Item 57 - Use Exceptions only for exceptional conditions

Using exceptions only for exceptional conditions is something we can all agree with. However, this item should have been named "Don't use exceptions for control flow and how to decided between state-testing method and distinguishing return value". Bloch gives an example of how exceptions can be used for ordinary control flow, two alternatives in state-testing method and distinguishing return value and how to choose between them. I was rather hoping for some discussion of what exception conditions are, not just a brief discussion of what they are not.

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Remember to Delegate: The Triangle of Trust

So you think you can lead a team? I’ve been talking and writing a lot about leading a software engineering team in 2025. I started thinking about it more deeply the year before when I decided to give a colleague, who was moving into team leading, some advice: 'Doing the work' isn't the only way to add value Remember to delegate Pick your battles Talk to your team every day Out of this came a talk, “So you think you can lead a team?” which I gave at work, at meetups and at conferences in various different formats during the first quarter of 2025. Here I am looking at Remember to Delegate and an idea which came out of discussion around the talk, The Triangle of Trust, in more detail. Delegate Delegation is a crucial skill for any team lead, yet it is often one of the most challenging aspects of leadership to master. Many leaders, particularly those who have risen through the ranks as individual contributors, struggle to let go of tasks, fearing a loss of control or a dip in ...

Write Your Own Load Balancer: A worked Example

I was out walking with a techie friend of mine I’d not seen for a while and he asked me if I’d written anything recently. I hadn’t, other than an article on data sharing a few months before and I realised I was missing it. Well, not the writing itself, but the end result. In the last few weeks, another friend of mine, John Cricket , has been setting weekly code challenges via linkedin and his new website, https://codingchallenges.fyi/ . They were all quite interesting, but one in particular on writing load balancers appealed, so I thought I’d kill two birds with one stone and write up a worked example. You’ll find my worked example below. The challenge itself is italics and voice is that of John Crickets. The Coding Challenge https://codingchallenges.fyi/challenges/challenge-load-balancer/ Write Your Own Load Balancer This challenge is to build your own application layer load balancer. A load balancer sits in front of a group of servers and routes client requests across all of the serv...

Catalina-Ant for Tomcat 7

I recently upgraded from Tomcat 6 to Tomcat 7 and all of my Ant deployment scripts stopped working. I eventually worked out why and made the necessary changes, but there doesn’t seem to be a complete description of how to use Catalina-Ant for Tomcat 7 on the web so I thought I'd write one. To start with, make sure Tomcat manager is configured for use by Catalina-Ant. Make sure that manager-script is included in the roles for one of the users in TOMCAT_HOME/conf/tomcat-users.xml . For example: <tomcat-users> <user name="admin" password="s3cr£t" roles="manager-gui, manager-script "/> </tomcat-users> Catalina-Ant for Tomcat 6 was encapsulated within a single JAR file. Catalina-Ant for Tomcat 7 requires four JAR files. One from TOMCAT_HOME/bin : tomcat-juli.jar and three from TOMCAT_HOME/lib: catalina-ant.jar tomcat-coyote.jar tomcat-util.jar There are at least three ways of making the JARs available to Ant: Copy the JARs into th...

Paul Grenyer

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