public static <T extends Comparable<T>> T getMaximum(Iterable<T> values) {
T max = null;
for (T value : values) {
if (max == null || max.compareTo(value) < 0) {
max = value;
}
}
return max;
}
Sometimes we want to iterate in reverse order over a list in Java – without (re)sorting the list. Code example:
for (T item : backwards(list)) {
// do something
}
Here is a backwards() method that does this for you (maybe put this code into a util class and use a static import):
public static <T> Iterable<T> backwards(final List<T> list) {
return new Iterable<T>() {
@Override
public Iterator<T> iterator() {
return backwardsIterator(list);
}
};
}
private static <T> Iterator<T> backwardsIterator(List<T> list) {
final ListIterator<T> iter = list.listIterator(list.size());
return new Iterator<T>() {
@Override
public boolean hasNext() {
return iter.hasPrevious();
}
@Override
public T next() {
return iter.previous();
}
@Override
public void remove() {
iter.remove();
}
};
}
Shelr.tv allows Unix/Linux command line users to record something interesting from their terminal and share it to followers.
It is a bit like YouTube for plain text shellcasts. A great feature is that you can copy and paste everything you see.
A nice intro with interesting comments from one of the core developers can be found on linuxaria.com.
A Debian package has been proposed through the Debian “package mentor” system.
Prerequisites:
Save this script as /usr/local/bin/copy-cam-jpgs.sh:
#! /bin/sh
mountpoint=$HOME/devices/camera
targetfolder=$HOME/media/photos
# check availability of cmdline tools
type gphotofs exif fusermount || exit
# mount camera if necessary
if ! mount|grep "$mountpoint"; then
gphotofs "$mountpoint"
fi
cd $mountpoint/*/DCIM/*
for jpg in *.JPG; do
year_month=$(exif --tag=0x9003 -m $jpg \
| cut -f1,2 -d: \
| tr ':' '/')
folder="$targetfolder/$year_month"
mkdir -p "$folder"
mv -v "$jpg" "$folder"
done
cd
fusermount -u $mountpoint
Make it executable like this:
chmod ugo+x /usr/local/bin/copy-cam-jpgs.sh
Then plug in your digital photo camera and run “copy-cam-jpgs.sh“. It will move all JPGs from the camera to $target_folder/yyyy/mm where yyyy is the 4 digit year and mm is the two digit month of the date the photo was taken (as per EXIF data in the JPG).
Put this code into a script section into a common HTML head include file:
$(document).ready(function() {
$('table').each(function() {
var $table = $(this);
var $button = $("<button type='button'>");
$button.text("Export to spreadsheet");
$button.insertAfter($table);
$button.click(function() {
var csv = $table.table2CSV({delivery:'value'});
window.location.href = 'data:text/csv;charset=UTF-8,'
+ encodeURIComponent(csv);
});
});
})
Note:
Sometimes the XFCE desktop icons get messed up, for example by games that temporarily change the screen resolution to 800×600.
A solution to this problem has been mentioned here. It suggests using “sudo chattr +i” to lock the config file where XFCE stores the icon positions.
Alternatively (and without the repeated need for sudo and chattr) you can also backup and restore the ~/.config/xfce4/desktop/icons* file(s) like this:
Create a script /usr/local/bin/save-xfce-desktop-icons.sh like this:
#! /bin/sh mkdir -p ~/.config/xfce4/desktop.bak cp -f ~/.config/xfce4/desktop/icons* ~/.config/xfce4/desktop.bak
Create another script /usr/local/bin/load-xfce-desktop-icons.sh like this:
#! /bin/sh cp -f ~/.config/xfce4/desktop.bak/icons* ~/.config/xfce4/desktop
Make the scripts executable like this
sudo chmod ugo+x /usr/local/bin/save-xfce-desktop-icons.sh sudo chmod ugo+x /usr/local/bin/load-xfce-desktop-icons.sh
Then in the XFCE start menu, go to “Settings” – “Keyboard” – “Application Shortcuts” and configure 2 keyboard shortcuts:
| Command | Shortcut |
|---|---|
| save-xfce-desktop-icons.sh | <Control><ALT>S |
| load-xfce-desktop-icons.sh | <Control><ALT>L |
Then you will be able to backup and restore your icons like this:
The F5 is necessary to synchronize what you see on the screen with the content of ~/.config/xfce4/desktop/icons*.
A simple shell script – let’s call it index-html.sh – to turn a list of file names into html links:
#!/bin/sh echo '<html><body>' sed 's/^.*/<a href="&">&<\/a><br\/>/' echo '</body></html>'
Example use:
ls | index-html.sh > index.html
According to the current TIOBE index, Objective-C market share is growing the fastest. This is the native programming language of Apple devices like iPhone, iPad and iMac.
Absolute volume: Java is still leading the pack (as of 2011/2012).
Relative growth: Look at Scala and Ruby …
Sonatype’s Maven integration for Eclipse (m2e) has been migrated to eclipse.org and is now available from the default update site for Indigo.
This means that you no longer have to add any Sonatype update sites as mentioned on the old (now outdated) m2eclipse site.
In particular, this also means that the old “m2e-extras” update site is obsolete for Eclipse 3.7.x and later. Things like WTP integration or Subclipse integration are now available as “m2e connectors” through Window – Preferences – Maven – Discovery.
All of this is very poorly (or not at all) documented on the new m2e home page and some people had problems with these changes.
Topics I want to cover in the future about Java methods:
