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 package org.openide.util;

 import java.util.ArrayList;

 import java.util.Arrays;

 import java.util.Collection;

 import java.util.Collections;

 import java.util.Enumeration;

 import java.util.Iterator;

 import java.util.List;

 import java.util.Map;

 import java.util.NoSuchElementException;

 import java.util.Set;

 import org.netbeans.junit.NbTestCase;

 /** This is the base test for new and old enumerations. It contains

  * factory methods for various kinds of enumerations and set of tests

  * that use them. Factory methods are overriden in OldEnumerationsTest

  *

  * @author Jaroslav Tulach

  */

 public class EnumerationsTest extends NbTestCase {

     /** Creates a new instance of EnumerationsTest */

     public EnumerationsTest(String testName) {

         super(testName);

     }

     //

     // Factory methods

     //

     protected <T> Enumeration<T> singleton(T obj) {

         return Enumerations.singleton(obj);

     }

     protected <T> Enumeration<T> concat(Enumeration<T> en1, Enumeration<T> en2) {

         return Enumerations.concat(en1, en2);

     }

     protected <T> Enumeration<T> concat(Enumeration<Enumeration<T>> enumOfEnums) {

         return Enumerations.concat(enumOfEnums);

     }

     protected <T> Enumeration<T> removeDuplicates(Enumeration<T> en) {

         return Enumerations.removeDuplicates(en);

     }

     protected <T> Enumeration<T> empty() {

         return Enumerations.empty();

     }

     protected <T> Enumeration<T> array(T[] arr) {

         return Enumerations.array(arr);

     }

     protected <T,R> Enumeration<R> convert(Enumeration<T> en, final Map<T,R> map) {

         class P implements Enumerations.Processor<T,R> {

             public R process(T obj, Collection<T> nothing) {

                 return map.get(obj);

             }

         }

         return Enumerations.convert(en, new P());

     }

     protected <T> Enumeration<T> removeNulls(Enumeration<T> en) {

         return Enumerations.removeNulls(en);

     }

     protected <T> Enumeration<T> filter(Enumeration<T> en, final Set<T> filter) {

         class P implements Enumerations.Processor<T,T> {

             public T process(T obj, Collection<T> nothing) {

                 return filter.contains(obj) ? obj : null;

             }

         }

         return Enumerations.filter(en, new P());

     }

     protected <T,R> Enumeration<R> filter(Enumeration<T> en, final QueueProcess<T,R> filter) {

         class P implements Enumerations.Processor<T,R> {

             public R process(T obj, Collection<T> nothing) {

                 return filter.process(obj, nothing);

             }

         }

         return Enumerations.filter(en, new P());

     }

     /**

      * @param filter the set.contains (...) is called before each object is produced

      * @return Enumeration

      */

     protected <T,R> Enumeration<R> queue(Collection<T> initContent, final QueueProcess<T,R> process) {

         class C implements Enumerations.Processor<T,R> {

             public R process(T object, Collection<T> toAdd) {

                 return process.process(object, toAdd);

             }

         }

         return Enumerations.queue(

                 Collections.enumeration(initContent),

                 new C()

                 );

     }

     /** Processor interface.

      */

     public static interface QueueProcess<T,R> {

         public R process(T object, Collection<T> toAdd);

     }

     //

     // The tests

     //

     public void testEmptyIsEmpty() {

         Enumeration e = empty();

         assertFalse(e.hasMoreElements());

         try {

             e.nextElement();

             fail("No elements");

         } catch (NoSuchElementException ex) {

             // ok

         }

     }

     public void testSingleIsSingle() {

         Enumeration e = singleton(this);

         assertTrue(e.hasMoreElements());

         assertEquals("Returns me", this, e.nextElement());

         assertFalse("Now it is empty", e.hasMoreElements());

         try {

             e.nextElement();

             fail("No elements");

         } catch (NoSuchElementException ex) {

             // ok

         }

     }

     public void testConcatTwoAndArray() {

         Object[] one = { 1, 2, 3 };

