What is a marker interface in Java?

What is a marker interface in Java?

A marker interface is an interface that has no methods or constants inside it. It provides run-time type information about objects, so the compiler and JVM have additional information about the object. A marker interface is also called a tagging interface.

What is marker interface in Java explain with example?

An empty interface in Java is known as a marker interface i.e. it does not contain any methods or fields by implementing these interfaces a class will exhibit a special behavior with respect to the interface implemented. java. Cloneable and java. io. Serializable are examples of marker interfaces.

Where do we use marker interface in Java?

Marker interface is used as a tag to inform a message to the Java compiler so that it can add special behaviour to the class implementing it. Java marker interface has no members in it.

Can we create a marker interface in Java?

You can create your own custom marker interface in Java. Here is an example using custom Marker interface in Java. As we know marker interfaces define a type, that can be used with instanceof operator to test whether object is an instance of the specified type.

Why are marker interface used?

Marker interface is used as a tag that inform the Java compiler by a message so that it can add some special behavior to the class implementing it. Implementing an empty interface tells the compiler to do some operations. It is used to logically divide the code and a good way to categorize code.

Why is marker interface empty?

Marker interface is an empty interface where in doesn’t have any fields or methods in it. It is used to give some kind of command to jvm or a compiler. Example are Serializable, Clonnable etc.. When we implement empty interface, it tells compiler to do some operations.

Why do we use marker interface?

What is marker annotation in Java?

What is a Marker Annotation? Marker annotations are special annotations in Java that do not contain any members or data. As marker interfaces do not contain any members, just declaring the annotation in your code is sufficient for it to influence the output in whatever terms you want.

What is the purpose of markers?

General purpose They are used for writing on metals, plastics, ceramics, wood, stone, cardboard etc. However, the mark made by them is semi-permanent on some surfaces. Most permanent marker ink can be erased from some plastic surfaces (like polypropylene and teflon) with little rubbing pressure.

What is the use of marker?

A marker is an ink-filled pen with a wide tip. Kids often use washable markers, while adults are usually trusted with the permanent type. Permanent markers contain ink that can’t be washed away, and they’re useful for labeling and marking things like cardboard boxes and file folders.

Can we write marker interface?

Can we create custom marker interface? Of course you can write a marker interface. A marker interface is generally just a Interface with no methods at all (so any class could implement it).

Why do we create marker interface in Java?