On what grounds is he basing that claim?

Java is managed - its dependent on a virtual machine for all interaction with computer hardware (incl. memory management, I/O, audio/visual, GUI, etc). Other managed languages include C#, Python, VB.Net

C++ is unmanaged - it relies on the programmer and 3rd party libraries to deal with hardware interaction and memory management. The same goes for Pascal and C

Whether to use a managed or unmanaged language depends on the kind of application being written. eg, when it comes to high-performance applications (3D games, operating systems, network services, etc), the last thing you need is a virtual machine getting in the way, slowing things down. On the other hand, if the application is strongly GUI-based, (probably designed for end-users), or speed/memory isn't that important, then Java or C# might be a good idea.

Also, for someone learning their first language, it can help to get all the frustrating, fiddly memory management stuff taken care of, so alot of introductory courses will typically start with Java or Python.

So, while the two languages are syntactically similar, and Java's SDK is available in C++, both are used for very different purposes, and can't really be compared.

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