The modular framework is trending on the Java platform. From Java 9, the Java platform became modular, and that helps to remove the flaws in encapsulation.

There are certain problems resulted to have modularity support, as explained here:

• Java platform size: Since the last couple of decades, there was no need to add modularity support in Java. But there are many new lightweight platforms available on the market, like the Internet of Things (IoT), and Node.js. So, it was an urgent need to reduce the size of JDK version, because initial versions of JDK were less than 10 MB in size, whereas recent versions need more than 200 MB.
• ClassLoader difficulty: When the Java ClassLoader searches for the classes, it will pick the class definition that is around itself, and immediately load the first class available. So, if there is the same class available in different JARs, then it is not possible for ClassLoader to specify the JAR from which the class is to be loaded.

To make Java applications modular, Open System Gateway initiative (OSGi) is one of the initiatives to bring modularity into the Java platform. In OSGi, each module is denoted as a bundle. Each bundle has its own life cycle, with different states as installed, started, and stopped. 

The Jigsaw project is a primary motivation under the Java Community Process (JCP), to bring modularity into Java. Its main purpose is to define and implement a modular structure for JDK and to define a module system for Java applications.