Checking which submit button was clicked - forms

Question

I am devoloping a web application using J2EE and Spring Roo as framework.
I want to create a form with two submit buttons:
One for save and continue
Another for save and finish
<form action="mycontroller" method="post">
<input type="submit" value="Save and continue"/>
<input type="submit" value="Save and finish"/>
</form>
So I can choose to either store the data in the database and add more entries or to store the data and finish the process.
How can I check what submit button was clicked in the method of the controller that processes the action?
public class MyController {
void actionMethod(...) {
// check which submit was clicked
}
}

Answer 1

You should add a name field to both buttons:
<input type="submit" name="button" value="Save and continue"/>
<input type="submit" name="button" value="Save and finish"/>
Once in the controller, you can recover the element by this name field and check its value field:
String field = request.getParameter("button");
if ("Save and continue".equals(button)){
// Do stuff
}
else if ("Save and finish".equals(button)){
// Do a different stuff
}
else {
// None of them were pressed
}
Or also you can use a different name value for both buttons:
<input type="submit" name="button1" value="Save and continue"/>
<input type="submit" name="button2" value="Save and finish"/>
In your controller:
String button1 = request.getParameter("button1");
String button2 = request.getParameter("button2");
if (button1 != null){
// Do stuff
}
else if (button2 != null){
// Do a different stuff
}
else {
// None of them were pressed
}
Second solution is preferred because it doesn't depend on the value of the elements

Answer 2

To reduce if-else if you can, and benefit from Spring framework to handle these mapping, try the following solution (if you don't have many meta parameters to send in the form):
<form action="AddToCartListController" method="post">
<input type="submit" value="Save and continue"/>
</form>
<form action="CommitCartListController" method="post">
<input type="submit" value="Save and finish"/>
</form>
...
public class CartListController {
void AddToCartListController(...) {
// business code
}
void CommitCartListController(...) {
// business code
}
}
// ... or ...
public class AddToCartListController {
void actionMethod(...) {
// business code
}
}
public class CommitCartListController {
void actionMethod(...) {
// business code
}
}
and define a proper mapping in Spring configuration.