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Java example source code file (ListsTest.java)

This example Java source code file (ListsTest.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

arraylist, copyonwritearraylist, gwtincompatible, iterator, iteratortester, list, override, randomaccess, some_function, string, suppresswarnings, teststringlistgenerator, threading, threads, unmodifiable, unsupportedoperationexception, util

The ListsTest.java Java example source code

/*
 * Copyright (C) 2007 The Guava 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 com.google.common.collect;

import static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.collect.testing.IteratorFeature.UNMODIFIABLE;
import static com.google.common.truth.Truth.assertThat;
import static java.util.Arrays.asList;
import static java.util.Collections.singletonList;

import com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.GwtIncompatible;
import com.google.common.base.Function;
import com.google.common.base.Functions;
import com.google.common.collect.testing.IteratorTester;
import com.google.common.collect.testing.ListTestSuiteBuilder;
import com.google.common.collect.testing.TestStringListGenerator;
import com.google.common.collect.testing.features.CollectionFeature;
import com.google.common.collect.testing.features.CollectionSize;
import com.google.common.collect.testing.features.ListFeature;
import com.google.common.collect.testing.google.ListGenerators.CharactersOfCharSequenceGenerator;
import com.google.common.collect.testing.google.ListGenerators.CharactersOfStringGenerator;
import com.google.common.testing.NullPointerTester;
import com.google.common.testing.SerializableTester;

import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;

import org.easymock.EasyMock;

import java.io.Serializable;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.ListIterator;
import java.util.NoSuchElementException;
import java.util.RandomAccess;
import java.util.concurrent.CopyOnWriteArrayList;

/**
 * Unit test for {@code Lists}.
 *
 * @author Kevin Bourrillion
 * @author Mike Bostock
 * @author Jared Levy
 */
@GwtCompatible(emulated = true)
public class ListsTest extends TestCase {

  private static final Collection<Integer> SOME_COLLECTION
      = asList(0, 1, 1);

  private static final Iterable<Integer> SOME_ITERABLE = new SomeIterable();

  private static final class RemoveFirstFunction
      implements Function<String, String>, Serializable {
    @Override
    public String apply(String from) {
      return (from.length() == 0) ? from : from.substring(1);
    }
  }

  private static class SomeIterable implements Iterable<Integer>, Serializable {
    @Override
    public Iterator<Integer> iterator() {
      return SOME_COLLECTION.iterator();
    }
    private static final long serialVersionUID = 0;
  }

  private static final List<Integer> SOME_LIST
      = Lists.newArrayList(1, 2, 3, 4);

  private static final List<Integer> SOME_SEQUENTIAL_LIST
      = Lists.newLinkedList(asList(1, 2, 3, 4));

  private static final List<String> SOME_STRING_LIST
      = asList("1", "2", "3", "4");

  private static final Function<Number, String> SOME_FUNCTION
      = new SomeFunction();

  private static class SomeFunction
      implements Function<Number, String>, Serializable {
    @Override
    public String apply(Number n) {
      return String.valueOf(n);
    }
    private static final long serialVersionUID = 0;
  }

  @GwtIncompatible // suite
  public static Test suite() {
    TestSuite suite = new TestSuite();
    suite.addTestSuite(ListsTest.class);

    suite.addTest(ListTestSuiteBuilder.using(new TestStringListGenerator() {
          @Override protected List<String> create(String[] elements) {
            String[] rest = new String[elements.length - 1];
            System.arraycopy(elements, 1, rest, 0, elements.length - 1);
            return Lists.asList(elements[0], rest);
          }
        })
        .named("Lists.asList, 2 parameter")
        .withFeatures(CollectionSize.SEVERAL, CollectionSize.ONE,
            CollectionFeature.SERIALIZABLE,
            CollectionFeature.ALLOWS_NULL_VALUES)
        .createTestSuite());

    suite.addTest(ListTestSuiteBuilder.using(new TestStringListGenerator() {
          @Override protected List<String> create(String[] elements) {
            String[] rest = new String[elements.length - 2];
            System.arraycopy(elements, 2, rest, 0, elements.length - 2);
            return Lists.asList(elements[0], elements[1], rest);
          }
        })
        .named("Lists.asList, 3 parameter")
        .withFeatures(CollectionSize.SEVERAL,
            CollectionFeature.SERIALIZABLE,
            CollectionFeature.ALLOWS_NULL_VALUES)
        .createTestSuite());

    final Function<String, String> removeFirst
        = new RemoveFirstFunction();

    suite.addTest(ListTestSuiteBuilder.using(new TestStringListGenerator() {
          @Override protected List<String> create(String[] elements) {
            List<String> fromList = Lists.newArrayList();
            for (String element : elements) {
              fromList.add("q" + checkNotNull(element));
            }
            return Lists.transform(fromList, removeFirst);
          }
        })
        .named("Lists.transform, random access, no nulls")
        .withFeatures(CollectionSize.ANY,
            ListFeature.REMOVE_OPERATIONS,
            CollectionFeature.SERIALIZABLE,
            CollectionFeature.ALLOWS_NULL_QUERIES)
        .createTestSuite());

    suite.addTest(ListTestSuiteBuilder.using(new TestStringListGenerator() {
          @Override protected List<String> create(String[] elements) {
            List<String> fromList = Lists.newLinkedList();
            for (String element : elements) {
              fromList.add("q" + checkNotNull(element));
            }
            return Lists.transform(fromList, removeFirst);
          }
        })
        .named("Lists.transform, sequential access, no nulls")
        .withFeatures(CollectionSize.ANY,
            ListFeature.REMOVE_OPERATIONS,
            CollectionFeature.SERIALIZABLE,
            CollectionFeature.ALLOWS_NULL_QUERIES)
        .createTestSuite());

    suite.addTest(ListTestSuiteBuilder.using(new TestStringListGenerator() {
          @Override protected List<String> create(String[] elements) {
            List<String> fromList = Lists.newArrayList(elements);
            return Lists.transform(fromList, Functions.<String>identity());
          }
        })
        .named("Lists.transform, random access, nulls")
        .withFeatures(CollectionSize.ANY,
            ListFeature.REMOVE_OPERATIONS,
            CollectionFeature.SERIALIZABLE,
            CollectionFeature.ALLOWS_NULL_VALUES)
        .createTestSuite());

    suite.addTest(ListTestSuiteBuilder.using(new TestStringListGenerator() {
          @Override protected List<String> create(String[] elements) {
            List<String> fromList =
                Lists.newLinkedList(asList(elements));
            return Lists.transform(fromList, Functions.<String>identity());
          }
        })
        .named("Lists.transform, sequential access, nulls")
        .withFeatures(CollectionSize.ANY,
            ListFeature.REMOVE_OPERATIONS,
            CollectionFeature.SERIALIZABLE,
            CollectionFeature.ALLOWS_NULL_VALUES)
        .createTestSuite());

    suite.addTest(ListTestSuiteBuilder.using(new TestStringListGenerator() {
      @Override protected List<String> create(String[] elements) {
        List<String> list = Lists.newArrayList();
        for (int i = elements.length - 1; i >= 0; i--)
          list.add(elements[i]);
        return Lists.reverse(list);
      }
    }).named("Lists.reverse[ArrayList]").withFeatures(CollectionSize.ANY,
        CollectionFeature.ALLOWS_NULL_VALUES, ListFeature.GENERAL_PURPOSE)
        .createTestSuite());

    suite.addTest(ListTestSuiteBuilder.using(new TestStringListGenerator() {
      @Override protected List<String> create(String[] elements) {
        String[] reverseElements = new String[elements.length];
        for (int i = elements.length - 1, j = 0; i >= 0; i--, j++)
          reverseElements[j] = elements[i];
        return Lists.reverse(asList(reverseElements));
      }
    }).named("Lists.reverse[Arrays.asList]").withFeatures(CollectionSize.ANY,
        CollectionFeature.ALLOWS_NULL_VALUES, ListFeature.SUPPORTS_SET)
        .createTestSuite());

    suite.addTest(ListTestSuiteBuilder.using(new TestStringListGenerator() {
      @Override protected List<String> create(String[] elements) {
        List<String> list = Lists.newLinkedList();
        for (int i = elements.length - 1; i >= 0; i--)
          list.add(elements[i]);
        return Lists.reverse(list);
      }
    }).named("Lists.reverse[LinkedList]").withFeatures(CollectionSize.ANY,
        CollectionFeature.ALLOWS_NULL_VALUES, ListFeature.GENERAL_PURPOSE)
        .createTestSuite());

