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Commit 33de33e

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replace tests + docs
1 parent 02bdbe0 commit 33de33e

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‎README.md‎

Lines changed: 12 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -63,8 +63,10 @@ Replaces each entry's value with the result of invoking the given
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function on that entry until all entries have been processed or the
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function throws an exception
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* `default boolean replace(K key, V oldValue, V newValue)`
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* `default V replace(K key, V value)`
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* `default boolean replace(K key, V oldValue, V newValue)` - Replaces the
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entry for the specified key only if currently mapped to the specified value.
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* `default V replace(K key, V value)` - Replaces the entry for the
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specified key only if map contains key.
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* `default V computeIfAbsent(K key, Function<? super K, ? extends V> mappingFunction)`
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* `default V computeIfPresent(K key, BiFunction<? super K, ? super V, ? extends V> remappingFunction)`
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* `default V compute(K key, BiFunction<? super K, ? super V, ? extends V> remappingFunction)`
@@ -116,4 +118,12 @@ We provide tests for above mentioned methods.
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Map<String, Integer> counter = new HashMap<>();
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counter.replaceAll((k, v) -> ++v)
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```
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* replace value for given key only for specific oldValue
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```
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map.replace(1, "oldValue", "newValue");
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```
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* replace value for given key (map has to contain that key)
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```
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map.replace(1, "newValue");
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```

‎src/test/java/MapModifyingTest.java‎

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@@ -5,6 +5,7 @@
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import static org.hamcrest.CoreMatchers.is;
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import static org.hamcrest.MatcherAssert.assertThat;
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import static org.junit.Assert.assertNull;
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import static org.junit.Assert.assertTrue;
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/**
@@ -79,4 +80,80 @@ public void replaceAll() {
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assertThat(map.get(2), is("2-updated"));
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assertThat(map.get(3), is("3-updated"));
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}
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@Test
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public void replace_key_value_newValue_found() {
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Map<Integer, String> map = new HashMap<>();
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map.put(1, "old");
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map.replace(1, "old", "replaced");
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assertThat(map.get(1), is("replaced"));
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}
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@Test
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public void replace_key_value_newValue_notFound() {
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Map<Integer, String> map = new HashMap<>();
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map.put(1, "1");
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map.replace(1, "2", "replaced");
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assertThat(map.get(1), is("1"));
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}
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@Test
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public void replace_key_value_newValue_oldNull() {
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Map<Integer, String> map = new HashMap<>();
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map.put(1, null);
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map.replace(1, null, "replaced");
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assertThat(map.get(1), is("replaced"));
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}
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@Test
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public void replace_key_value_newValue_newNull() {
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Map<Integer, String> map = new HashMap<>();
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map.put(1, "1");
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map.replace(1, "1", null);
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assertThat(map.size(), is(1));
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assertNull(map.get(1));
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}
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@Test
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public void replace_key_value_found() {
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Map<Integer, String> map = new HashMap<>();
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map.put(1, "1");
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map.replace(1, "replaced");
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assertThat(map.get(1), is("replaced"));
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}
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@Test
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public void replace_key_value_notFound() {
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Map<Integer, String> map = new HashMap<>();
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map.replace(1, "replaced");
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assertTrue(map.isEmpty());
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}
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@Test
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public void replace_key_value_mappedToNull() {
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Map<Integer, String> map = new HashMap<>();
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map.put(1, null);
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map.replace(1, "replaced");
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assertThat(map.get(1), is("replaced"));
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}
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}

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