JDK 15: The New Features In Java 15
Removes the Nashorn JavaScript script engine, the APIs and the jjs tool as mentioned below as it was already deprecated in java 11. jdk.scripting.nashorn : It contains the jdk.nashorn.api.scripting and jdk.nashorn.api.tree packages.
jdk.scripting.nashorn.shell : It contains the jjs tool.
JDK 15: The new features in Java 15
Quick glance on earlier Java Versions Features : Java 14 Features - JDK 14 Java 14 (Java SE 14) and its Java Development Kit 14 (JDK 14) open-source has been released on 17 March 2020, the most common coding language and application platform in the world. A significant number of Java Enhancement Proposals (JEPs) have been released in version 14. (Even more JEPs than Java 12 and 13 combined) JAVA 14 addresses a total of 16 main enhancements/changes (JEPs) ranging from the Java language support to the latest APIs for ongoing JDK flight recorder monitoring. The entire feature list consists of: Pattern Matching for instanceof
Non-Volatile Mapped Byte Buffers
Helpful NullPointerExceptions
Switch Expressions (Standard)
Packaging Tool (Incubator)
NUMA-Aware Memory Allocation for G1
JFR Event Streaming
Records (Preview)
Deprecate the Solaris and SPARC Ports
Remove the Concurrent Mark Sweep (CMS) Garbage Collector
ZGC on macOS
ZGC on Windows
Deprecate the ParallelScavenge + SerialOld GC Combination
Remove the Pack200 Tools and API
Text Blocks (Second Preview)
Foreign-Memory Access API
Java 13 Features - JDK 13 Dynamic CDS Archives
ZGC: Uncommit Unused Memory
Reimplement the Legacy Socket API
Switch Expressions (Preview)
Text Blocks (Preview)
Java 12 Features Shenandoah: A Low-Pause-Time Garbage Collector (Experimental)
Microbenchmark Suite
Switch Expressions (Preview)
JVM Constants API
One AArch64 Port, Not Two
Default CDS Archives
Abortable Mixed Collections
Promptly Return Unused Committed Memory from G1
Java 11 Features 181: Nest-Based Access Control
309: Dynamic Class-File Constants
315: Improve Aarch64 Intrinsics
318: Epsilon: A No-Op Garbage Collector
320: Remove the Java EE and CORBA Modules
321: HTTP Client (Standard)
323: Local-Variable Syntax for Lambda Parameters
324: Key Agreement with Curve25519 and Curve448
327: Unicode 10
328: Flight Recorder
329: ChaCha20 and Poly1305 Cryptographic Algorithms
330: Launch Single-File Source-Code Programs
331: Low-Overhead Heap Profiling
332: Transport Layer Security (TLS) 1.3
333: ZGC: A Scalable Low-Latency Garbage Collector(Experimental)
335: Deprecate the Nashorn JavaScript Engine
336: Deprecate the Pack200 Tools and API
Java 10 Features Local-variable type inference
Experimental Java-based JIT compiler.This is the integration of the Graal dynamic compiler for the Linux x64 platform
Application class-data sharing. This allows application classes to be placed in the shared archive to reduce startup and footprint for Java applications
Time-based release versioning
Parallel full GC
Garbage-collector interface
Additional Unicode language-tag extensions
Root certificates
Thread-local handshakes
Heap allocation on alternative memory devices
Remove the native-header generation tool - javah
Consolidate the JDK forest into a single repository
Java 9 Features Modularization of the JDK under Project Jigsaw (Java Platform Module System)
jshell: The Java Shell (a Java REPL)
Ahead-of-time compilation
XML catalogs
More concurrency updates. It includes a Java implementation of Reactive Streams, including a new Flow class that included the interfaces previously provided by Reactive Streams
Variable handles: define a standard means to invoke the equivalents of various java.util.concurrent.atomic and sun.misc.Unsafe operations
jlink: The Java Linker: create a tool that can assemble and optimize a set of modules and their dependencies into a custom run-time image. It effectively allows to produce a fully usable executable including the JVM to run it
JavaDB was removed from JDK
HiDPI graphics: automatic scaling and sizing
Java 8 Features Language-level support for lambda expressions and default methods (virtual extension methods) which allow the addition of methods to interfaces without breaking existing implementations.