    suite.addTest(ListTestSuiteBuilder.using(new TestStringListGenerator() {
      @Override protected List<String> create(String[] elements) {
        ImmutableList.Builder<String> builder = ImmutableList.builder();
        for (int i = elements.length - 1; i >= 0; i--)
          builder.add(elements[i]);
        return Lists.reverse(builder.build());
      }
    }).named("Lists.reverse[ImmutableList]").withFeatures(CollectionSize.ANY,
        CollectionFeature.ALLOWS_NULL_QUERIES)
        .createTestSuite());

    suite.addTest(ListTestSuiteBuilder.using(new CharactersOfStringGenerator())
        .named("Lists.charactersOf[String]").withFeatures(
            CollectionSize.ANY,
            CollectionFeature.SERIALIZABLE,
            CollectionFeature.ALLOWS_NULL_QUERIES)
            .createTestSuite());

    suite.addTest(ListTestSuiteBuilder.using(new CharactersOfCharSequenceGenerator())
        .named("Lists.charactersOf[CharSequence]").withFeatures(
            CollectionSize.ANY, CollectionFeature.ALLOWS_NULL_QUERIES)
            .createTestSuite());

    return suite;
  }

  public void testCharactersOfIsView() {
    StringBuilder builder = new StringBuilder("abc");
    List<Character> chars = Lists.charactersOf(builder);
    assertEquals(asList('a', 'b', 'c'), chars);
    builder.append("def");
    assertEquals(
        asList('a', 'b', 'c', 'd', 'e', 'f'), chars);
    builder.deleteCharAt(5);
    assertEquals(
        asList('a', 'b', 'c', 'd', 'e'), chars);
  }

  public void testNewArrayListEmpty() {
    ArrayList<Integer> list = Lists.newArrayList();
    assertEquals(Collections.emptyList(), list);
  }

  public void testNewArrayListWithCapacity() {
    ArrayList<Integer> list = Lists.newArrayListWithCapacity(0);
    assertEquals(Collections.emptyList(), list);

    ArrayList<Integer> bigger = Lists.newArrayListWithCapacity(256);
    assertEquals(Collections.emptyList(), bigger);
  }

  public void testNewArrayListWithCapacity_negative() {
    try {
      Lists.newArrayListWithCapacity(-1);
      fail();
    } catch (IllegalArgumentException expected) {
    }
  }

  public void testNewArrayListWithExpectedSize() {
    ArrayList<Integer> list = Lists.newArrayListWithExpectedSize(0);
    assertEquals(Collections.emptyList(), list);

    ArrayList<Integer> bigger = Lists.newArrayListWithExpectedSize(256);
    assertEquals(Collections.emptyList(), bigger);
  }

  public void testNewArrayListWithExpectedSize_negative() {
    try {
      Lists.newArrayListWithExpectedSize(-1);
      fail();
    } catch (IllegalArgumentException expected) {
    }
  }

  public void testNewArrayListVarArgs() {
    ArrayList<Integer> list = Lists.newArrayList(0, 1, 1);
    assertEquals(SOME_COLLECTION, list);
  }

  public void testComputeArrayListCapacity() {
    assertEquals(5, Lists.computeArrayListCapacity(0));
    assertEquals(13, Lists.computeArrayListCapacity(8));
    assertEquals(89, Lists.computeArrayListCapacity(77));
    assertEquals(22000005, Lists.computeArrayListCapacity(20000000));
    assertEquals(Integer.MAX_VALUE,
        Lists.computeArrayListCapacity(Integer.MAX_VALUE - 1000));
  }

  public void testNewArrayListFromCollection() {
    ArrayList<Integer> list = Lists.newArrayList(SOME_COLLECTION);
    assertEquals(SOME_COLLECTION, list);
  }

  public void testNewArrayListFromIterable() {
    ArrayList<Integer> list = Lists.newArrayList(SOME_ITERABLE);
    assertEquals(SOME_COLLECTION, list);
  }

  public void testNewArrayListFromIterator() {
    ArrayList<Integer> list = Lists.newArrayList(SOME_COLLECTION.iterator());
    assertEquals(SOME_COLLECTION, list);
  }

  public void testNewLinkedListEmpty() {
    LinkedList<Integer> list = Lists.newLinkedList();
    assertEquals(Collections.emptyList(), list);
  }

  public void testNewLinkedListFromCollection() {
    LinkedList<Integer> list = Lists.newLinkedList(SOME_COLLECTION);
    assertEquals(SOME_COLLECTION, list);
  }

  public void testNewLinkedListFromIterable() {
    LinkedList<Integer> list = Lists.newLinkedList(SOME_ITERABLE);
    assertEquals(SOME_COLLECTION, list);
  }

