Groovy example source code file (SpreadDotTest.groovy)

This example Groovy source code file (SpreadDotTest.groovy) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Groovy tags/keywords

a, book1, book2, book3, hello, large, object, object, spreaddotdemo, spreaddotdemo, spreaddotdemo2, spreaddotdemo2, string, string

The Groovy SpreadDotTest.groovy source code

/*
 * Copyright 2003-2008 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
 package groovy

/**
 * Test for the spread dot operator "*.".
 *
 * For an example,
 *          list*.property
 * means
 *          list.collect { it?.property }
 *
 * @author  Pilho Kim
 * @author  Paul King
 */
public class SpreadDotTest extends GroovyTestCase {
    void testSpreadDot() {
        def m1 = ["a":1, "b":2]
        def m2 = ["a":11, "b":22]
        def m3 = ["a":111, "b":222]
        def x = [m1,m2,m3]
        println x*.a
        println x*."a"
        assert x == [m1, m2, m3]

        def m4 = null
        x << m4
        println x*.a
        println x*."a"
        assert x == [m1, m2, m3, null]

        def d = new SpreadDotDemo()
        x << d
        println x*."a"
        assert x == [m1, m2, m3, null, d]

        def y = new SpreadDotDemo2()
        println y."a"
        println y.a

        x << y
        println x*."a"
        assert x == [m1, m2, m3, null, d, y]
    }

    void testSpreadDot2() {
        def a = new SpreadDotDemo()
        def b = new SpreadDotDemo2()
        def x = [a, b]

        assert x*.fnB("1") == [a.fnB("1"), b.fnB("1")]
        assert [a,b]*.fnB() == [a.fnB(), b.fnB()]
    }

    void testSpreadDotArrays() {
        def a = new SpreadDotDemo()
        def b = new SpreadDotDemo2()
        Object[] x = [a, b]

        assert x*.fnB("1") == [a.fnB("1"), b.fnB("1")]
        assert [a,b]*.fnB() == [a.fnB(), b.fnB()]

        int[] nums = [3, 4, 5]
        assert nums*.toString() == ['3', '4', '5']

        boolean[] answers = [true, false, true]
        assert answers*.toString() == ['true', 'false', 'true']

        String[] pets = ['ant', 'bear', 'camel']
        assert pets*.length() == nums
    }

    void testSpreadDotOnArrays2 () {
        def books = [Book1, Book2, Book3] as Object[]

        books*.metaClass*.foo = { "Hello, ${delegate.class.name}" }

        assertEquals "Hello, groovy.Book1", new Book1 ().foo ()
        assertEquals "Hello, groovy.Book2", new Book2 ().foo ()
        assertEquals "Hello, groovy.Book3", new Book3 ().foo ()
    }
    
    void testSpreadDotAdvanced() {
        assertEquals ([3, 3], ['cat', 'dog']*.size())
        assertEquals ([3, 3], (['cat', 'dog'] as Vector)*.size())
        assertEquals ([3, 3], (['cat', 'dog'] as String[])*.size())
        assertEquals ([3, 3], (['cat', 'dog'] as Vector).elements()*.size())
        assertEquals ([1, 1, 1], 'zoo'*.size())
        assertEquals (Object, new Object().getClass())
        assertEquals ([Object], new Object()*.getClass())
        assertEquals ('Large', new Shirt().size())
        assertEquals (['Large'], new Shirt()*.size())
    }

    void testSpreadDotMap () {
        def map = [A:"one", B:"two", C:"three"]
        assert map.collect { child ->  child.value.size() } == [3, 3, 5]
        assert map*.value*.size() == [3, 3, 5]
        assert map*.getKey() == ['A', 'B', 'C']
    }

    public void testSpreadDotAttribute() {
        def s = new Singlet()
        assert s.size == 1
        assert s.@size == 12
        def wardrobe = [s, s]
        assert wardrobe*.size == [1, 1]
        assert wardrobe*.@size == [12, 12]
    }
}

class SpreadDotDemo {
    public java.util.Date getA() {
        return new Date()
    }
    public String fnB() {
        return "bb"
    }
    public String fnB(String m) {
        return "BB$m"
    }
}

class SpreadDotDemo2 {
    public String getAttribute(String key) {
        return "Attribute $key"
    }
    public String get(String key) {
        return getAttribute("Get $key")
    }
    public String fnB() {
        return "cc"
    }
    public String fnB(String m) {
        return "CC$m"
    }
}


class Book1 {}
class Book2 {}
class Book3 {}

class Shirt {
    def size() { 'Large' } 
}

class Singlet {
    private size = 12
    def getSize() {1}
}