Implement methods of an interface or abstract class

If a class is declared as implementing a certain interface or extending a class with abstract methods, it has to implement the methods of such interface or class. IntelliJ IDEA creates stubs for implemented methods , with the default return values for the primitive types, and null values for the objects.

Implement required methods

From the main menu, select Code | Implement methods or press Ctrl+I. You can also right-click anywhere in the class file, then click Generate Alt+Insert, and select Implement methods.
In the dialog that opens, select the methods to implement. If necessary, select the Copy JavaDoc checkbox to insert JavaDoc comments for the implemented methods .
Click OK.

Change method body

The code template used for implementing methods (Implemented method body) accepts predefined template variables from the File Header include template (such as ${USER}, ${DATE}, and so on)

For example, consider the following file template:

            #if ( $RETURN_TYPE != "void" )return $DEFAULT_RETURN_VALUE;#end
            // TODO ($USER, $DATE):To change the body of an implemented method, use File | Settings - Editor -  File and Code Templates.
        

Provided that the implemented interface contains two methods, this template expands into the following code:

            @Override
            public void hunt() {
                // TODO (wombat, 9/21/12): To change the body of an implemented method, use File | Settings - Editor -  File and Code Templates.
            }
            @Override
            public String sniff() {
                return null;  // TODO (wombat, 9/21/12): To change body of implemented methods use File | Settings - Editor - File and Code Templates.
            }
        

Last modified: 10 August 2022