To achieve this purpose , you should add a custom Live Template:
Open Settings [Ctrl + Alt + S ]
Type "Live Templates" in the Top-Left search bar.
Click the + to add a "Template Group" and type a group name(eg: MyTemplate) to continue
Choose your custom template group(eg: MyTemplate), then click + and choose "Live Template".
I will take "say" for example:
say -> startActivity(new Intent($from$.this,$to$.class));
Type the key that you want to simplify in "Abbreviation" (eg: say),and type the statement in the "Template Text" (eg :startActivity(new Intent($from$.this,$to$.class));)
Click the "define" in the Left-Bottom and choose the situation(eg: Java)