juneau-doc/docs/Topics/06.juneau-rest-server/11.HandlingFormPosts.html

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Handling Form Posts

<p>
	The best way to handle a form post is usually by using an input bean.
	The following is a class that takes in URL-Encoded form post of the 
	form <l>"aString=foo&amp;aNumber=123&amp;aDate=2001-07-04T15:30:45Z"</l>.
</p>
<p class='bpcode w800'>				
	<ja>@Rest</ja>(
		path=<js>"/urlEncodedForm"</js>
	)
	<jk>public class</jk> UrlEncodedFormResource <jk>extends</jk> BasicRestServlet {
	
		<jd>/** POST request handler */</jd>
		<ja>@RestMethod</ja>(name=<jsf>POST</jsf>, path=<js>"/"</js>)
		<jk>public</jk> Object doPost(<ja>@Body</ja> FormInputBean input) <jk>throws</jk> Exception {
			<jc>// Just mirror back the request</jc>
			<jk>return</jk> input;
		}
	
		<jk>public static class</jk> FormInputBean {
			<jk>public</jk> String <jf>aString</jf>;
			<jk>public int</jk> <jf>aNumber</jf>;
			<ja>@Swap</ja>(TemporalCalendarSwap.IsoLocalDateTime.<jk>class</jk>)
			<jk>public</jk> Calendar <jf>aDate</jf>;
		}
	}		
</p>	
<p>
	Another possibility is to access the form parameters individually:	
</p>	
<p class='bpcode w800'>
	<jd>/** POST request handler */</jd>
	<ja>@RestMethod</ja>(name=<jsf>POST</jsf>, path=<js>"/"</js>)
	<jk>public</jk> Object doPost(<ja>@FormData</ja>(<js>"aString"</js>) String aString, <ja>@FormData</ja>(<js>"aNumber"</js>) <jk>int</jk> aNumber, <ja>@FormData</ja>(<js>"aDate"</js>) Calendar aDate) <jk>throws</jk> Exception {
		...
	}
</p>
<p>
	The advantage to the form input bean is that it can handle any of the parsable types (e.g. JSON, XML...) 
	in addition to URL-Encoding.  
	The latter approach only supports URL-Encoding.
</p>
<div class='warn'>
	If you're using form input beans, DO NOT use the <l>@FormData</l> attribute or 
	{@link oajr.RestRequest#getParameter(String)} method since this will cause the 
	underlying JEE servlet to parse the HTTP body as a form post.
	<br>Your input bean will end up being null since there won't be any content left after the servlet 
	has parsed the body of the request.
	<br>This applies to WHENEVER you use <l>@Body</l> or {@link oajr.RestRequest#getBody()}
</div>