Project Nashorn, a JavaScript runtime which allows developers to embed JavaScript code within applications
Annotation on Java types
Unsigned integer arithmetic
Repeating annotations
Date and time API
Statically-linked JNI libraries
Launch JavaFX applications (direct launching of JavaFX application JARs)
Remove the permanent generation
Java 7 Features JVM support for dynamic languages
Compressed 64-bit pointers
Strings in switch
Automatic resource management in try-statement
Improved type inference for generic instance creation, aka the diamond operator
Simplified varargs method declaration
Binary integer literals
Allowing underscores in numeric literals
Catching multiple exception types and rethrowing exceptions with improved type checking
Concurrency utilities
New file I/O library adding support for multiple file systems
Timsort is used to sort collections and arrays of objects instead of merge sort
Library-level support for elliptic curve cryptography algorithms
An XRender pipeline for Java 2D, which improves handling of features specific to modern GPUs
New platform APIs for the graphics features
Enhanced library-level support for new network protocols, including SCTP and Sockets Direct Protocol
Upstream updates to XML and Unicode
Java deployment rule sets
Java 6 Features Support for older Win9x versions dropped
Scripting Language Support
Dramatic performance improvements for the core platform, and Swing.
Improved Web Service support through JAX-WS.
JDBC 4.0 support.
Java Compiler API
Upgrade of JAXB to version 2.0
Support for pluggable annotations
Many GUI improvements, such as integration of SwingWorker in the API, table sorting and filtering, and true Swing double-buffering (eliminating the gray-area effect).
JVM improvements include: synchronization and compiler performance optimizations, new algorithms and upgrades to existing garbage collection algorithms, and application start-up performance.
Java 6 can be installed to Mac OS X 10.5 (Leopard) running on 64-bit (Core 2 Duo and higher) processor machines.[54] Java 6 is also supported by both 32-bit and 64-bit machines running Mac OS X 10.6
Java 5 Features Generic
Metadata
Autoboxing/unboxing
Enumerations
Varargs
Enhanced for each loop
Improved
Static imports
Improvements - Semantics of execution for multi-threaded Java programs
Improvements - Automatic stub generation for RMI objects
Improvements - Swing: New skinnable look and feel, called synth
Improvements - The concurrency utilities in package java.util.concurrent
Improvements - Scanner class for parsing data from various input streams and buffers
Michael Rasmussen is a product manager for JRebel by Perforce, previously having worked more than 10 years on the core technology behind JRebel. Michael is a true geek at heart. His professional interests include everything Java, as well as other languages and technologies for the JVM, including an unhealthy obsession with java bytecode.
If you implement your own accessor methods, then ensure that they have the same characteristics as implicitly derived accessors (for example, they're declared public and have the same return type as the corresponding record class component). Similarly, if you implement your own versions of the equals, hashCode, and toString methods, then ensure that they have the same characteristics and behavior as those in the java.lang.Record class, which is the common superclass of all record classes.
You might get a compiler error if your source file imports a class named Record from a package other than java.lang. A Java source file automatically imports all the types in the java.lang package though an implicit import java.lang.*; statement. This includes the java.lang.Record class, regardless of whether preview features are enabled or disabled.
Both Record in the com.myapp package and Record in the java.lang package are imported with a wildcard. Consequently, neither class takes precedence, and the compiler generates an error when it encounters the use of the simple name Record.
To compile source code with javac that uses preview features from JDK release n, use javac from JDK release n with the --enable-preview command-line option in conjunction with either the --release n or -source n command-line option.
To run an application that uses preview features from JDK release n, use java from JDK release n with the --enable-preview option. To continue the previous example, to run MyApp, run java from JDK 12 as follows:
JDK 15 features released on 15th Sept, 2020. After 25 years of innovation, Java continues to be the #1 programming language, used by over 69 percent of full-time developers worldwide. The latest Java Development Kit (JDK) delivers new functionalities to improve developer productivity & security. As a developer, we should have knowledge of the features of new release, at least which may be important to our development part. JDK 15 features also may have an important role in the java technical interview process. Not only JDK 15, but features of other previous versions also can play an important role in the interview. 041b061a72