Groovy example source code file (ForLoopTest.groovy)

This example Groovy source code file (ForLoopTest.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

class, class, forlooptest, integer, integer, iterator, string, string, the, the, vector

The Groovy ForLoopTest.groovy source code

/*
 * Copyright 2003-2010 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

import groovy.bugs.TestSupport

class ForLoopTest extends gls.CompilableTestSupport {

    def x

    void testFinalParameterInForLoopIsAllowed() {
        // only 'final' should be allowed: other modifiers like 'synchronized' should be forbidden
        shouldNotCompile """
            def collection = ["a", "b", "c", "d", "e"]
            for (synchronized String letter in collection) { }            
        """

        // only 'final' allowed, and no additional modifier
        shouldNotCompile """
            def collection = ["a", "b", "c", "d", "e"]
            for (final synchronized String letter in collection) { }
        """

        shouldCompile """
            def collection = ["a", "b", "c", "d", "e"]
            for (final String letter in collection) { }
            for (final String letter : collection) { }
            for (final letter in collection) { }
            for (final letter : collection) { }
        """
    }

    void testRange() {
        x = 0

        for (i in 0..9) {
            x = x + i
        }

        assert x == 45
    }

    void testRangeWithType() {
        x = 0

        for (Integer i in 0..9) {
            assert i.getClass() == Integer
            x = x + i
        }

        assert x == 45
    }

    void testRangeWithJdk15StyleAndType() {
        x = 0

        for (Integer i: 0..9) {
            assert i.getClass() == Integer
            x = x + i
        }

        assert x == 45
    }

    void testList() {
        x = 0

        for (i in [0, 1, 2, 3, 4]) {
            x = x + i
        }

        assert x == 10
    }

    void testArray() {
        def array = (0..4).toArray()

        println "Class: ${array.getClass()} for array ${array}"

        x = 0

        for (i in array) {
            x = x + i
        }

        assert x == 10
    }

    void testIntArray() {
        def array = TestSupport.getIntArray()

        println "Class: ${array.getClass()} for array ${array}"

        x = 0

        for (i in array) {
            x = x + i
        }

        assert x == 15
    }

    void testString() {
        def text = "abc"

        def list = []
        for (c in text) {
            list.add(c)
        }

        assert list == ["a", "b", "c"]
    }

    void testVector() {
        def vector = new Vector()
        vector.addAll([1, 2, 3])

        def answer = []
        for (i in vector.elements()) {
            answer << i
        }
        assert answer == [1, 2, 3]
    }

    void testClassicFor() {
        def sum = 0
        for (int i = 0; i < 10; i++) {
            sum++
        }
        assert sum == 10

        def list = [1, 2]
        sum = 0
        for (Iterator i = list.iterator(); i.hasNext();) {
            sum += i.next()
        }
        assert sum == 3
    }

    void testClassicForNested() {
        def sum = 0
        for (int i = 0; i < 10; i++) {
            for (int j = 0; j < 10; j++) {
                sum++
            }
        }
        assert sum == 100
    }

    void testClassicForWithContinue() {
        def sum1 = 0
        for (int i = 0; i < 10; i++) {
            if (i % 2 == 0) continue
            sum1 += i
        }
        assert sum1 == 25

        // same as before, but with label
        def sum2 = 0
        test:
        for (int i = 0; i < 10; i++) {
            if (i % 2 == 0) continue test
            sum2 += i
        }
        assert sum2 == 25

    }

    void testClassicForWithEmptyInitializer() {
        def i = 0
        def sum1 = 0
        for (; i < 10; i++) {
            if (i % 2 == 0) continue
            sum1 += i
        }
        assert sum1 == 25
    }

    void testClassicForWithEmptyBody() {
        int i
        for (i = 0; i < 5; i++);
        assert i == 5
    }

    void testClassicForWithEverythingInitCondNextExpressionsEmpty() {
        int counter = 0
        for (;;) {
            counter++
            if (counter == 10) break
        }

        assert counter == 10, "The body of the for loop wasn't executed, it should have looped 10 times."
    }

}