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Newsgroups: comp.lang.java.programmer
Date: Thu, 28 Feb 2019 11:34:16 -0800 (PST)
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Subject: Re: it's Closeable, but I don't want to close() it yet.
From: Eric Douglas <e.d.programmer@gmail.com>
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Xref: csiph.com comp.lang.java.programmer:38756

On Thursday, February 28, 2019 at 2:10:32 PM UTC-5, Andreas Leitgeb wrote:
> I totally agree for a typical "Pool" scenario.
>=20
> My case can be better characterized in that the Closeable entity is
> an attribute of a Context class, and a getter is called by "users" for
> the ref of the entity.   Lifetime management of the entity is handled
> by the Context.   "Users" (specific methods doing their parts of
> the Context's whole task) really shouldn't close() it or they would
> spoil it for later users.

I did mention if you're pooling it, don't open it.  If you declare a Closea=
ble as a class level variable you can open it once then use it many times w=
ith that instance.  I have a class level java.sql.Connection which I may op=
en in the constructor, but if I put the open call inside a method Eclipse s=
till doesn't complain if it doesn't get closed.  If you only want to open i=
t when the method gets called, initialize it to null.  Then the method can =
say if (conn=3D=3Dnull){conn=3DDriverManager.getConnection(connectstring)}.=
  Remember to synchronize it if the method may be used by multiple threads =
simultaneously.