Tag: programming

HTTP: The importance of declaring non-cachable resources as such

It works fine with Chrome and it fails on an Android 2.3 browser - the page is performing an XmlHttpRequest to the server for a resource that just changed for sure and yet it gets back an older version. That's the result of a. the browser assuming a resource is cachable even if no Etag … Continue reading HTTP: The importance of declaring non-cachable resources as such →

CRTL + Left click on java methods/members/classes slow in Eclipse

In a certain, corporate installation of Eclipse on a quite fast computer CRTL+Left click on java classes, members and methods in the java editor incurred always several seconds of a locked up eclipse which coincided with moderate network traffic. When disconnecting the network the delay would magically vanish. Pierre-Antoine Grégoire came up with the reason … Continue reading CRTL + Left click on java methods/members/classes slow in Eclipse →

Solving the 8 Queens puzzle with bit operations

The 8 queens puzzle is a classic (and quite fun to solve) toy problem: place eight queens on a chess board in such a way that all queens could fully move without being obstructed by any other queen. While without practical applications, it illustrates a number of aspects of designing algorithms and implementing programmes: - … Continue reading Solving the 8 Queens puzzle with bit operations →

The jsp-file directive

The jsp-file directive in web.xml allows mapping of JSPs to concrete URLs: <servlet> <servlet-name>My Hidden Page</servlet-name> <jsp-file>/mydir/foo.jsp</jsp-file> </servlet> <servlet-mapping> <servlet-name>My Hidden Page</servlet-name> <url-pattern>/hidden</url-pattern> </servlet-mapping> Shame on me, I didn't know about this. As seen here: http://mail-archives.apache.org/mod_mbox/tomcat-users/200107.mbox/%3CPine.BSF.4.21.0107271807540.7976-100000@localhost%3E