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How can i get the filename from a string type link

With Retrofit, I get the url data in string data type, but I need the file name inside the url, how can I get it?
I've visited many websites but I couldn't find any results about it.

Try this in Kotlin
url.substringAfterLast("/").substringBeforeLast(".")

How to send JSON as a parameter in url using Spring RestTemplate?

I am trying to achieve same thing as this: How to use query parameter represented as JSON with Spring RestTemplate?, sending JSON string as a URL parameter in restTemplate.exchange().
The accepted answer mentions that sending JSON object as request parameter is generally not a good idea since you will probably face problem with curly brackets inside JSON. That is exactly what is happening when I am trying to make a GET call to an API. Since this is an API from another system, I cannot ask them to change the format and will have to call the GET endpoint, passing JSON as parameter. How can I achieve this in restTemplate.exchange() call?
Note: The mentioned related question does not guide on how to overcome this problem and I do not have enough reputation to comment on it to ask the author of the answer.

Answering my own question. While it is a bad idea to pass JSON like this in a query/url parameter, there is a workaround as suggested here: https://jira.spring.io/browse/SPR-9220?focusedCommentId=76760&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-76760.
Replicating the code here in case this link goes dead:
String url = "http://localhost:8983/solr/select?wt=json&indent=true&fl=*&q=*:*&fq={!geofilt}&sfield=venue_location&pt=28.0674,-80.5595&d=25";
URI uri = UriComponentsBuilder.fromUriString(url).build().encode().toUri();
System.out.println(uri);
// http://localhost:8983/solr/select?wt=json&indent=true&fl=*&q=*:*&fq=%7B!geofilt%7D&sfield=venue_location&pt=28.0674,-80.5595&d=25
Basically, instead of passing url having JSON query/url parameters as a string, pass it as a URI. Then call exchange method as before, but with URI instead of String:
restTemplate.exchange(uri, HttpMethod.GET, requestEntity, String.class)

If this is 3rd party API and you cannot control or change JSON processing on backend side - there is no solution. Even if you will encode with URLEncoder - there is no guarantee that API backend would process such request correctly.

You can use URLEncoder class to encode the URL in exchange method, e.g.:
String url = "http://www.yoursite.com/api?param={\"some_key\":\"some_value\"}";
System.out.println(URLEncoder.encode(url, StandardCharsets.UTF_8.name()));
This will encode the characters (like braces and double quotes) and server then will decode it back to json.

How to post a big string/json using AJAX on Play Framework 1.4.x

I have a JSON that looks more or less like this:
{"id":"id","date":"date","csvdata":"csvdata".....}
where csvdata property is a big amount of data in JSON format too.
I was trying to POST this JSON using AJAX in Play! Framework 1.4.x so I sended just like that, but when I receive the data in the server side, the csvdata looks like [object Object] and stores it in my db.
My first thought to solve this was to send the csvdata json in string format to store it like a longtext, but when I try to do this, my request fails with the following error:
413 (Request Entity Too Large)
And Play's console show me this message:
Number of request parameters 3623 is higher than maximum of 1000, aborting. Can be configured using 'http.maxParams'
I also tried to add http.maxParams=5000 in application.conf but the only result is that Play's console says nothing and in my database this field is stored as null.
Can anyone help me, or maybe suggest another solution to my problem?
Thanks you so much in advance.

Is it possible that you sent "csvdata" as an array, not a string? Each element in the array would be a separate parameter. I have sent 100KB strings using AJAX and not run into the http.maxParams limit. You can check the contents of the request body using your browser's developer tools.
If your csvdata originates as a file on the client's machine, then the easiest way to send it is as a File. Your controller action would look like:
public static void upload(String id, Date date, File csv) {
...
}
When Play! binds a parameter to the File type, it writes the contents of the parameter to a temporary file which you can read in. (This avoids running out of memory if a large file is uploaded.) The File parameter type was designed for a normal form submit, but I have used it in AJAX when the browser supported some HTML5 features (File API and Form Data).

How to get JSON content from a RESTful server to a Android client?

I've built a REST server that automatically retrieves data from my database and returns it as JSON. I want to know, how I can get this JSON content to my mobile and turn it into a string so that I can store this in the mobile's database.

First you need to be able to parse your JSON string. For a simple parser I gave an answer earlier here:
getting Json result in Android
Just parse through the list and add them to the database. There are different database tutorials out there.
Database tutorial: http://www.vogella.de/articles/AndroidSQLite/article.html
To make it as easy as possible try to find out small tutorials for different sub tasks like REST to JSON and database handler.
Here is a tutorial for JSON parsing from a REST webservice:
http://www.josecgomez.com/2010/04/30/android-accessing-restfull-web-services-using-json/
Here is another more simple JSON example:
http://inchoo.net/mobile-development/android-development/simple-android-json-parsing-example-with-output-into-listactivity/

Selenium 2: Detect content type of link destinations

I am using the Selenium 2 Java API to interact with web pages. My question is: How can i detect the content type of link destinations?
Basically, this is the background: Before clicking a link, i want to be sure that the response is an HTML file. If not, i need to handle it in another way. So, let's say there is a download link for a PDF file. The application should directly read the contents of that URL instead of opening it in the browser.
The goal is to have an application which automatically knows wheather the current location is an HTML, PDF, XML or whatever to use appropriate parsers to extract useful information out of the documents.
Update
Added bounty: Will reward it to the best solution which allows me to get the content type of a given URL.

As Jochen suggests, the way to get the Content-type without also downloading the content is HTTP HEAD, and the selenium webdrivers does not seem to offer functionality like that. You'll have to find another library to help you with fetching the content type of an url.
A Java library that can do this is Apache HttpComponents, especially HttpClient.
(The following code is untested)
HttpClient httpclient = new DefaultHttpClient();
HttpHead httphead = new HttpHead("http://foo/bar");
HttpResponse response = httpclient.execute(httphead);
BasicHeader contenttypeheader = response.getFirstHeader("Content-Type");
System.out.println(contenttypeheader);
The project publishes JavaDoc for HttpClient, the documentation for the HttpClient interface contains a nice example.

You can figure out the content type will processing the data coming in.
Not sure why you need to figure this out first.
If so, use the HEAD method and look at the Content-Type header.

You can retrieve all the URLs from the DOM, and then parse the last few characters of each URL (using a java regex) to determine the link type.
You can parse characters proceeding the last dot. For example, in the url http://yoursite.com/whatever/test.pdf, extract the pdf, and enforce your test logic accordingly.
Am I oversimplifying your problem?