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Summary In constructors in the Java programming language, allow statements that do not reference the instance being created to appear before an explicit constructor invocation. This is a preview language feature. Goals Give developers greater freedom to express the behavior of constructors, enabling the more natural placement of logic that currently must be factored into auxiliary static methods,

Summary Introduce virtual threads to the Java Platform. Virtual threads are lightweight threads that dramatically reduce the effort of writing, maintaining, and observing high-throughput concurrent applications. This is a preview API. Goals Enable server applications written in the simple thread-per-request style to scale with near-optimal hardware utilization. Enable existing code that uses the j

JEPs in JDK 17 integrated since JDK 11 Here are all of the JEPs integrated since the previous long-term-support (LTS) release, JDK 11. Incubator and Preview JEPs that were superseded by later JEPs in JDKs 12 through 17 are not included. The release in which a JEP was integrated is shown in parentheses after the JEP’s title. Additions

Summary Introduce an API that offers statically-typed, pure-Java access to native code. This API, together with the Foreign-Memory API (JEP 393), will considerably simplify the otherwise error-prone process of binding to a native library. History The Foreign-Memory Access API, which provides the foundations for this JEP, was first proposed by JEP 370 and targeted to Java 14 in late 2019 as an incu

Summary Add Unix-domain (AF_UNIX) socket support to the socket channel and server-socket channel APIs in the java.nio.channels package. Extend the inherited channel mechanism to support Unix-domain socket channels and server socket channels. Goals Unix-domain sockets are used for inter-process communication (IPC) on the same host. They are similar to TCP/IP sockets in most respects, except that th

We publish fixes to vulnerabilities in OpenJDK source code four times per year, in January, April, July, and October, on the Tuesday closest to the seventeenth of the month. We post advisories describing the severity, area, and affected versions of each fix to the vuln-announce mailing list, signed with the advisory key for integrity. We encourage you to update to the latest version of your prefer

Summary Improve the usability of NullPointerExceptions generated by the JVM by describing precisely which variable was null. Goals Offer helpful information to developers and support staff about the premature termination of a program. Improve program understanding by more clearly associating a dynamic exception with static program code. Reduce the confusion and concern that new developers often ha

DRAFT DRAFT DRAFT Summary Extend the space of JVM type descriptors to include type operators, which are symbolic references to factory-made types. This is a separable component of template classes. Goals Allow JVM type descriptors (for methods, fields, and constants) to make new distinctions between types not already present in the system of classes, primitives, and arrays. Support future translat

JDK 11 is the open-source reference implementation of version 11 of the Java SE Platform as specified by by JSR 384 in the Java Community Process. JDK 11 reached General Availability on 25 September 2018. Production-ready binaries under the GPL are available from Oracle; binaries from other vendors will follow shortly. The features and schedule of this release were proposed and tracked via the JEP

Summary Deprecate the Nashorn JavaScript script engine and APIs, and the jjs tool, with the intent to remove them in a future release. Motivation The Nashorn JavaScript engine was first incorporated into JDK 8 via JEP 174 as a replacement for the Rhino scripting engine. When it was released, it was a complete implementation of the ECMAScript-262 5.1 standard. With the rapid pace at which ECMAScrip

Summary Enhance the java launcher to run a program supplied as a single file of Java source code, including usage from within a script by means of "shebang" files and related techniques. Non-Goals It is not a goal to change either the Java Language Specification (JLS) or javac to accommodate shebang files. Likewise, it is not a goal to evolve the Java language into a general purpose scripting lang

Introduction Java SE 10 introduced type inference for local variables. Previously, all local variable declarations required an explicit (manifest) type on the left-hand side. With type inference, the explicit type can be replaced by the reserved type name var for local variable declarations that have initializers. The type of the variable is inferred from the type of the initializer. There is a ce

Alan Bateman, Alex Buckley, Dalibor Topic, Iris Clark, John Rose Summary Revise the version-string scheme of the Java SE Platform and the JDK, and related versioning information, for present and future time-based release models. Goals Recast the version-number scheme introduced by JEP 223 so that it better fits time-based release models that define feature releases, which can contain new features,

Summary Enhance the Java programming language with pattern matching for the instanceof operator. Pattern matching allows common logic in a program, namely the conditional extraction of components from objects, to be expressed more concisely and safely. This is a preview language feature in JDK 14. Motivation Nearly every program includes some sort of logic that combines testing if an expression ha