  @GwtIncompatible // CopyOnWriteArrayList
  public void testNewCOWALEmpty() {
    CopyOnWriteArrayList<Integer> list = Lists.newCopyOnWriteArrayList();
    assertEquals(Collections.emptyList(), list);
  }

  @GwtIncompatible // CopyOnWriteArrayList
  public void testNewCOWALFromIterable() {
    CopyOnWriteArrayList<Integer> list = Lists.newCopyOnWriteArrayList(
        SOME_ITERABLE);
    assertEquals(SOME_COLLECTION, list);
  }

  @GwtIncompatible // NullPointerTester
  public void testNullPointerExceptions() {
    NullPointerTester tester = new NullPointerTester();
    tester.testAllPublicStaticMethods(Lists.class);
  }

  /**
   * This is just here to illustrate how {@code Arrays#asList} differs from
   * {@code Lists#newArrayList}.
   */
  public void testArraysAsList() {
    List<String> ourWay = Lists.newArrayList("foo", "bar", "baz");
    List<String> otherWay = asList("foo", "bar", "baz");

    // They're logically equal
    assertEquals(ourWay, otherWay);

    // The result of Arrays.asList() is mutable
    otherWay.set(0, "FOO");
    assertEquals("FOO", otherWay.get(0));

    // But it can't grow
    try {
      otherWay.add("nope");
      fail("no exception thrown");
    } catch (UnsupportedOperationException expected) {
    }

    // And it can't shrink
    try {
      otherWay.remove(2);
      fail("no exception thrown");
    } catch (UnsupportedOperationException expected) {
    }
  }

  @GwtIncompatible // SerializableTester
  public void testAsList1() {
    List<String> list = Lists.asList("foo", new String[] { "bar", "baz" });
    checkFooBarBazList(list);
    SerializableTester.reserializeAndAssert(list);
    assertTrue(list instanceof RandomAccess);

    new IteratorTester<String>(5, UNMODIFIABLE,
        asList("foo", "bar", "baz"),
        IteratorTester.KnownOrder.KNOWN_ORDER) {
      @Override protected Iterator<String> newTargetIterator() {
        return Lists.asList("foo", new String[] {"bar", "baz"}).iterator();
      }
    }.test();
  }

  private void checkFooBarBazList(List<String> list) {
    assertThat(list).containsExactly("foo", "bar", "baz").inOrder();
    assertEquals(3, list.size());
    assertIndexIsOutOfBounds(list, -1);
    assertEquals("foo", list.get(0));
    assertEquals("bar", list.get(1));
    assertEquals("baz", list.get(2));
    assertIndexIsOutOfBounds(list, 3);
  }

  public void testAsList1Small() {
    List<String> list = Lists.asList("foo", new String[0]);
    assertThat(list).contains("foo");
    assertEquals(1, list.size());
    assertIndexIsOutOfBounds(list, -1);
    assertEquals("foo", list.get(0));
    assertIndexIsOutOfBounds(list, 1);
    assertTrue(list instanceof RandomAccess);

    new IteratorTester<String>(3, UNMODIFIABLE, singletonList("foo"),
        IteratorTester.KnownOrder.KNOWN_ORDER) {
      @Override protected Iterator<String> newTargetIterator() {
        return Lists.asList("foo", new String[0]).iterator();
      }
    }.test();
  }

  public void testAsList2() {
    List<String> list = Lists.asList("foo", "bar", new String[] { "baz" });
    checkFooBarBazList(list);
    assertTrue(list instanceof RandomAccess);

    new IteratorTester<String>(5, UNMODIFIABLE, asList("foo", "bar",
        "baz"), IteratorTester.KnownOrder.KNOWN_ORDER) {
      @Override protected Iterator<String> newTargetIterator() {
        return Lists.asList("foo", "bar", new String[] {"baz"}).iterator();
      }
    }.test();
  }

