Groovy MOP

RowSet.groovy

package mop

class RowSet {
    Map map = [:]
    void update(key,value){
        map.put(key,value)
    }
    def get(key){
        map.get(key)
    }
}

// Using methodMissing with dynamic method registration
class GORM {
    def dynamicMethods = [] // an array of dynamic methods that use regex
    def methodMissing(String name, args) {
        def method = dynamicMethods.find { it.match(name) }
        if(method) {
            GORM.metaClass."$name" = { Object[] varArgs ->
                method.invoke(delegate, name, varArgs)
            }
            return method.invoke(delegate,name, args)
        }
        else throw new MissingMethodException(name, delegate, args)
    }
}

// property getter
class Foo2 {
    def propertyMissing(String name) { name }
}

// property getter and setter
class Foo1 {
    def storage = [:]
    def propertyMissing(String name, value) { storage[name] = value }
    def propertyMissing(String name) { storage[name] }
}

TestMop.groovy

package mop

//http://groovy.codehaus.org/Using+methodMissing+and+propertyMissing
//http://stackoverflow.com/questions/7078855/groovy-dynamically-add-properties-to-groovy-classes-from-inside-class-methods
class Run extends GroovyTestCase {
    void test1() {
        RowSet.metaClass.each = { Closure closure ->

            Map map = delegate.map
            if (map != null && map.size() > 0) {
                map.each { k, v ->
                    closure.call(k, v)
                }
            }
//            closure.call(delegate)
        }
        def rst = new RowSet(map: ['a': 1, 'b': 2, 'c': 'ccc'])

        rst.each { k, v ->
            println "$k,$v"
        }
    }

    void test2() {
        RowSet.metaClass.invokeMethod = { String name, args ->
            def m = RowSet.metaClass.getMetaMethod(name, args)
            if (m!=null)
                return m.invoke(delegate, args)
            return delegate.get(name)
        }
        RowSet.metaClass.propertyMissing={String name->
            return Math.random()
        }
        def rst = new RowSet(map: ['-1':'abc','a': 1, 'b': 2, 'c': 'ccc'])
        // method
        println rst.'-1'()
        println rst.'a'()
        println rst.a()
        // property
        println rst.a
        println(rst.bcde)
        println rst.a
    }
}