MemoSoup

NetBeans: use a radio button group

JM — Fri, 30 Jul 2010 14:03:13 +0000

It’s possible to unite several radio buttons into the group. For example, if the buttons “On” and “Off” are in the same button group, only one of them will be active (which is logical).

To create the radio button group in NetBeans do the following:

Use “Button group” from the components palette and put it into Your form. It will be added as “non-visual”

Add the radio buttons to the group, changing their ButtonGroup property (combobox in the Properties)

To remove the radio button group, go to the inspector window and remove radio button group there.

PDF file: set the bookmark

admin — Fri, 09 Jul 2010 12:58:48 +0000

Strange enough, Adobe Acrobar Reader does not allow to put the user-defined bookmarks into the PDF file (and this is so simple and necessary thing!)

However, with the help of some “hack” the bookmarks still could be used.

Here is the trick:

Go to PDF Hacks site and download the zip file with the javascript.
Extract the file bookmark_page.js from the archive
Copy the file bookmark_page.js to one of the following folders:
- %ProgramFiles%\Adobe\Reader\Javascripts
- %AppData%\Adobe\Reader\Javascripts
Please, check the real installation path of the Acrobat software, it could be different on Your system.
Restart the Acrobat Reader

Now You have 4 new menu items in the menu “View”. The first two could be called using shortcut “Alt-V-5″ and “Alt-V-6″ (for English version of Acrobat)

The bookmarks are not saved in the PDF itself, so they could be lost, if the PDF file is moved to some other location.

To uninstall the bookmark script, just remove bookmark_page.js from the Javascripts folder and restart the Acrobat Reader.

Some other PDF tricks could be found in this book:

Linux: get the version of the system

admin — Fri, 18 Jun 2010 15:41:10 +0000

Get the version of the distro:

cat /etc/issue

cat /etc/*-release

Get the kernel version:

uname -r

Perl: get file checksum

admin — Tue, 08 Jun 2010 15:12:23 +0000

use Digest::MD5;
use IO::File;

my $chk = Digest::MD5->new();

foreach my $file (@ARGV)
{
$chk->addfile(IO::File->new($file));

print "$file -> ",$chk->hexdigest,"\n";
}

The additional details could be found on IBM site

Install javadoc for NetBeans

JM — Fri, 14 May 2010 11:51:14 +0000

Java documentation is not included neither in NetBeans installation, nor in “standard” Java SDK installation.

However, it’s possible to download it manually and add to the NetBeans IDE.

Get the Java Documentation (currently “Java SE 6 Documentation”) from Sun site.
Start NetBeans
Select menu item “Tools->Java platforms”, then click “Javadoc” tab
Click “Add Zip/Folder” button and select the path to the downloaded Zip-file

Deactivate social services in Google Reader

admin — Wed, 05 May 2010 13:42:06 +0000

There is a small piece of code (“bookmarklet”), which deactivates social services in Google Reader.

Just go to Google Reader and put into the browser command line the following:

javascript:antisocial('true')

If it’s necessary to reactivate it, use the following:

javascript:antisocial('false')

Java: minimize Application window

admin — Thu, 29 Apr 2010 14:37:36 +0000

The following method could be used to minimize application window, if java.awt.Frame or its subclass is used:

public void setState(int state)
Parameters:
state – Frame.ICONIFIED if this frame is in iconic state;
Frame.NORMAL if this frame is in normal state.

Example:

// Close window on ESC
// use it in the constructor of the window, extending JFrame
//
KeyStroke stroke = KeyStroke.getKeyStroke(KeyEvent.VK_ESCAPE, 0);
rootPane.registerKeyboardAction(new ActionListener() {
public void actionPerformed(ActionEvent e) {
setState(Frame.ICONIFIED);
}
} , stroke, JComponent.WHEN_IN_FOCUSED_WINDOW);

Oracle: eval function

admin — Thu, 11 Feb 2010 13:40:55 +0000

The function takes some expression as the argument and executes it, returning output in the varchar string

CREATE OR REPLACE FUNCTION eval (expr VARCHAR2) RETURN VARCHAR2
AS
ret VARCHAR2(4000);
BEGIN
EXECUTE IMMEDIATE 'begin :result := ' || expr || '; end;' USING OUT ret;
RETURN ret;
END;
/

The discussion and examples could be found there

Oracle: list of the system events

admin — Wed, 10 Feb 2010 16:17:13 +0000

This piece of code show the list of events, set in the Oracle database

SET serveroutput ON
DECLARE
event_level NUMBER;
BEGIN
dbms_output.enable(20000) ;
FOR i IN 10000..33999 LOOP
sys.dbms_system.read_ev(i,event_level);
IF (event_level > 0) THEN
dbms_output.put_line('Event '||to_char(i)||' set at level '||
TO_CHAR(event_level));
END IF;
END LOOP;
END;

Oracle: list of the running transactions

admin — Tue, 09 Feb 2010 12:58:22 +0000

This query shows SID, username and start time of the running transaction.
In addition, number of the used blocks is shown.

SELECT a.sid, a.status, a.username, b.xidusn, b.used_urec, b.used_ublk, b.START_TIME
FROM v$session a, v$transaction b
WHERE a.saddr = b.ses_addr
ORDER BY START_TIME DESC;