  @GwtIncompatible // SerializableTester
  public void testAsList2Small() {
    List<String> list = Lists.asList("foo", "bar", new String[0]);
    assertThat(list).containsExactly("foo", "bar").inOrder();
    assertEquals(2, list.size());
    assertIndexIsOutOfBounds(list, -1);
    assertEquals("foo", list.get(0));
    assertEquals("bar", list.get(1));
    assertIndexIsOutOfBounds(list, 2);
    SerializableTester.reserializeAndAssert(list);
    assertTrue(list instanceof RandomAccess);

    new IteratorTester<String>(5, UNMODIFIABLE, asList("foo", "bar"),
        IteratorTester.KnownOrder.KNOWN_ORDER) {
      @Override protected Iterator<String> newTargetIterator() {
        return Lists.asList("foo", "bar", new String[0]).iterator();
      }
    }.test();
  }

  private static void assertIndexIsOutOfBounds(List<String> list, int index) {
    try {
      list.get(index);
      fail();
    } catch (IndexOutOfBoundsException expected) {
    }
  }

  public void testReverseViewRandomAccess() {
    List<Integer> fromList = Lists.newArrayList(SOME_LIST);
    List<Integer> toList = Lists.reverse(fromList);
    assertReverseView(fromList, toList);
  }

  public void testReverseViewSequential() {
    List<Integer> fromList = Lists.newLinkedList(SOME_SEQUENTIAL_LIST);
    List<Integer> toList = Lists.reverse(fromList);
    assertReverseView(fromList, toList);
  }

  private static void assertReverseView(List<Integer> fromList,
      List<Integer> toList) {
    /* fromList modifications reflected in toList */
    fromList.set(0, 5);
    assertEquals(asList(4, 3, 2, 5), toList);
    fromList.add(6);
    assertEquals(asList(6, 4, 3, 2, 5), toList);
    fromList.add(2, 9);
    assertEquals(asList(6, 4, 3, 9, 2, 5), toList);
    fromList.remove(Integer.valueOf(2));
    assertEquals(asList(6, 4, 3, 9, 5), toList);
    fromList.remove(3);
    assertEquals(asList(6, 3, 9, 5), toList);

    /* toList modifications reflected in fromList */
    toList.remove(0);
    assertEquals(asList(5, 9, 3), fromList);
    toList.add(7);
    assertEquals(asList(7, 5, 9, 3), fromList);
    toList.add(5);
    assertEquals(asList(5, 7, 5, 9, 3), fromList);
    toList.remove(Integer.valueOf(5));
    assertEquals(asList(5, 7, 9, 3), fromList);
    toList.set(1, 8);
    assertEquals(asList(5, 7, 8, 3), fromList);
    toList.clear();
    assertEquals(Collections.emptyList(), fromList);
  }

  private static <E> List list(E... elements) {
    return ImmutableList.copyOf(elements);
  }

  @SuppressWarnings("unchecked") // varargs!
  public void testCartesianProduct_binary1x1() {
    assertThat(Lists.cartesianProduct(list(1), list(2))).contains(list(1, 2));
  }

  @SuppressWarnings("unchecked") // varargs!
  public void testCartesianProduct_binary1x2() {
    assertThat(Lists.cartesianProduct(list(1), list(2, 3)))
        .containsExactly(list(1, 2), list(1, 3)).inOrder();
  }

  @SuppressWarnings("unchecked") // varargs!
  public void testCartesianProduct_binary2x2() {
    assertThat(Lists.cartesianProduct(list(1, 2), list(3, 4)))
        .containsExactly(list(1, 3), list(1, 4), list(2, 3), list(2, 4)).inOrder();
  }

  @SuppressWarnings("unchecked") // varargs!
  public void testCartesianProduct_2x2x2() {
    assertThat(Lists.cartesianProduct(list(0, 1), list(0, 1), list(0, 1))).containsExactly(
        list(0, 0, 0), list(0, 0, 1), list(0, 1, 0), list(0, 1, 1),
        list(1, 0, 0), list(1, 0, 1), list(1, 1, 0), list(1, 1, 1)).inOrder();
  }

  @SuppressWarnings("unchecked") // varargs!
  public void testCartesianProduct_contains() {
    List<List actual = Lists.cartesianProduct(list(1, 2), list(3, 4));
    assertTrue(actual.contains(list(1, 3)));
    assertTrue(actual.contains(list(1, 4)));
    assertTrue(actual.contains(list(2, 3)));
    assertTrue(actual.contains(list(2, 4)));
    assertFalse(actual.contains(list(3, 1)));
  }

