Ateji PX is an extension of Java for parallel programs. It adds a || operator for statement and data parallelism and ! and ? operators for message passing. It is implemented as an Eclipse plugin that precompiles the code.
Kotlin is a statically-typed JVM-targeted programming language intended for industrial use.
Gosu is an is object oriented, statically typed language which claims to be 100% compatible with Java. It features type inference, supports closures and aims to provide simplified generics.
jContractor is a 100% pure Java implementation of Design By Contract for the Java language. Contracts are written as methods that follow a simple naming convention. jContractor provides runtime contract checking by instrumenting the bytecode of classes that define contracts. jContractor can either add contract checking code to class files to be executed later, or it can instrument classes at runtime as they are loaded. All contracts are written in standard Java.
Stab is a multi-paradigm programming language designed for the Java Virtual Machine. It features JVM compatibility, implicitly typed variables, delegates, Lambda expressions, iterator blocks, Extension methods, properties and indexers, anonymous objects, language integrated queries and automatic resources management.
A compiler for the Micro Java language. French documentation only.
Guarana is a reflective architecture that aims at simplicity, flexibility, security and reuse of meta-level code. It features a run-time meta-object protocol that provides for easy composition of meta-objects and allows for dynamic reconfiguration. Meta-objects can be combined through composers, that provide the glue code for them to work together, delegating control to them and resolving conflicts when they arise. Since composers are meta-objects, they can be further composed.