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Java

Jigsaw encapsulation: Running NetLogo 6.0 with Java 9

NetLogo is a multi-agent programmable modeling environment that runs on Java. Recently NetLogo 6.0 has been released. I wanted to try NetLogo 6.0 with a recent...

NetLogo is a multi-agent programmable modeling environment that runs on Java. Recently NetLogo 6.0 has been released. I wanted to try NetLogo 6.0 with a recent Java 9 (local) build. Running NetLogo 6.0 with Java 9I installed NetLogo 6.0 and ran it with the following Java command line:$ ~/src/jdk9-dev/build/macosx-x86_64-normal-server-release/images/jdk/bin/java -jar Java/netlogo-6.0.0.jar Exception - stack traceJust after showing NetLogo splash screen, the above Java command...

Java

Exploring Layers and Modules in #java9 using #nashorn

Java

Accessing Python objects from Nashorn JavaScript

Dynamic linker API for the Java platform (JEP 276) in JDK 9 Early Access defines dynamic linker API for the Java platform. Using this API, different language...

Dynamic linker API for the Java platform (JEP 276) in JDK 9 Early Access defines dynamic linker API for the Java platform. Using this API, different language runtimes implemented for the Java platform can interoperate with each other. Nashorn JavaScript engine has been a part of JDK platform since JDK 8. Jython is an implementation of the Python programming language designed to run on the Java platform. In this blog entry, I'll demonstrate seamless access of Python objects...

Java

Writing a pluggable dynalink linker and using it with Nashorn

JEP-276 (JEP 276: Dynamic Linking of Language-Defined Object Models) adds a facility for linking high-level operations on objects such as "read a property",...

JEP-276 (JEP 276: Dynamic Linking of Language-Defined Object Models) adds a facility for linking high-level operations on objects such as "read a property", "write a property", "invoke a callable object", etc., expressed as names in INVOKEDYNAMIC call sites. Nashorn JavaScript engine in OpenJDK uses dynalink for linking script and other objects. JEP 276 allows user written ("pluggable") linkers to be loaded via service loader mechanism. Because of Dynalink, Nashorn also...

Java

Using Dynalink API with invokedynamic - a Java assembler example

Dynalink API JEP-276Dynalink API (http://openjdk.java.net/jeps/276) provides a facility for linking high-level operations on objects such as "read a property",...

Dynalink API JEP-276Dynalink API (http://openjdk.java.net/jeps/276) provides a facility for linking high-level operations on objects such as "read a property", "write a property", "invoke a callable object", etc., expressed as names in INVOKEDYNAMIC call sites. Dynalink also provides a default linker for the usual semantics of these operations on plain Java objects (Java POJO "beans" linker), as well as a facility for installing your own language-specific linkers.Dynalink has...

Java

Dynamic linker API for the Java platform (JEP 276)

JEP 276 defines dynamic linker API for Java. This JEP provides "facility for linking high-level operations on objects such as "read a property", "write a...

JEP 276 defines dynamic linker API for Java. This JEP provides "facility for linking high-level operations on objects such as "read a property", "write a property", "invoke a callable object", etc., expressed as names in INVOKEDYNAMIC call sites. Provide a default linker for the usual semantics of these operations on plain Java objects, as well as a facility for installing language-specific linkers.Nashorn JavaScript engine already uses "dynalink" library for linking...

Java

Underscore is a keyword in Java 9, use this script to check your code!

Underscore ("_") is a keyword in Java 9. If you use "_" as an identifier, javac of JDK 8+ issues a warning. javac of JDK 9, issues an error! To check and...

Underscore ("_") is a keyword in Java 9. If you use "_" as an identifier, javac of JDK 8+ issues a warning. javac of JDK 9, issues an error! To check and migrate your Java code to avoid using "_" as an identifier, you can use the following Nashorn script with jjs tool. This script just parses each .java file and reports "_" variables with filename, line and column numbers. This script uses Javac Tool API and Compiler Tree API.File: find_underscore.js// Usage: jjs...

Java

Playing with Java (java9) REPL - an example that uses nashorn engine in REPL

I love "Exploratory Programming" (https://en.wikipedia.org/wiki/Exploratory_programming) tools. If you've not already played with "Java REPL" project, you may...

I love "Exploratory Programming" (https://en.wikipedia.org/wiki/Exploratory_programming) tools. If you've not already played with "Java REPL" project, you may want to do so! Check out Kulla project.Clone kulla forest @ http://hg.openjdk.java.net/kulla and build using these commands:hg clone http://hg.openjdk.java.net/kulla/dev kulla-devcd kulla-devsh get_sources.shsh configure --with-boot-jdk=/path/to/jdk1.8.0make clean imagesmake install Once build finishes, you can use the...

Java

Look Ma, javac tells me I am overriding static method wrongly!!

// File: SuperClass.javapublic class SuperClass { public static int func() { return 0; }}// File: SubClass.javapublic class SubClass extends SuperClass { public...

// File: SuperClass.javapublic class SuperClass { public static int func() { return 0; }}// File: SubClass.javapublic class SubClass extends SuperClass { public static boolean func() { return false; }}$ javac -fullversionjavac full version "1.6.0_15-b03-226"javac SuperClass.java SubClass.java SubClass.java:2: func() in SubClass cannot override func() in SuperClass; attempting to use incompatible return typefound : booleanrequired: int public static boolean func() { \^1...