sort by date

developerWorks (IBM)
Focus On Java

sitios en español

developerWorks (IBM)
Copyright 2004 IBM Corporation.
Unit 23: Java in the cloud
Learn the structure, syntax, and programming paradigm of the Java platform and language. Start by mastering the essentials of object-oriented programming on the Java platform, and progress incrementally to the more-sophisticated syntax and libraries that you need to develop complex, real-world Java applications.
Class sharing in Eclipse OpenJ9
Memory footprint and startup time are important performance metrics for a Java virtual machine (JVM). The memory footprint becomes especially important in the cloud environment since you pay for the memory your application uses. This tutorial shows you how to use the shared classes feature in Eclipse OpenJ9 to reduce the memory footprint and improve your JVM startup time.
Get started with Servlet 4.0
Servlet 4.0 fully integrates HTTP/2's server push technology, and also enables runtime discovery of a servlet's mapping URL. With video demonstrations and code examples, this hands-on tutorial gets you started with HTTP/2 server push and the new HttpServletMapping interface in Java servlet and JSF applications.
5 things you didn't know about...: MicroProfile 1.3
Eclipse MicroProfile has just delivered five new APIs for developing Java cloud-native microservices. Get the highlights of what's new in MicroProfile 1.3, with code examples that will have you up and running in no time.
Python Rest API Example — Part 3
Bill Ward08/18/2018 at 05:06:01

With the transition to microservices, it becomes necessary to know how to write simple Rest API's using Python. In this post, I give a python rest API example using Tornado.

This is the third part of this series, where we will code the API endpoints.

Error Handling and std::optional
Bartłomiej Filipek08/18/2018 at 05:05:02

In my last two posts in the C++17 STL series, I covered how to use std::optional. This wrapper type (also called "vocabulary type") is handy when you'd like to express that something is 'nullable' and might be 'empty.' For example, you can return std::nullopt to indicate that the code generated an error... but it this the best choice?

What's the Problem?

Let's see an example:

Understanding the Confusion Matrix
Sunil Kappal08/18/2018 at 05:05:01

The confusion matrix is one of the most popular and widely used performance measurement techniques for classification models. While it is super easy to understand, its terminology can be a bit confusing.

Therefore, keeping the above premise under consideration, this article aims to clear the "fog" around this amazing model evaluation system.

Using GitHub as a Data Lake
Kin Lane08/18/2018 at 05:04:02

There are many situations where we prefer using Amazon S3 as the destination for our date lakes, but increasingly we are also using GitHub as a data lake destination. While GitHub repositories do have some constraints when compared to Amazon S3, when it comes to specific types of big data projects it also has some significant advantages over Amazon S3. Providing us with a solution that can be checked out, forked, and version controlled, helping us stream the data we need across different applications.

Amazon S3 provides us with an industrial grade solution for streaming data in our data lakes. We are developing a growing number of AWS Lambda serverless apps for streaming data from common API sources into an Amazon S3 data lake. However, we are also developing a line of similar functions that stream the same data into GitHub repositories, providing more of a flexible alternative to developing real-time data lakes. Developing approaches to data storage that will allow developers to craft more precise, potentially distributed, and collaborative data lakes.

Avoid Poor Use of Reflection
Language: Java, Expertise: Beginner - Learn more about why it is dangerous to create an instance of a class you don't know.
Validating an URL in Java
Language: Java, Expertise: Intermediate - See an example of an easy way of validating an URL.
Getting All Available Time Zones in Java
Language: Java, Expertise: Intermediate - Learn a quick way to get all of the available time zones in Java.
Avoid Out of Memory Conditions
Language: Java, Expertise: Beginner - Learn why bulk data must never be handled with byte arrays.





Java and Java-based marks are trademarks or registered trademarks of Sun Microsystems, Inc. in the United States and other countries. javasight is independent of Sun Microsystems, Inc.