         Object[] two = { "1", "2", "3" };

         List<Object> list = new ArrayList<Object>(Arrays.asList(one));

         list.addAll(Arrays.asList(two));

         assertEnums(

                 concat(array(one), array(two)),

                 Collections.enumeration(list)

                 );

     }

     public void testConcatTwoAndArrayAndTakeOnlyStrings() {

         Object[] one = { 1, 2, 3 };

         Object[] two = { "1", "2", "3" };

         Object[] three = { 1L };

         Object[] four = { "Kuk" };

         List<Object> list = new ArrayList<Object>(Arrays.asList(two));

         list.addAll(Arrays.asList(four));

         @SuppressWarnings("unchecked")

         Enumeration<Object>[] alls = (Enumeration<Object>[]) new Enumeration<?>[] {

             array(one), array(two), array(three), array(four)

         };

         assertEnums(

                 filter(concat(array(alls)), new OnlyStrings()),

                 Collections.enumeration(list)

                 );

     }

     public void testRemoveDuplicates() {

         Object[] one = { 1, 2, 3 };

         Object[] two = { "1", "2", "3" };

         Object[] three = { 1 };

         Object[] four = { "2", "3", "4" };

         @SuppressWarnings("unchecked")

         Enumeration<Object>[] alls = (Enumeration<Object>[]) new Enumeration<?>[] {

             array(one), array(two), array(three), array(four)

         };

         assertEnums(

                 removeDuplicates(concat(array(alls))),

                 array(new Object[] { 1, 2, 3, "1", "2", "3", "4" })

                 );

     }

     public void testRemoveDuplicatesAndGCWorks() {

         /*** Return { i1, "", "", "", i2 } */

         class WeakEnum implements Enumeration<Object> {

             public Object i1 = new Integer(1);

             public Object i2 = new Integer(1);

             private int state;

             public boolean hasMoreElements() {

                 return state < 5;

             }

             public Object nextElement() {

                 switch (state++) {

                     case 0: return i1;

                     case 1: case 2: case 3: return "";

                     default: return i2;

                 }

             }

         }

         WeakEnum weak = new WeakEnum();

         Enumeration en = removeDuplicates(weak);

         assertTrue("Has some elements", en.hasMoreElements());

         assertEquals("And the first one is get", weak.i1, en.nextElement());

         /*

         try {

             Reference<?> ref = new WeakReference<Object>(weak.i1);

          */

             weak.i1 = null;

         /*

             assertGC("Try hard to GC the first integer", ref);

             // does not matter whether it GCs or not

         } catch (Throwable tw) {

             // not GCed, but does not matter

         }

          */

         assertTrue("Next object will be string", en.hasMoreElements());

         assertEquals("is empty string", "", en.nextElement());

         assertFalse("The second integer is however equal to the original i1 and thus" +

                 " the enum should not be there", en.hasMoreElements());

     }

     public void testQueueEnum() {

         class Pr implements QueueProcess<Integer,Integer> {

             public Integer process(Integer i, Collection<Integer> c) {

                 int plus = i + 1;

                 if (plus < 10) {

                     c.add(plus);

                 }

                 return i;

             }

         }

         Pr p = new Pr();

         Enumeration en = queue(

                 Collections.nCopies(1, 0), p

                 );

         for (int i = 0; i < 10; i++) {

             assertTrue("has next", en.hasMoreElements());

             en.nextElement();

         }

         assertFalse("No next element", en.hasMoreElements());

     }

     public void testFilteringAlsoDoesConvertions() throws Exception {

         class Pr implements QueueProcess<Integer,Integer> {

             public Integer process(Integer i, Collection<Integer> ignore) {

                 return i + 1;

             }

         }

         Pr p = new Pr();

         Enumeration<Integer> onetwo = array(new Integer[] { 1, 2 });

         Enumeration<Integer> twothree = array(new Integer[] { 2, 3 });

         assertEnums(

                 filter(onetwo, p), twothree

                 );