Summary Enhance the expressiveness of the enum construct in the Java Language by allowing type-variables in enums (generic enums), and performing sharper type-checking for enum constants. Goals These two enhancements work together to enable enum constants to carry constant-specific type information as well as constant-specific state and behavior. There are many situations where developers have to

Summary Compile Java classes to native code prior to launching the virtual machine. Goals Improve the start-up time of both small and large Java applications, with at most a limited impact on peak performance. Change the end user's work flow as little as possible. Non-Goals It is not necessary to provide an explicit, exposed library-like mechanism for saving and loading compiled code. Motivation J

Summary Enhance the Java Language to extend type inference to declarations of local variables with initializers. Goals We seek to improve the developer experience by reducing the ceremony associated with writing Java code, while maintaining Java's commitment to static type safety, by allowing developers to elide the often-unnecessary manifest declaration of local variable types. This feature would

Graal Project a quest for the JVM to leverage its own J Mission The Graal OpenJDK project grew out of the Maxine VM project. In the context of the Maxine VM, Graal demonstrated that a compiler written in Java (with all its software engineering advantages) could generate highly optimized code without compromising on compile times. Graal was then spun off as an OpenJDK project in 2012 to bring these

Summary Adopt a more space-efficient internal representation for strings. Goals Improve the space efficiency of the String class and related classes while maintaining performance in most scenarios and preserving full compatibility for all related Java and native interfaces. Non-Goals It is not a goal to use alternate encodings such as UTF-8 in the internal representation of strings. A subsequent J

Project Jigsaw: Module System Quick-Start Guide This document provides a few simple examples to get developers started with modules. The file paths in the examples use forward slashes, and the path separators are colons. Developers on Microsoft Windows should use file paths with back slashes and a semi-colon as the path separator. Greetings Greetings world Multi-module compilation Packaging Missin

Summary Reimplement GC logging using the unified JVM logging framework introduced in JEP 158. Non-Goals It is not a goal to ensure that current GC log parsers work without change on the new GC logs. Not all log entries will necessarily be reproduced in the new logging format. Description Reimplement GC logging in a manner that is as consistent as is reasonable with the current GC logging format. T

This is the second edition of this document. Relative to the initial edition this edition introduces material on compatibility and migration, revises the description of reflective readability, reorders the text to improve the flow of the narrative, and is organized into a two-level hierarchy of sections and subsections for easier navigation. There are still many open issues in the design, the reso

Summary Define an efficient standard API for stack walking that allows easy filtering of, and lazy access to, the information in stack traces. Non-Goal It is not a goal to convert all existing stack walking code in the JDK to use this new API. Motivation There is no standard API to traverse selected frames on the execution stack efficiently and access the Class instance of each frame. There are ex

Summary Define a standard means to invoke the equivalents of various java.util.concurrent.atomic and sun.misc.Unsafe operations upon object fields and array elements, a standard set of fence operations for fine-grained control of memory ordering, and a standard reachability-fence operation to ensure that a referenced object remains strongly reachable. Goals The following are required goals: Safety

Summary Enhance the javadoc tool to generate HTML5 markup. Goals Provide an option to the standard doclet to request either HTML 4 or HTML5 output. The HTML5 markup is semantic, i.e., clearly separating meaning from style and content. The parts of the pages generated by the standard doclet using HTML5 markup satisfy accessibility requirements. Non-Goals It is a not a goal to replace the current th

Summary Develop a Java based JVM compiler interface (JVMCI) enabling a compiler written in Java to be used by the JVM as a dynamic compiler. Goals Allow a Java component programmed against the JVMCI to be loaded at runtime and used by the JVM’s compile broker. Allow a Java component programmed against the JVMCI to be loaded at runtime and used by trusted Java code to install machine code in the JV

Alan Bateman, Brian Goetz, Paul Sandoz, Steve Drach Summary Extend the JAR file format to allow multiple, Java-release-specific versions of class files to coexist in a single archive. Goals Enhance the Java Archive Tool (jar) so that it can create multi-release JAR files. Implement multi-release JAR files in the JRE, including support in the standard class loaders and JarFile API. Enhance other cr

The goal of this Project was to produce an open-source reference implementation of the Java SE 9 Platform as defined by JSR 379 in the Java Community Process. JDK 9 reached General Availability on 21 September 2017. Production-ready binaries under the GPL are available from Oracle; binaries from other vendors will follow shortly. The features and schedule of this release were proposed and tracked