My servlet is mapped with <url-pattern> /controller/*/* </url-pattern> my url is like this controller/12341/ABC123 will always like this but values can be changed.
I am trying to get value of first * and second * which presents serial & mac
I write following code but it return only last part ACB123
String mac= request.getPathInfo().replace("/", "");
How can I get both vaules?
If I read the servlet spec correctly you cannot have multiple wildcards. Try
<url-pattern>/controller/*</url-pattern>
And then:
String[] parts = request.getPathInfo().split("/");
String serial = parts[1]; // before last index
String mac = parts[2]; // last index
Of course you will need some error handling for this.
On a related note: Pure servlet API is a pain to work with. If you have just this only servlet or are constrained somehow, this might be OK. However if you have more servlets and even need HTTP request parameter handling, parsing etc., using a framework like Spring WebMVC might be more appropriate.
Related
How can i send an Array with a HTTP Get request?
I'm Using GWT client to send the request.
I know this post is really old, but I have to reply because although BalusC's answer is marked as correct, it's not completely correct.
You have to write the query adding "[]" to foo like this:
foo[]=val1&foo[]=val2&foo[]=val3
That depends on what the target server accepts. There is no definitive standard for this. See also a.o. Wikipedia: Query string:
While there is no definitive standard, most web frameworks allow multiple values to be associated with a single field (e.g. field1=value1&field1=value2&field2=value3).[4][5]
Generally, when the target server uses a strong typed programming language like Java (Servlet), then you can just send them as multiple parameters with the same name. The API usually offers a dedicated method to obtain multiple parameter values as an array.
foo=value1&foo=value2&foo=value3
String[] foo = request.getParameterValues("foo"); // [value1, value2, value3]
The request.getParameter("foo") will also work on it, but it'll return only the first value.
String foo = request.getParameter("foo"); // value1
And, when the target server uses a weak typed language like PHP or RoR, then you need to suffix the parameter name with braces [] in order to trigger the language to return an array of values instead of a single value.
foo[]=value1&foo[]=value2&foo[]=value3
$foo = $_GET["foo"]; // [value1, value2, value3]
echo is_array($foo); // true
In case you still use foo=value1&foo=value2&foo=value3, then it'll return only the first value.
$foo = $_GET["foo"]; // value1
echo is_array($foo); // false
Do note that when you send foo[]=value1&foo[]=value2&foo[]=value3 to a Java Servlet, then you can still obtain them, but you'd need to use the exact parameter name including the braces.
String[] foo = request.getParameterValues("foo[]"); // [value1, value2, value3]
I sent one request as URL with data to servlet, But by default servlet is modifying the data and sending as request. Can you please suggest how to maintain the request URL with data which i passed to servlet should remain same ?
Example:- when i am passing the data to servlet
http://localhost/helloservlet/servlet/ppd.abcd.build.coupons.CouponValueFormatterServlet?dsn=frd_abc_abcde&lang=ENG&val=PRCTXT|12345 &ABCDEFG
when it using the above url in servelt as request , like string abc = request.getParameter("val"), the val attribute is trimmed automatically and assigned as " val=PRCTXT|12345" but it supposed to be like " val = PRCTXT|12345 &ABCDEFG ". Please help me on this.
The servlet interprets each & in the URL as the start of a new parameter. So when it sees &ABCDEFG, it thinks you are sending a new parameter called ABCDEFG with no value (though this is technically a "keyless value" according to the specifications).
Two things to fix this, first is when you want to actually send an &, use %26 instead. This will be skipped by the code that divides up the parameters, but converted to a real & in the parameter's value.
Second is to replace spaces with +. Spaces in URLs work sometimes but can be problematic.
So your actual request URL should look like this:
http://localhost/helloservlet/servlet/ppd.abcd.build.coupons.CouponValueFormatterServlet?dsn=frd_abc_abcde&lang=ENG&val=PRCTXT|12345+%26ABCDEFG
If you're building these parameters in javascript, you can use encodeURIComponent() to fix all problem characters for you. So you could do something like this:
var userInput = *get some input here*
var addr = 'http://www.example.com?param1=' + encodeURIComponent(userInput);
In my web application I'm trying to prevent users from inserting JavaScript in the freeText parameter when they're running a search.
To do this, I've written code in the header Velocity file to check whether the query string contains a parameter called freeText, and if so, use the replace method to replace the characters within the parameter value. However, when you load the page, it still displays the original query string - I'm unsure on how to replace the original query string with my new one which has the replaced characters.