  @SuppressWarnings("unchecked") // varargs!
  public void testCartesianProduct_unrelatedTypes() {
    List<Integer> x = list(1, 2);
    List<String> y = list("3", "4");

    List<Object> exp1 = list((Object) 1, "3");
    List<Object> exp2 = list((Object) 1, "4");
    List<Object> exp3 = list((Object) 2, "3");
    List<Object> exp4 = list((Object) 2, "4");

    assertThat(Lists.<Object>cartesianProduct(x, y))
        .containsExactly(exp1, exp2, exp3, exp4).inOrder();
  }

  @SuppressWarnings("unchecked") // varargs!
  public void testCartesianProductTooBig() {
    List<String> list = Collections.nCopies(10000, "foo");
    try {
      Lists.cartesianProduct(list, list, list, list, list);
      fail("Expected IAE");
    } catch (IllegalArgumentException expected) {}
  }

  public void testTransformHashCodeRandomAccess() {
    List<String> list = Lists.transform(SOME_LIST, SOME_FUNCTION);
    assertEquals(SOME_STRING_LIST.hashCode(), list.hashCode());
  }

  public void testTransformHashCodeSequential() {
    List<String> list = Lists.transform(SOME_SEQUENTIAL_LIST, SOME_FUNCTION);
    assertEquals(SOME_STRING_LIST.hashCode(), list.hashCode());
  }

  public void testTransformModifiableRandomAccess() {
    List<Integer> fromList = Lists.newArrayList(SOME_LIST);
    List<String> list = Lists.transform(fromList, SOME_FUNCTION);
    assertTransformModifiable(list);
  }

  public void testTransformModifiableSequential() {
    List<Integer> fromList = Lists.newLinkedList(SOME_SEQUENTIAL_LIST);
    List<String> list = Lists.transform(fromList, SOME_FUNCTION);
    assertTransformModifiable(list);
  }

  private static void assertTransformModifiable(List<String> list) {
    try {
      list.add("5");
      fail("transformed list is addable");
    } catch (UnsupportedOperationException expected) {}
    list.remove(0);
    assertEquals(asList("2", "3", "4"), list);
    list.remove("3");
    assertEquals(asList("2", "4"), list);
    try {
      list.set(0, "5");
      fail("transformed list is setable");
    } catch (UnsupportedOperationException expected) {}
    list.clear();
    assertEquals(Collections.emptyList(), list);
  }

  public void testTransformViewRandomAccess() {
    List<Integer> fromList = Lists.newArrayList(SOME_LIST);
    List<String> toList = Lists.transform(fromList, SOME_FUNCTION);
    assertTransformView(fromList, toList);
  }

  public void testTransformViewSequential() {
    List<Integer> fromList = Lists.newLinkedList(SOME_SEQUENTIAL_LIST);
    List<String> toList = Lists.transform(fromList, SOME_FUNCTION);
    assertTransformView(fromList, toList);
  }

  private static void assertTransformView(List<Integer> fromList,
      List<String> toList) {
    /* fromList modifications reflected in toList */
    fromList.set(0, 5);
    assertEquals(asList("5", "2", "3", "4"), toList);
    fromList.add(6);
    assertEquals(asList("5", "2", "3", "4", "6"), toList);
    fromList.remove(Integer.valueOf(2));
    assertEquals(asList("5", "3", "4", "6"), toList);
    fromList.remove(2);
    assertEquals(asList("5", "3", "6"), toList);

    /* toList modifications reflected in fromList */
    toList.remove(2);
    assertEquals(asList(5, 3), fromList);
    toList.remove("5");
    assertEquals(asList(3), fromList);
    toList.clear();
    assertEquals(Collections.emptyList(), fromList);
  }

  public void testTransformRandomAccess() {
    List<String> list = Lists.transform(SOME_LIST, SOME_FUNCTION);
    assertTrue(list instanceof RandomAccess);
  }

  public void testTransformSequential() {
    List<String> list = Lists.transform(SOME_SEQUENTIAL_LIST, SOME_FUNCTION);
    assertThat(list).isNotInstanceOf(RandomAccess.class);
  }

