Features

  1. Simple
  2. Multithreaded
  3. Support TCP/IP
  4. Secured
  5. Portable
  6. Platform Independent
  7. High performance
  8. Distributed
  9. Robust
  10. Object oriented programming

Simple
Java is designed to be easy to learn. If you understand the basic concept of OOP Java, it would be easy to master.

Java is very easy to learn. It inherits many features from C, C++ and removes complex features like pointers, operator overloading, multiple inheritance, explicit memory allocation etc

Multithreaded
With Java's multithreaded feature it is possible to write programs that can perform many tasks simultaneously. This design feature allows the developers to construct interactive applications that can run smoothly.

A multi-threaded program contains two or more parts that can run concurrently and each part can handle a different task at the same time making optimal use of the available resources specially when your computer has multiple CPUs.

By definition, multitasking is when multiple processes share common processing resources such as a CPU. Multithreading extends the idea of multitasking into applications where you can subdivide specific operations within a single application into individual threads. Each of the threads can run in parallel. The OS divides processing time not only among different applications, but also among each thread within an application.

Secured
With Java's secure feature it enables to develop virus-free, tamper-free systems. Authentication techniques are based on public-key encryption.

Java is by design highly secure as it is not asking developers to interact with underlying system memory or operation system. Bytecode is secure and several security flaws like buffer overflow, memory leak are very rare. Java exception handling mechanism allows developers to handle almost all type of error/exceptions which can happen during program execution. Automatic garbage collection helps in maintaining the system memory space utilization in check.

Portable
Being architecture-neutral and having no implementation dependent aspects of the specification makes Java portable. Compiler in Java is written in ANSI C with a clean portability boundary, which is a POSIX subset.

Due to this portability, java was an instant hit since inception. It was particulary useful for internet based application where platforms varied from place to place and same code base can be used across multiple platform. So collaboration between developers was easy across multiple locations.

Robust
Java makes an effort to eliminate error prone situations by emphasizing mainly on compile time error checking and runtime checking. Automatic garbage collection, strong memory management, no pointers, no direct access to system memory, exception handling, error handling are some of the key features which makes Java a Robust, strong language to rely on.

High performance
With the use of Just-In-Time compilers, Java enables high performance. JVM uses JIT compiler to improves the execution time of the program. Below are some general optimizations that are done by the JIT compilers

1. Method inlining
2. Dead code elimination
3. Heuristics for optimizing call sites
4. Constant folding

Reference link
https://www.tutorialspoint.com/java/java-features.htm