jscl-meditor is a Java symbolic computing library and math editor. It includes polynomial system solving, vectors and matrices, factorization, derivatives, integrals (rational functions), boolean algebra, simplification, MathML output, Java code generation, and geometric algebra.
In this release, the integer fractions appear at the head of expressions. Some work was done on the Groebner Basis code.
URL: jscl-meditor - java symbolic computing library and mathematical editor