Skip to content

Latest commit

 

History

History

java-11

README.md

Java 11

To run each example use:

sh build.sh
java -cp bin <ClassName>

JEPs

  • 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

Features

  • Removal of Modules and Deprecated API
    • removal of Java EE Modules:
      • JAF
      • CORBA
      • JTA
      • JAXB
      • JAX-WS
      • Commons Annotation
    • JavaFX
  • Scripting
  • Shebang
    • #!/opt/jdk-11/bin/java --source 11
  • var in Lambda Expressions
    • allowing to use annotation without specifying the type
    • .filter((@Nonnull var item) -> isAllowed(item))

API

  • String
    • lines(): to streaming the lines from a string
    • strip(), stripLeading() and stripTrailing()
    • repeat(int)
    • isBlank()
  • Path
    • of(String, String...) and of(URI)
  • Files
    • readString(Path): read the entire content from a file as a String - Files.readString(Path.of("message.txt"))
    • writeString(Path, CharSequence, OpenOption...) write a String to a file - Files.writeString(Path.of("message.txt"), updatedMessage)
  • Null I/O
    • InputStream.nullInputStream(): empty input stream
    • OutputStream.nullOutputStream(): output stream that discards input bytes
    • Reader.nullReader(): empty reader
    • Writer.nullWriter(): writer that discards input content
  • New better way to turn a collection into an array
    • String[] array = list.toArray(String[]::new)
  • Optional::isEmpty
  • Predicate::not
  • Pattern::asMatchPredicate

JVM

  • CDS
    • The Class data sharing (CDS) feature helps reduce the startup time and memory footprint between multiple Java Virtual Machines (JVM).
    • To use CDS we need permition to write to lib dir: $JAVA_HOME/lib/server/classes.jsa
    • Steps:
      • First we need to generate the class list with the loaded classes: java -XX:DumpLoadedClassList=<my-classes-list-file.lst>
      • Then generate the dump using the class list: java -XX:SharedClassListFile=<my-classes-list-file.jsa> -Xshare:dump
      • To use: java -XX:SharedArchiveFile=<my-classes-list-file.jsa>

Links