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Only one public class in one file in Java  RSS feed

 
Saishradha Mohanty
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Why can't more than 1 public classes be present in a single JAVA file?
 
Stephan van Hulst
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Because that's just how the designers wanted it to be.

They probably did it to reduce the amount of time that compilers need to find out what file a class description is in.
 
Daniel Cox
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Stephan van Hulst wrote:They probably did it to reduce the amount of time that compilers need to find out what file a class description is in.

The JLS supports your insightful comment

This restriction makes it easy for a Java compiler to find a named class within a package.

For example, the source code for a public type wet.sprocket.Toad would be found in a file Toad.java in the directory wet/sprocket, and the corresponding object code would be found in the file Toad.class in the same directory.
 
Paweł Baczyński
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For example, the source code for a public type wet.sprocket.Toad would be found in a file Toad.java in the directory wet/sprocket, and the corresponding object code would be found in the file Toad.class in the same directory.


Or:
- the source code for a public type wet.sprocket.Toad would be found in a file sprocket.java in the directory wet, and the corresponding object code would be found in the file sprocket$Toad.class in the same directory.
- the source code for a public type wet.sprocket.Toad would be found in a file wet.java in the . directory, and the corresponding object code would be found in the file wet$sprocket$Toad.class in the same directory.

 
Dave Tolls
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And the dev who named their classes either 'wet' or 'sprocket' would be found out on the kerb, holding the contents of their desk in a cardboard box.
;)
 
Paweł Baczyński
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Dave Tolls wrote:And the dev who named their classes either 'wet' or 'sprocket' would be found out on the kerb, holding the contents of their desk in a cardboard box.
;)

The problem is java and javac don't know about this.
 
Campbell Ritchie
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A wet cardboard box, surely.
 
Dave Tolls
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Possibly with some sort of amphibian in it.
 
Campbell Ritchie
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A newt?
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