Missing classes in Java Class Library

Java Class Library is an extensive library, but sometimes, it simply misses certain classes or it shows that it was introduced more than two decades ago. While missing functionality, in most cases, can be solved by adding free and open source add-on libraries from the JVM ecosystem, it can both be convenient and a time-saving option if you use a language that has built-in solutions for these problems.

A good example of missing functionality in Java SE version 8's Java Class Library is that it currently has no built-in support for the very commonly used JSON standard. Popular add-on libraries that provide JSON support include Jackson and Google's GSON. Also, modern versions of the Java EE platform provide APIs for JSON support classes. Some languages covered in this book have built-in support for JSON.

Another issue is that some popular classes from Java Class Library require a lot of boilerplate code to use them effectively. Languages, such as Groovy, add wrappers to many popular Java Class Library classes that make these APIs much easier to use.