Polymorphism vs Strategy pattern

Question

What is the difference between the Strategy pattern and Polymorphism in Java?

I\'m confused that whatever is achieved via Strategy Pattern is

Answer 1

Consider this

we have animals and a strategy pattern object to describe how they move... for instance

fly/swim/walk

Given the large number of animals that use any of these methods (ie thousands of different animals fly), we need to use the same code for many different animals. That code should only exist in one place, so that it is easily changed and doesn't take up any unneeded space.

In this example, a straightforward polymorphism approach will result in massive code duplication. A more complex approach which places a intermediate class between animal and say robin fail to take in to consideration that how a animal moves is not really what defines it. Furthermore, it is possible that a animal has other strategy objects and they cannot all be made polymorphic through intermediate classes.