Interface just means "public API" of something: That is the contract against which you write software. Java uses the keyword
interface to define classes without code that contain such contracts.
The bridge pattern is a design pattern. It stands for decoupling. You could say Java interfaces are one way to implement this pattern.
Note that bridges usually expose the full API while Java interfaces can expose only part of the API. Example: You have a class
Foo with two methods:
A bridge is anything which has the same public API as
Foo and which can be used in any place where
Foo can be used.
With interfaces, you can have two. One contains
bar() and the other
baz(). Any class which implements both is a valid implementation for
Foo but you can also have classes which implement only one of them.