Can you have two public classes in a single .java file?

No, while defining multiple classes in a single Java file you need to make sure that only one class among them is public. If you have more than one public classes a single file a compile-time error will be generated.

Why can’t we have multiple public classes in a java source file?

There can be only one public class in a java file because the name of java file is same as the name of public class. And obviously we can’t have a file with two different names.

Can a Java file have multiple public classes?

Yes, we can have multiple classes in same java file. So, there is no chance to have two public classes in one file. If we want to access the methods, instances of the other classes we can just make their respective objects in the public file and simply access them.

How do I put two public classes in a package?

If you want to put two public classes in a package, have two java source files containing one public class, but keep the package name same. For example: //save as A. java.

How many classes you can define within a Java package?

There is no limit in the specification, so you can put classes into the package until hitting a technical limitation.

Should Java classes be in separate files?

It is technically legal to have multiple Java top level classes in one file. However this is considered to be bad practice (in most cases), and some Java tools may not work if you do this. The JLS says this: When packages are stored in a file system (§7.2.

How many classes can be defined in a single program in Java?

A single Java program contains two or more classes, it is possible in two ways in Java.

Can we write multiple classes in java?

You can use at most one public class per one java file (COMPILATION UNIT) and unlimited number of separate package-private classes. Compilation unit must named as public class is. You also can have in your public class the unlimited number of inner classes and static nested classes .

Can you have 2 classes in Java?

Yes ! . java file can contain only one public class. If you want these two classes to be public they have to be put into two .

Can We have 2 public classes in same file in Java?

As per the java specification ,2 public class can not be there in same file. To justify the above statement lets have a scenario that tell you why it not possible in java making 2 public class in same file.

How many class files can be in a java file?

There is no restriction on the number of class files in a java file. But we can’t have more than one public class per source code file. Also the name of the file must match the name of the public class.

Why can’t I have multiple classes in a single source-file?

Probably because the java command, since java 11 (see here ), can run also single source-file programs. Imagine you could place two public classes in one file, then think about the work of the compiler: it has to build a .class file from your .java file that represents exactly one class (otherwise the .class ending wouldn’t make any sense).

What if there is no public class in source file?

If there is no public class in the source file then main method can lie in any class and we can give any name to the source file. If you are not following the first constraint then you will receive a compilation error saying “The public type A must be defined in its own file”.