Versions Compared

Key

  • This line was added.
  • This line was removed.
  • Formatting was changed.
Comment: removed some unneeded white-spaces.

...

This feature will automatically compile your .groovy source files, turn them into bytecode, load the Class and cache it until you change the source file.

Here's a simple example to show you the kind of thing you can do from a Groovlet.
Notice the use of implicit variables to access the session, output & request. Also notice that this is more like a script as it doesn't have a class wrapper.

Code Block
java
java

if (!session) {
  session = request.getSession(true);
}

if (!session.counter) {
  session.counter = 1
}

println """
<html>
    <head>
        <title>Groovy Servlet</title>
    </head>
    <body>
Hello, ${request.remoteHost}: ${session.counter}! ${new Date()}
    </body>
</html>
"""
session.counter = session.counter + 1

...

variable name

bound to

note

request

ServletRequest

-

response

ServletResponse

-

context

ServletContext

unlike Struts

application

ServletContext

unlike Struts

session

getSession(false)

can be null! see (star)
A

params

 

a Map object

headers

 

a Map object

out

response.getWriter()

see (star)
B

sout

response.getOutputStream()

see (star)
B

html

new MarkupBuilder(out)

see (star)
B

(star) A The session variable is only set, if there was already a session object. See the 'if (session == null)' checks in the examples above.

...

Put the following in your web.xml:

Code Block
xml
xml
<servlet>
<servlet-name>Groovy</servlet-name>
<servlet-class>groovy.servlet.GroovyServlet</servlet-class>
</servlet>

<servlet-mapping>
<servlet-name>Groovy</servlet-name>
<url-pattern>*.groovy</url-pattern>
</servlet-mapping>

Then all the groovy jar files into WEB-INF/lib. You should only need to put the groovy.jar, the antlr.jar and the asm.jar. Or copy the groovy-all-xyz.jar into WEB-INF/lib - this almost all jar contains the antlr and asm jars.
Now put the .groovy files in, say, the root directory (i.e. where you would put your html files). The groovy servlet takes care of compiling the .groovy files.

So for example using tomcat you could edit tomcat/conf/server.xml like so:

Code Block
xml
xml
<Context path="/groovy" docBase="c:/groovy-servlet"/>

Then access it with http://localhost:8080/groovy/hello.groovy