  public void testTransformListIteratorRandomAccess() {
    List<Integer> fromList = Lists.newArrayList(SOME_LIST);
    List<String> list = Lists.transform(fromList, SOME_FUNCTION);
    assertTransformListIterator(list);
  }

  public void testTransformListIteratorSequential() {
    List<Integer> fromList = Lists.newLinkedList(SOME_SEQUENTIAL_LIST);
    List<String> list = Lists.transform(fromList, SOME_FUNCTION);
    assertTransformListIterator(list);
  }

  public void testTransformPreservesIOOBEsThrownByFunction() {
    try {
      Lists.transform(ImmutableList.of("foo", "bar"), new Function<String, String>() {
        @Override
        public String apply(String input) {
          throw new IndexOutOfBoundsException();
        }
      }).toArray();
      fail();
    } catch (IndexOutOfBoundsException expected) {
      // success
    }
  }

  private static void assertTransformListIterator(List<String> list) {
    ListIterator<String> iterator = list.listIterator(1);
    assertEquals(1, iterator.nextIndex());
    assertEquals("2", iterator.next());
    assertEquals("3", iterator.next());
    assertEquals("4", iterator.next());
    assertEquals(4, iterator.nextIndex());
    try {
      iterator.next();
      fail("did not detect end of list");
    } catch (NoSuchElementException expected) {}
    assertEquals(3, iterator.previousIndex());
    assertEquals("4", iterator.previous());
    assertEquals("3", iterator.previous());
    assertEquals("2", iterator.previous());
    assertTrue(iterator.hasPrevious());
    assertEquals("1", iterator.previous());
    assertFalse(iterator.hasPrevious());
    assertEquals(-1, iterator.previousIndex());
    try {
      iterator.previous();
      fail("did not detect beginning of list");
    } catch (NoSuchElementException expected) {}
    iterator.remove();
    assertEquals(asList("2", "3", "4"), list);
    assertFalse(list.isEmpty());

    // An UnsupportedOperationException or IllegalStateException may occur.
    try {
      iterator.add("1");
      fail("transformed list iterator is addable");
    } catch (UnsupportedOperationException expected) {
    } catch (IllegalStateException expected) {}
    try {
      iterator.set("1");
      fail("transformed list iterator is settable");
    } catch (UnsupportedOperationException expected) {
    } catch (IllegalStateException expected) {}
  }

  public void testTransformIteratorRandomAccess() {
    List<Integer> fromList = Lists.newArrayList(SOME_LIST);
    List<String> list = Lists.transform(fromList, SOME_FUNCTION);
    assertTransformIterator(list);
  }

  public void testTransformIteratorSequential() {
    List<Integer> fromList = Lists.newLinkedList(SOME_SEQUENTIAL_LIST);
    List<String> list = Lists.transform(fromList, SOME_FUNCTION);
    assertTransformIterator(list);
  }

  /**
   * We use this class to avoid the need to suppress generics checks with
   * easy mock.
   */
  private interface IntegerList extends List<Integer> {}

  /**
   * This test depends on the fact that {@code AbstractSequentialList.iterator}
   * transforms the {@code iterator()} call into a call on {@code
   * listIterator(int)}. This is fine because the behavior is clearly
   * documented so it's not expected to change.
   */
  @GwtIncompatible // EsayMock
  public void testTransformedSequentialIterationUsesBackingListIterationOnly() {
    List<Integer> randomAccessList = Lists.newArrayList(SOME_SEQUENTIAL_LIST);
    ListIterator<Integer> sampleListIterator =
        SOME_SEQUENTIAL_LIST.listIterator();
    List<Integer> listMock = EasyMock.createMock(IntegerList.class);
    EasyMock.expect(listMock.size()).andReturn(SOME_SEQUENTIAL_LIST.size());
    EasyMock.expect(listMock.listIterator(0)).andReturn(sampleListIterator);
    EasyMock.replay(listMock);
    List<String> transform = Lists.transform(listMock, SOME_FUNCTION);
    assertTrue(Iterables.elementsEqual(
        transform, Lists.transform(randomAccessList, SOME_FUNCTION)));
    EasyMock.verify(listMock);
  }

