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Java 20 Is Out!
This release is the Reference Implementation of version 20 of the Java SE Platform, as specified by JSR 395 in the Java Community Process.
OpenJDK
Learn about the key active Projects in the Community including Amber (high-productivity language features), Babylon (foreign programming models), Leyden (better startup and warmup), Loom (lightweight concurrency), Panama (foreign functions and foreign data), Valhalla (primitive types and specialized generics), and, of…
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JEP draft: No longer require super() and this() to appear first in a constructor
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 .
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JEP draft: Prepare to make final mean final
Issue warnings about uses of deep reflection to mutate final fields. These warnings aim to prepare developers for a future release that ensures integrity by default by restricting final field mutation, which will make Java programs safer and potentially faster. Application developers can avoid both current warnings…
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JEP 450: Compact Object Headers
Reduce the size of object headers in the HotSpot JVM from between 96 and 128 bits down to 64 bits on 64-bit architectures. This will reduce heap size, improve deployment density, and increase data locality.
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JEP 430: String Templates (Preview) Proposed to Target Java 21
Enhance the Java programming language with string templates . String templates complement Java's existing string literals and text blocks by coupling literal text with embedded expressions and template processors to produce specialized results. This is a preview language feature and API .
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Paving the on-ramp to Java
Java is one of the most widely taught programming languages in the world. Tens of thousands of educators find that the imperative core of the language combined with a straightforward standard library is a foundation that students can comfortably learn on. Choosing Java gives educators many degrees of freedom: they can…
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JEP 467: Markdown Documentation Comments
Enable JavaDoc documentation comments to be written in Markdown rather than solely in a mixture of HTML and JavaDoc @ -tags.
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JEP 483: Ahead-of-Time Class Loading and Linking
Improve startup time by making the classes of an application instantly available, in a loaded and linked state, when the HotSpot Java Virtual Machine starts. Achieve this by monitoring the application during one run and storing the loaded and linked forms of all classes in a cache for use in subsequent runs. Lay a…
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Java 21: First Release Candidate
This release is the Reference Implementation of version 21 of the Java SE Platform, as specified by JSR 396 in the Java Community Process.
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JEP 431: Sequenced Collections
Introduce new interfaces to represent collections with a defined encounter order. Each such collection has a well-defined first element, second element, and so forth, up to the last element. It also provides uniform APIs for accessing its first and last elements, and for processing its elements in reverse order.
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JDK 28
This release will be the Reference Implementation of version 28 of the Java SE Platform, as specified by JSR 403 in the Java Community Process.
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Code Models
Code reflection, an enhancement to Java reflection, enables access to symbolic representations of Java code in method and lambda expressions. “Symbolic representations of Java code” may seem like a fancy term, but its easily demystified. It’s a model of Java code where the code of a method or lambda expressions is…
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JEP draft: Exception handling in switch
Enhance the switch construct so that exceptions thrown by the selector (the e in switch (e) ... ) can be handled in the switch block. Alongside a previous enhancement to handle null selectors, this makes switch even more useful for pattern matching. This is a preview language feature .
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JEP 400: UTF-8 by Default
Specify UTF-8 as the default charset of the standard Java APIs. With this change, APIs that depend upon the default charset will behave consistently across all implementations, operating systems, locales, and configurations.
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Java JEP 461: Stream Gatherers
Enhance the Stream API to support custom intermediate operations. This will allow stream pipelines to transform data in ways that are not easily achievable with the existing built-in intermediate operations. This is a preview API .
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JEP 544: Ahead-of-Time Code Compilation
Improve startup and warmup time by making optimized native code for an application instantly available when the HotSpot Java Virtual Machine starts. Achieve this by compiling application code to native code in a training run, storing the native code in the AOT cache for use in subsequent production runs. If the…
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JEP 540: Simple JSON API (Now in Incubator)
Define a simple, standard API for parsing and generating JSON documents so that doing so does not require an external library. Enable many JSON processing tasks to be accomplished with little coding. This is an incubating API .
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JEP 457: Class-File API for Parsing, generating, transforming Java classfiles
Provide a standard API for parsing, generating, and transforming Java class files. This is a preview API .
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JEP 515: Ahead-of-Time Method Profiling
Improve warmup time by making method-execution profiles from a previous run of an application instantly available, when the HotSpot Java Virtual Machine starts. This will enable the JIT compiler to generate native code immediately upon application startup, rather than having to wait for profiles to be collected.
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JEP 454: Foreign Function and Memory API
Introduce an API by which Java programs can interoperate with code and data outside of the Java runtime. By efficiently invoking foreign functions (i.e., code outside the JVM), and by safely accessing foreign memory (i.e., memory not managed by the JVM), the API enables Java programs to call native libraries and…