Here is an example using the standard (Java 1.6+) scripting library:
import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;
public class Test {
public static void main(String[] args) throws Exception {
ScriptEngineManager factory = new ScriptEngineManager();
ScriptEngine engine = factory.getEngineByName("JavaScript");
engine.eval("value = 10");
Boolean greaterThan5 = (Boolean) engine.eval("value > 5");
Boolean lessThan5 = (Boolean) engine.eval("value < 5");
System.out.println("10 > 5? " + greaterThan5); // true
System.out.println("10 < 5? " + lessThan5); // false
}
}