  private static void assertTransformIterator(List<String> list) {
    Iterator<String> iterator = list.iterator();
    assertTrue(iterator.hasNext());
    assertEquals("1", iterator.next());
    assertTrue(iterator.hasNext());
    assertEquals("2", iterator.next());
    assertTrue(iterator.hasNext());
    assertEquals("3", iterator.next());
    assertTrue(iterator.hasNext());
    assertEquals("4", iterator.next());
    assertFalse(iterator.hasNext());
    try {
      iterator.next();
      fail("did not detect end of list");
    } catch (NoSuchElementException expected) {}
    iterator.remove();
    assertEquals(asList("1", "2", "3"), list);
    assertFalse(iterator.hasNext());
  }

  public void testPartition_badSize() {
    List<Integer> source = Collections.singletonList(1);
    try {
      Lists.partition(source, 0);
      fail();
    } catch (IllegalArgumentException expected) {
    }
  }

  public void testPartition_empty() {
    List<Integer> source = Collections.emptyList();
    List<List partitions = Lists.partition(source, 1);
    assertTrue(partitions.isEmpty());
    assertEquals(0, partitions.size());
  }

  public void testPartition_1_1() {
    List<Integer> source = Collections.singletonList(1);
    List<List partitions = Lists.partition(source, 1);
    assertEquals(1, partitions.size());
    assertEquals(Collections.singletonList(1), partitions.get(0));
  }

  public void testPartition_1_2() {
    List<Integer> source = Collections.singletonList(1);
    List<List partitions = Lists.partition(source, 2);
    assertEquals(1, partitions.size());
    assertEquals(Collections.singletonList(1), partitions.get(0));
  }

  public void testPartition_2_1() {
    List<Integer> source = asList(1, 2);
    List<List partitions = Lists.partition(source, 1);
    assertEquals(2, partitions.size());
    assertEquals(Collections.singletonList(1), partitions.get(0));
    assertEquals(Collections.singletonList(2), partitions.get(1));
  }

  public void testPartition_3_2() {
    List<Integer> source = asList(1, 2, 3);
    List<List partitions = Lists.partition(source, 2);
    assertEquals(2, partitions.size());
    assertEquals(asList(1, 2), partitions.get(0));
    assertEquals(asList(3), partitions.get(1));
  }

  @GwtIncompatible // ArrayList.subList doesn't implement RandomAccess in GWT.
  public void testPartitionRandomAccessTrue() {
    List<Integer> source = asList(1, 2, 3);
    List<List partitions = Lists.partition(source, 2);

    assertTrue("partition should be RandomAccess, but not: "
        + partitions.getClass(),
        partitions instanceof RandomAccess);

    assertTrue("partition[0] should be RandomAccess, but not: "
        + partitions.get(0).getClass(),
        partitions.get(0) instanceof RandomAccess);

    assertTrue("partition[1] should be RandomAccess, but not: "
        + partitions.get(1).getClass(),
        partitions.get(1) instanceof RandomAccess);
  }

  public void testPartitionRandomAccessFalse() {
    List<Integer> source = Lists.newLinkedList(asList(1, 2, 3));
    List<List partitions = Lists.partition(source, 2);
    assertThat(partitions).isNotInstanceOf(RandomAccess.class);
    assertThat(partitions.get(0)).isNotInstanceOf(RandomAccess.class);
    assertThat(partitions.get(1)).isNotInstanceOf(RandomAccess.class);
  }

  // TODO: use the ListTestSuiteBuilder

  public void testPartition_view() {
    List<Integer> list = asList(1, 2, 3);
    List<List partitions = Lists.partition(list, 3);

    // Changes before the partition is retrieved are reflected
    list.set(0, 3);

    Iterator<List iterator = partitions.iterator();

    // Changes before the partition is retrieved are reflected
    list.set(1, 4);

    List<Integer> first = iterator.next();

    // Changes after are too (unlike Iterables.partition)
    list.set(2, 5);

    assertEquals(asList(3, 4, 5), first);

    // Changes to a sublist also write through to the original list
    first.set(1, 6);
    assertEquals(asList(3, 6, 5), list);
  }

  public void testPartitionSize_1() {
    List<Integer> list = asList(1, 2, 3);
    assertEquals(1, Lists.partition(list, Integer.MAX_VALUE).size());
    assertEquals(1, Lists.partition(list, Integer.MAX_VALUE - 1).size());
  }

  @GwtIncompatible // cannot do such a big explicit copy
  public void testPartitionSize_2() {
    assertEquals(2, Lists.partition(Collections.nCopies(0x40000001, 1), 0x40000000).size());
  }
}

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