Simon Willison’s Weblog

Java in the Small (via) Core Java author Cay Horstmann describes how he now uses Java for small programs, effectively taking the place of a scripting language such as Python.

TIL that hello world in Java can now look like this - saved as hello.java:

void main(String[] args) {
    println("Hello world");
}

And then run (using openjdk 23.0.1 on my Mac, installed at some point by Homebrew) like this:

java --enable-preview hello.java

This is so much less unpleasant than the traditional, boiler-plate filled Hello World I grew up with:

public class HelloWorld {
    public static void main(String[] args) {
        System.out.println("Hello, world!");
    }
}

I always hated how many concepts you had to understand just to print out a line of text. Great to see that isn't the case any more with modern Java.

# 18th December 2024, 9:20 pm / java

Queryable Logging with Blacklite (via) Will Sargent describes how he built Blacklite, a Java library for diagnostic logging that writes log events (as zstd compressed JSON objects) to a SQLite database and maintains 5,000 entries in a “live” database while entries beyond that range are cycled out to an archive.db file, which is cycled to archive.timestamp.db when it reaches 500,000 items.

Lots of interesting notes here on using SQLite for high performance logging.

“SQLite databases are also better log files in general. Queries are faster than parsing through flat files, with all the power of SQL. A vacuumed SQLite database is only barely larger than flat file logs. They are as easy to store and transport as flat file logs, but work much better when merging out of order or interleaved data between two logs.”

# 21st August 2023, 6:13 pm / sqlite, logging, zstd, java

Creating Shazam in Java. Using a Fast Fourier Transformation.

# 22nd September 2010, 9:39 pm / algorithms, java, shazam, recovered

ElasticSearch: Your Data, Your Search. A neat example of how ElasticSearch’s schemaless indexes and native JSON support make it ridiculously easy to index different types of data and run queries across them.

# 12th February 2010, 3:22 pm / elasticsearch, java, search, schemaless, json

Elastic Search (via) Solr has competition! Like Solr, Elastic Search provides a RESTful JSON HTTP interface to Lucene. The focus here is on distribution, auto-sharding and high availability. It’s even easier to get started with than Solr, partly due to the focus on providing a schema-less document store, but it’s currently missing out on a bunch of useful Solr features (a web interface and faceting are the two that stand out). The high availability features look particularly interesting. UPDATE: I was incorrect, basic faceted queries are already supported.

# 11th February 2010, 6:33 pm / search, scaling, rest, lucene, java, elasticsearch, json, http, sharding, solr

twitter-text-conformance (via) This is a neat idea: Twitter have released open source libraries for parsing standard tweet syntax in Ruby and Java, but they’ve also released a set of YAML unit tests aimed at anyone who wants to implement the same parsing logic in other languages.

# 6th February 2010, 3:39 pm / twitter, ruby, java, testing, yaml

Plurk: Instant conversations using Comet (via) Plurk’s comet implementation sounds pretty amazing. They’re using a single quad-core server with 32GB of RAM running 8 Node.js instances to serve long-polled comet to 100,000+ simultaneous users. They switched to Node from Java JBoss/Netty and found the new solution used 10 times less memory.

# 1st February 2010, 10:13 am / plurk, comet, javascript, node, netty, java, jboss

Frank Wierzbicki: Leaving Sun. Frank performed miracles at Sun and before, helping bring the Jython project out of stasis and turning it in to an active, community maintained modern Python implementation. If you’re looking for an expert Python/Java/Dynamic languages guy you should snap him up.

# 4th November 2009, 10:33 pm / sun, jython, python, java, frank-wierzbicki

Play framework for Java. I’m genuinely impressed by this—it’s a full stack web framework for Java that actually does feel a lot like Django or Rails. Best feature: code changes are automatically detected and reloaded by the development web server, giving you the same save-and-refresh workflow you get in Django (no need to compile and redeploy to try out your latest changes).

# 25th October 2009, 11:21 pm / play, java, frameworks, web, django, rails

Introducing Cloudera Desktop. It’s a GUI for Hadoop, and under the hood is a whole stack of open source software, including Python, Django, MooTools, Twisted, lxml, CherryPy, Mako, Java and AspectJ.

# 21st October 2009, 6:48 pm / hadoop, open-source, cloudera, python, django, mootools, twisted, lxml, cherrypy, mako, java, aspectj

And so it goes, around again. Charles Miller on Java, pointing out that if you don’t have closures and first-class functions you end up having to add band-aid solutions and special case syntactic sugar. Python’s lack of multi-line lambdas leads to a similar (though less pronounced) effect.

# 3rd September 2009, 9:46 am / java, python, charles-miller, programming-languages

Scriptlets—Quick web scripts (via) From the prolific Jeff Lindsay, a pastebin-style tool for short server-side scripts written in Python, JavaScript or PHP that executes them within a Google App Engine powered sandbox. The Java code that implements the service is available on GitHub.

# 13th August 2009, 1:51 pm / github, jeff-lindsay, webhooks, scriptlets, python, javascript, php, googleappengine, appengine, open-source, java

Jython 2.5.0 Final is out! It’s been a long time coming—congratulations to the team.

# 16th June 2009, 11:21 pm / jython, python, java

Critical Mac OS X Java Vulnerabilities. There’s a five month old Java arbitrary code execution vulnerability which hasn’t yet been patched by Apple. Disable Java applets in your browser until it’s fixed, or random web pages could execute commands on your machine as your user account.

# 19th May 2009, 7:07 pm / osx, security, java, applets, browsers, apple