This is my code:
#set($freeTextParameter = "$request.getParameter('freeText')")
freeTextParameter: $freeTextParameter
#if($freeTextParameter)
##Do the replacement:
#set($replacedQueryString = "$freeTextParameter.replace('confirm','replaced')")
replacedQueryString after doing the replace: $replacedQueryString
The query string now: $request.getQueryString()
The freeText parameter now: $request.getParameter('freeText')
#end
In the code above, the replacedQueryString variable has changed as expected (ie the replacement has been carried out as expected), but the $request.getQueryString() and $request.getParameter('freeText') are still the same as before, as if the replacement had never happened.
Seeing as there is a request.getParameter method which works fine for getting the parameters, I assumed there would be a request.setParameter method to do the same thing in reverse, but there isn't.
The Java String is an immutable object, which means that the replace() method will return an altered string, without changing the original one.
Since the parameters map given by the HttpServletRequest object cannot be modified, this approach doesn't work well if your templates rely on $request.getParameter('freeText').
Instead, if you rely on VelocityTools, then you can rather rely on $params.freeText in your templates. Then, you can tune your WEB-INF/tools.xml file to make this parameters map alterable:
<?xml version="1.0">
<tools>
<toolbox scope="request">
<tool key="params" readOnly="false"/>
...
</toolbox>
...
</tools>
(Version 2.0+ of the tools is required).
Then, in your header, you can do:
#set($params.freeText = params.freeText.replace('confirm','replaced'))
I managed to fix the issue myself - it turned out that there was another file (which gets called on every page) in which the $!request.getParameter('freeText')" variable is used. I have updated that file so that it uses the new $!replacedQueryString variable (ie the one with the JavaScript stripped out) instead of the existing "$!request.getParameter('freeText')" variable. This now prevents the JavaScript from being executed on every page.
So, this is the final working code in the header Velocity file:
#set($freeTextParameter = "$!m.request.httpRequest.getParameter('freeText')")
#if($freeTextParameter)
#set($replacedQueryString = "$freeTextParameter.replace('confirm','').replace('<','').replace('>','').replace('(','').replace(')','').replace(';','').replace('/','').replace('\"','').replace('&','').replace('+','').replace('script','').replace('prompt','').replace('*','').replace('.','')")
#end
I need to send a request using Java to an existing REST service using GET with multiple input parameters.
If the initial url for the calculation I want is:
https://api.restservice123.com/api/calculate
I want to make a calc object e with the following parameters:
calcObj e = new calcObj();
e.token="token_ABC123";
e.country="US";
e.amount = 100;
e.price = 24;
e.customer = "bob";
the url should look something like this:
https://api.restservice123.com/api/calculate?token=token_ABC123&country=US&amount=100&price=24&customer=bob
Is there any framework that will combine the parameters from the calc object and reformat them into the url appropirate format and combine them with the api url?
I ended up making a method in the calc object that puts all the non null parameters into a list of strings and combines them using a Joiner from google common and connecting to the url using an HttpURLConnection. But this method looks bad as I'm hoping there's something out there that can already do all of this much more elegantly, but I couldn't find it.
The URIBuilder class works well for this. It has a method setParameters(java.util.List) that takes a list of name value pairs and builds a URI from them.
For a very simple ajax name lookup, I'm sending an id from the client webpage to the server (Tomcat 5.5, Java 5), looking it up in a database and returning a string, which is assigned to a javascript variable back in the client (and then displayed).
The javascript code that receives the value is pretty standard:
//client code - javascript
xmlHttp.onreadystatechange=function() {
if (xmlHttp.readyState==4) {
var result = xmlHttp.responseText;
alert(result);
...
}
...
}
To return the string, I originally had this in the server:
//server code - java
myString = "...";
out.write(myString.getBytes("UTF-8"));
Which worked perfectly, if unsafe. Later, I replaced it with:
import org.apache.commons.lang.StringEscapeUtils;
...
myString = "...";
out.write(StringEscapeUtils.escapeJavaScript(myString).getBytes("UTF-8"));
But while safer, the resulting string can't be properly displayed if it contains special chars like "ñ".
For instance, using:
escapeJavaScript("años").getBytes("UTF-8");
sends:
an\u00F1os
to the client.
The question: is there a simple way to parse the resulting string in Javascript or is there an alternate escape function I can use in java that would prevent this issue?
The following works in every browser I've tried:
javascript:alert("a\u00F1os");
Perhaps your string is being escaped twice by mistake.
Actually, now that I read it over, I think I actually don't need to escape the string I'm sending back at all... That is, StringEscapeUtils.escapeJavaScript would be useful if the resulting value was printed in the page, like:
//javascript code with inline struts
var myJavasriptString = "<%=myJavaString%>";
Or am I missing something and there would still be a valid reason to do the escape in the original case? (when it is returned as a series of bytes back to an ajax onreadystatechange handler and assigned to a js variable)