Articles

There are a good number of articles that articulate functional differences between HashMap, Hashtable, and ConcurrentHashMap. This post compares the performance behavior of these data structures through practical examples. If you don’t have the patience to read the entire post, here is the bottom line: when you are confronted with the decision of whether to use HashMap, Hashtable, or ConcurrentHashMap, consider using ConcurrentHashMap since it’s thread-safe implementation without compromise in performance.

Performance Study

 To study the performance characteristics, I have put together this sample program:

Source de l’article sur DZONE

‘java.lang.System.getProperty()’ is a common API used by Java developers to read the System properties that are configured during application startup time. i.e. when you pass “-DappName=buggyApp” as your application’s startup JVM argument, the value of the ‘appName’ system property can be read by invoking the ‘java.lang.System.getProperty()’. Example:

Java

 

public static String getAppName() { String app = System.getProperty("appName");   return app;
}

Source de l’article sur DZONE