001/*
002 * Copyright (C) 2008 The Guava Authors
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 * http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package com.google.common.collect.testing.testers;
018
019import static com.google.common.collect.testing.features.CollectionFeature.ALLOWS_NULL_VALUES;
020import static com.google.common.collect.testing.features.CollectionSize.ZERO;
021import static com.google.common.collect.testing.features.ListFeature.SUPPORTS_SET;
022
023import com.google.common.annotations.GwtCompatible;
024import com.google.common.annotations.GwtIncompatible;
025import com.google.common.collect.testing.Helpers;
026import com.google.common.collect.testing.features.CollectionFeature;
027import com.google.common.collect.testing.features.CollectionSize;
028import com.google.common.collect.testing.features.ListFeature;
029import java.lang.reflect.Method;
030import org.junit.Ignore;
031
032/**
033 * A generic JUnit test which tests {@code set()} operations on a list. Can't be invoked directly;
034 * please see {@link com.google.common.collect.testing.ListTestSuiteBuilder}.
035 *
036 * @author George van den Driessche
037 */
038@GwtCompatible(emulated = true)
039@Ignore // Affects only Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.
040public class ListSetTester<E> extends AbstractListTester<E> {
041  @ListFeature.Require(SUPPORTS_SET)
042  @CollectionSize.Require(absent = ZERO)
043  public void testSet() {
044    doTestSet(e3());
045  }
046
047  @CollectionSize.Require(absent = ZERO)
048  @CollectionFeature.Require(ALLOWS_NULL_VALUES)
049  @ListFeature.Require(SUPPORTS_SET)
050  public void testSet_null() {
051    doTestSet(null);
052  }
053
054  @CollectionSize.Require(absent = ZERO)
055  @CollectionFeature.Require(ALLOWS_NULL_VALUES)
056  @ListFeature.Require(SUPPORTS_SET)
057  public void testSet_replacingNull() {
058    E[] elements = createSamplesArray();
059    int i = aValidIndex();
060    elements[i] = null;
061    collection = getSubjectGenerator().create(elements);
062
063    doTestSet(e3());
064  }
065
066  private void doTestSet(E newValue) {
067    int index = aValidIndex();
068    E initialValue = getList().get(index);
069    assertEquals(
070        "set(i, x) should return the old element at position i.",
071        initialValue,
072        getList().set(index, newValue));
073    assertEquals("After set(i, x), get(i) should return x", newValue, getList().get(index));
074    assertEquals("set() should not change the size of a list.", getNumElements(), getList().size());
075  }
076
077  @ListFeature.Require(SUPPORTS_SET)
078  public void testSet_indexTooLow() {
079    try {
080      getList().set(-1, e3());
081      fail("set(-1) should throw IndexOutOfBoundsException");
082    } catch (IndexOutOfBoundsException expected) {
083    }
084    expectUnchanged();
085  }
086
087  @ListFeature.Require(SUPPORTS_SET)
088  public void testSet_indexTooHigh() {
089    int index = getNumElements();
090    try {
091      getList().set(index, e3());
092      fail("set(size) should throw IndexOutOfBoundsException");
093    } catch (IndexOutOfBoundsException expected) {
094    }
095    expectUnchanged();
096  }
097
098  @CollectionSize.Require(absent = ZERO)
099  @ListFeature.Require(absent = SUPPORTS_SET)
100  public void testSet_unsupported() {
101    try {
102      getList().set(aValidIndex(), e3());
103      fail("set() should throw UnsupportedOperationException");
104    } catch (UnsupportedOperationException expected) {
105    }
106    expectUnchanged();
107  }
108
109  @CollectionSize.Require(ZERO)
110  @ListFeature.Require(absent = SUPPORTS_SET)
111  public void testSet_unsupportedByEmptyList() {
112    try {
113      getList().set(0, e3());
114      fail("set() should throw UnsupportedOperationException or IndexOutOfBoundsException");
115    } catch (UnsupportedOperationException | IndexOutOfBoundsException tolerated) {
116    }
117    expectUnchanged();
118  }
119
120  @CollectionSize.Require(absent = ZERO)
121  @ListFeature.Require(SUPPORTS_SET)
122  @CollectionFeature.Require(absent = ALLOWS_NULL_VALUES)
123  public void testSet_nullUnsupported() {
124    try {
125      getList().set(aValidIndex(), null);
126      fail("set(null) should throw NullPointerException");
127    } catch (NullPointerException expected) {
128    }
129    expectUnchanged();
130  }
131
132  private int aValidIndex() {
133    return getList().size() / 2;
134  }
135
136  /**
137   * Returns the {@link java.lang.reflect.Method} instance for {@link #testSet_null()} so that tests
138   * of {@link java.util.Collections#checkedCollection(java.util.Collection, Class)} can suppress it
139   * with {@code FeatureSpecificTestSuiteBuilder.suppressing()} until <a
140   * href="http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6409434">Sun bug 6409434</a> is fixed.
141   * It's unclear whether nulls were to be permitted or forbidden, but presumably the eventual fix
142   * will be to permit them, as it seems more likely that code would depend on that behavior than on
143   * the other. Thus, we say the bug is in set(), which fails to support null.
144   */
145  @GwtIncompatible // reflection
146  public static Method getSetNullSupportedMethod() {
147    return Helpers.getMethod(ListSetTester.class, "testSet_null");
148  }
149}