What is new in Java

JavaSE 11 Features

• Coming soon....

JavaSE 10 Features

• Local Variable Type Inference
• Time-Based Release Versioning
• Garbage-Collector Interface
• Parallel Full GC for G1
• Heap Allocation on Alternative Memory Device
• Consolidate the JDk Forest Into a Single Repository
• Root Certificates
• Experimental Java-Based JIT Compiler
• Thread-Local Handshakes
• Remove the Native-Header Generation Tool

https://dzone.com/articles/java-10-released-10-new-features-devs-should-know

JavaSE 9 Features

• The Java platform Module system 
• Linking
• JShell: the interactive Java REPL
• Improved Javadoc
• Collection Factory Methods
• Stream API Improvements
• Private Interface Method
• HTTP/2
• Multi Release JARs

https://www.pluralsight.com/blog/software-development/java-9-new-features

JavaSE 8 Features

The important features of JavaSE 8 are lambda expressions, methods references, default methods, functional interface, java 8 date/time, stream classes etc.

• Java 8 Date/Time API (Java 8)
• Lambda Expressions (Java 8)
• Method References (Java 8)
• Functional Interfaces (Java 8)
• Stream (Java 8)
• Base64 Encode Decode (Java 8)
• Default Methods (Java 8)
• forEach method(Java 8)
• Collectors(Java 8)
• StringJoiner(Java 8)
• Optional class (Java 8)
• Nashorn JavaScript (Java 8)
• Parallel Array Sorting (Java 8)
• Type Inference (Java 8)
• Method Parameter Reflection (Java 8)
• Type annotations and repeating annotations (Java 8)
• Java JDBC Improvements (Java 8)
• Java IO Improvement (Java 8)
• Java Concurrency Improvement (Java 8)

https://www.javatpoint.com/New-features-in-java

JavaSE 7 Features

The important features of JavaSE 7 are try with resource, catching multiple exceptions etc.

• String in switch statement (Java 7)
• Binary Literals (Java 7)
• The try-with-resources (Java 7)
• Caching Multiple Exceptions by single catch (Java 7)
• Underscores in Numeric Literals (Java 7)

JavaSE 6 Features

The important feature of JavaSE 6 is premain method (also known as instrumentation).

• Instrumentation (premain method) (Java 6)

J2SE 5 Features

The important features of J2SE 5 are generics and assertions. Others are auto-boxing, enum, var-args, static import, for-each loop (enhanced for loop etc.

• For-each loop (Java 5)
• Varargs (Java 5)
• Static Import (Java 5)
• Autoboxing and Unboxing (Java 5)
• Enum (Java 5)
• Covariant Return Type (Java 5)
• Annotation (Java 5)
• Generics (Java 5)

J2SE 4 Features

The important feature of J2SE 4 is assertions. It is used for testing.

• Assertion (Java 4)