tag:blogger.com,1999:blog-8712770457197348465.post6746939780165215635..comments2024-03-18T23:01:42.768-07:00Comments on Javarevisited: Why Default or No Argument Constructor is Important in Java Class? Answerjavin paulhttp://www.blogger.com/profile/15028902221295732276noreply@blogger.comBlogger6125tag:blogger.com,1999:blog-8712770457197348465.post-34258859752234974852015-04-11T21:39:01.751-07:002015-04-11T21:39:01.751-07:00You should never write a class with a no argument ...You should never write a class with a no argument constructor unless you absolutely must.<br /><br />That implies the object is mutable, and that its dependencies are set on setters.<br /><br />That is an anti pattern (though, all too common).<br /><br />Make classes immutable, use the constructor injection pattern, and your code will be more maintainable, debuggable, <br /><br />No this does notAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-8712770457197348465.post-24415100969504799272014-08-23T05:53:28.944-07:002014-08-23T05:53:28.944-07:00No-argument constructor are evil, it's been pr...No-argument constructor are evil, it's been promoted by Sun on various stage e.g. in Servlet, Reflection and other places, which leads to brittle and hard to test code. With no argument constructor dependencies are hidden, you don't know what a class need to get it's job done, and you only find it after facing problem. Since there is no class, which can work without being independent Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8712770457197348465.post-78561003320189312882014-02-20T20:45:27.336-08:002014-02-20T20:45:27.336-08:00Recently I missed no-argument constructor for a cl...Recently I missed no-argument constructor for a class, which was not final but doesn't implement an interface and don't have a default constructor, because of another parameteric constructor present in the class. Now you can't create mock or dummy version of that class, because <br />a) it doesn't implement an interface<br />b) there is no default constructor, means you can't Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8712770457197348465.post-26808455248448291282014-01-26T05:47:38.597-08:002014-01-26T05:47:38.597-08:00You might like to make a comment about Unsafe.allo...You might like to make a comment about Unsafe.allocateInstance(Class) which doesn't call a constructor.Peter Lawreyhttps://www.blogger.com/profile/10703061328118875566noreply@blogger.comtag:blogger.com,1999:blog-8712770457197348465.post-64586844520218492312014-01-15T16:24:11.810-08:002014-01-15T16:24:11.810-08:00Using an IDE like Eclipse points out to such issue...Using an IDE like Eclipse points out to such issues even before you compile the code. So if you create that parametrized constructor and forget the default constructor, there's Eclipse to come to your rescue!Debjit Sahahttp://gadgetizor.comnoreply@blogger.comtag:blogger.com,1999:blog-8712770457197348465.post-76552866277628759562014-01-15T09:32:16.555-08:002014-01-15T09:32:16.555-08:00How we know, java.lang package is default ? How we know, java.lang package is default ? Venkateswarlu kondahttps://www.blogger.com/profile/10056651302999930511noreply@blogger.com