toCharArray());
}
}
);
And from now on this is the same code that works when not using a proxy.
First of all I download a page where I get the url to use to post a file to the blobstore:
URL url = new URL("http://www.example.com/get-upload-url.jsp");
String urlWhereToPost=IOUtils.toString(url.openStream());
DefaultHttpClient client = new DefaultHttpClient ();
Here we prepare the multipart post:
HttpPost post
= new HttpPost( urlWhereToPost.trim() );
MultipartEntity entity
= new MultipartEntity( HttpMultipartMode.BROWSER_COMPATIBLE);
entity.addPart( "key"
, new FileBody(new File(jpgFilePath)
, "image/jpeg" )
);
post.setEntity((HttpEntity)entity);
And it is when calling execute that nothing happens (and it never get's to the next instruction):
HttpResponse execute = client.execute( post );
Tests
I have been trying several things but nothing worked:
In the beginning I thought the problem was using POST because GET works fine using URL()
but I tried using HttpClient to execute a GET and it gets stuck as well.
I used Wireshark to check the packets send to the proxy and I saw that when using URL() Wireshark recognizes the calls to the proxy as requests to execute a GET from the proxy. But when using httpClient it looks like the request is not well built because Wireshark shows a packet but doesn't recognize the inner request.
Then I tried building the POST using HttpURLConnection and it gets through the proxy and I get the answer from the server but it looks like I am not building it well because appengine doesn't find the file I send (but this would be another question...).
Conclusion
Anyone with the same problem? Any idea?
Your proxy settings are for the Java system classes. Apache HttpClient is supposed to be configured in a different way.
This link may help: Proxy authentication
I have a web service that I built... what I am trying to do now is send a simple request that contains a json query string from a Tapestry web app to that web service. I searched around and most people say to use Apache HttpClient to achieve this. Along with HttpClient I am using URIBuilder.
The Json object that I am trying to send looks like this
{"user":{"userEmail":"jdoe#gmail.com","firstName":"John","lastName":"Doe","phone":"203- 555-5555"},"password":"dead"}
*I realize the issues with the password being sent in plain text etc...
The url that works (tested by manually entering in a web browser and this web service already services an Android client and an iOS client) looks like this
http:// ##.##.###.##/createuser?json={"user":{"userEmail":"jdoe#gmail.com","firstName":"John","lastName":"Doe","phone":"203-555-5555"},"password":"dead"}
Here is the HttpClient code that I have mashed together from google'ing around trying to figure out why this wont work. Essentially what I am trying to do is create a URI with URIBuilder and then construct an HttpPost or HttpGet object with the newly built URI. But something is going wrong in the URIBuilding process. When I debug, an exception gets thrown when I try to set all the aspects of the URI.
Object onSuccess() throws ClientProtocolException, IOException, URISyntaxException{
// json = {"user":{"userEmail":"jdoe#gmail.com","firstName":"John","lastName":"Doe","phone":"203- 555-5555"},"password":"dead"}
String json = user.toJson();
URIBuilder builder = new URIBuilder();
// Error gets thrown when I step over the next line
builder.setScheme("http").setHost("##.###.##.###").setPort(8080).setPath("createuser").setQuery("json=" +json);
URI uri = builder.build();
HttpPost request = new HttpPost(uri);
DefaultHttpClient httpClient = new DefaultHttpClient();
String tmp = request.getURI().toString();
HttpResponse response = httpClient.execute(request);
index.setResponse(EntityUtils.toString(response.getEntity()));
return index;
The error that comes back when I step over the line that I commented in the code is
[ERROR] TapestryModule.RequestExceptionHandler Processing of request failed with uncaught exception:org.apache.http.client.utils.URLEncodedUtils.parse(Ljava/lang/String;Ljava/nio/charset/Charset;)Ljava/util/List;
java.lang.NoSuchMethodError:org.apache.http.client.utils.URLEncodedUtils.parse(Ljava/lang/String;Ljava/nio/charset/Charset;)Ljava/util/List;
I have tried a lot of other combinations of methods and objects to get this request to send off to the server correctly and nothing seems to work. Hopefully I am overlooking something relatively simple.
Thanks in advance for any guidance you can provide.
You most likely have the wrong version or two versions of the apache httpcomponents on your classpath. If you are running Tapestry it will print out all packages on the classpath on the error page. Investigate there, find which httpcomponents is loaded, figure out where it comes from and fix it.
If this does not work, you should share some of your runtime environment with us. Which servlet engine, running from which IDE or are you running from the command line. Are you using Maven? If so share your pom. Etc.
I am fairly new to Android programming and was wondering how I can get data from an SQL database in my Android app.
I currently have a PHP script that pulls the data I want from the SQL table but I'm not sure how to pull the data from the PHP script into my Java. How do I do this? I read something about SOAP. Is this the protocol I want to use?
Thanks
It depends. Where's the database, on the device, or on a server? If it's on the server, is the PHP code already a web app, or is it just a script?
In general, if the database is on the device, throw out the PHP and use JDBC to grab the data directly from Java. If the data is on the server, then turn the PHP script into a web app, and access that web app from Java. SOAP is certainly one protocol you can use for this, albeit a complex one that's often overkill. JSON or just plain text are many times better choices.
You can use the function below to get content from your PHP script
public static String get(String from) {
try {
HttpClient client = new DefaultHttpClient();
HttpGet get = new HttpGet(from);
HttpResponse responseGet = client.execute(get);
HttpEntity resEntityGet = responseGet.getEntity();
if (resEntityGet != null) return EntityUtils.toString(resEntityGet);
} catch (Exception e) {
Log.e("", e.toString());
}
return null;
}