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JDK's Bug?! java.util.Properties don't save comments!
Joined: Feb 17, 2003
Jul 19, 2006 00:52:00
I want to edit a test.properties file using class
. My file is:
#my comment here test1=www.li.com #my comment 2 here test2=www.liren.com #my comment 3 here test3=www.lyo.com
After I run my application,all the comment is lost!
My code is:
InputStream in=....... Properties p=new Properties(); p.load(in); p.setProperty("test","hi"); p.store(new FileOutputStream("test.properties"),"changed");
After I run my code,the test.properties change to this:
#changed test1=www.li.com test2=www.liren.com test3=www.lyo.com
Where is my comments!? They are deleted by
All my comments information lost! why Properties class don't save comment? ;-(
When I face C# and Java I choose Java.
Jesper de Jong
Joined: Aug 16, 2005
Jul 19, 2006 01:08:00
The specifications of the Properties class and the load(...) and store(...) methods do not say anything about preserving your comments in the file.
This is not a JDK bug - the Properties class was just not designed to save files with comments etc. in exactly the same format as what you typed in by hand.
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Joined: Nov 24, 2005
Jul 19, 2006 01:11:00
I agree with Jesper.
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Joined: Mar 22, 2005
Jul 19, 2006 01:52:00
If you absolutely need to preserve comments when programmatically modifying properties files, have a look at the
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subject: JDK's Bug?! java.util.Properties don't save comments!
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