     }

     private static <T> void assertEnums(Enumeration<T> e1, Enumeration<T> e2) {

         int indx = 0;

         while (e1.hasMoreElements() && e2.hasMoreElements()) {

             T i1 = e1.nextElement();

             T i2 = e2.nextElement();

             assertEquals(indx++ + "th: ", i1, i2);

         }

         if (e1.hasMoreElements()) {

             fail("first one contains another element: " + e1.nextElement());

         }

         if (e2.hasMoreElements()) {

             fail("second one contains another element: " + e2.nextElement());

         }

         try {

             e1.nextElement();

             fail("First one should throw exception, but nothing happend");

         } catch (NoSuchElementException ex) {

             // ok

         }

         try {

             e2.nextElement();

             fail("Second one should throw exception, but nothing happend");

         } catch (NoSuchElementException ex) {

             // ok

         }

     }

     public void testConvertIntegersToStringRemoveNulls() {

         Object[] garbage = { 1, "kuk", "hle", 5 };

         assertEnums(

                 removeNulls(convert(array(garbage), new MapIntegers())),

                 array(new Object[] { "1", "5" })

                 );

     }

     public void testQueueEnumerationCanReturnNulls() {

         Object[] nuls = { null, "NULL" };

         class P implements QueueProcess<Object,Object> {

             public Object process(Object toRet, Collection<Object> toAdd) {

                 if (toRet == null) return null;

                 if ("NULL".equals(toRet)) {

                     toAdd.add(null);

                     return null;

                 }

                 return null;

             }

         }

         assertEnums(

                 array(new Object[] { null, null, null }),

                 queue(Arrays.asList(nuls), new P())

                 );

     }

     /** Filters only strings.

      */

     private static final class OnlyStrings implements Set<Object> {

         public boolean add(Object o) {

             fail("Should not be every called");

             return false;

         }

         public boolean addAll(Collection c) {

             fail("Should not be every called");

             return false;

         }

         public void clear() {

             fail("Should not be every called");

         }

         public boolean contains(Object o) {

             return o instanceof String;

         }

         public boolean containsAll(Collection c) {

             fail("Should not be every called");

             return false;

         }

         public boolean isEmpty() {

             fail("Should not be every called");

             return false;

         }

         public Iterator<Object> iterator() {

             fail("Should not be every called");

             return null;

         }

         public boolean remove(Object o) {

             fail("Should not be every called");

             return false;

         }

         public boolean removeAll(Collection c) {

             fail("Should not be every called");

             return false;

         }

         public boolean retainAll(Collection c) {

             fail("Should not be every called");

             return false;

         }

         public int size() {

             fail("Should not be every called");

             return 1;

         }

         public Object[] toArray() {

             fail("Should not be every called");

             return null;

         }

         public <T> T[] toArray(T[] a) {

             fail("Should not be every called");

             return null;

         }

     }

     /** Filters only strings.

      */

     private static final class MapIntegers implements Map<Object,Object> {

         public boolean containsKey(Object key) {

             fail("Should not be every called");

             return false;

         }

         public boolean containsValue(Object value) {

             fail("Should not be every called");

             return false;

         }

         public Set<Map.Entry<Object,Object>> entrySet() {

             fail("Should not be every called");

             return null;

         }

         public Object get(Object key) {

             if (key instanceof Integer) {

                 return key.toString();

             }

             return null;

         }

         public Set<Object> keySet() {

             fail("Should not be every called");

             return null;

         }

         public Object put(Object key, Object value) {

             fail("Should not be every called");

             return null;

         }

         public void putAll(Map t) {

             fail("Should not be every called");

         }

         public Collection<Object> values() {

             fail("Should not be every called");

             return null;

         }

         public void clear() {

             fail("Should not be every called");

         }

         public boolean isEmpty() {

             fail("Should not be every called");

             return false;

         }

         public Object remove(Object key) {

             fail("Should not be every called");

             return null;

         }

         public int size() {

             fail("Should not be every called");

             return 1;

         }

     }

 }