java - When should a jar file name have a version number in it? What are the pros and cons of this? -

i'm new java. when @ jar files, see mix of including version in file name , not.

• under circumstances either of these idea?
• what pros , cons of putting version number in jar file name?
• if version in jar file name, client jars need recompiled make use of it?

i've looked around information, i've found prescriptive direction, rather thoughtful explanation. this link little bit helpful, these two questions aren't really.

1. versioned jar-files idea
2. the version visible & can spot conflicts. can't see substantial* con.
3. no, name of jar-files matters if have conflicting class files in 2 or more jar-files**.

_{*: e.g., insignificat cons, such executable jars might easier type without version numbering}

_{**: e.g., if have class com.foo.bar in 2 jar-files, classloader load either one, typically depending on finds first. same applies if have 2 versions of same jar - typically not know version used.}