BAEL-1577 : hamcrest core matchers examples added as test cases (#3887)

guava/src/test/java/org/baeldung/hamcrest/HamcrestCommonCoreMatchersTest.java

@@ -0,0 +1,206 @@
+package org.baeldung.hamcrest;
+
+import org.assertj.core.util.Lists;
+import org.junit.Test;
+
+import java.util.List;
+
+import static org.hamcrest.CoreMatchers.*;
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.core.StringEndsWith.endsWith;
+import static org.hamcrest.core.StringStartsWith.startsWith;
+
+public class HamcrestCommonCoreMatchersTest {
+
+    @Test
+    public void givenTestInput_WhenUsingIsForMatch() {
+
+        // GIVEN
+        String testString = "hamcrest core";
+
+        // ASSERT
+        assertThat(testString, is("hamcrest core"));
+        assertThat(testString, is(equalTo("hamcrest core")));
+    }
+
+    @Test
+    public void givenTestInput_WhenUsingInstanceOfForClassTypeCheck(){
+
+        assertThat("hamcrest", is(instanceOf(String.class)));
+    }
+
+    @Test
+    public void givenTestInput_WhenUsingIsA_ThenAssertType(){
+
+        assertThat("hamcrest core", isA(String.class));
+    }
+
+    @Test
+    public void givenTestInput_WhenUsingEqualToMatcherForEquality(){
+
+        // GIVEN
+        String actualString = "Hamcrest Core";
+        List<String> actualList = Lists.newArrayList("hamcrest", "core");
+
+        // ASSERT
+        assertThat(actualString, is(equalTo("Hamcrest Core")));
+        assertThat(actualList, is(equalTo(Lists.newArrayList("hamcrest", "core"))));
+    }
+
+    @Test
+    public void givenTestInput_WhenUsingNotForMatch(){
+
+        // GIVEN
+        String testString = "hamcrest";
+
+        // ASSERT
+        assertThat(testString, not("hamcrest core"));
+        assertThat(testString, is(not(equalTo("hamcrest core"))));
+        assertThat(testString, is(not(instanceOf(Integer.class))));
+    }
+
+    @Test
+    public void givenTestInput_WhenUsingNullValueForNullCheck(){
+
+        // GIVEN
+        Integer nullObject = null;
+
+        // ASSERT
+        assertThat(nullObject, is(nullValue()));
+        assertThat(nullObject, is(nullValue(Integer.class)));
+    }
+
+    @Test
+    public void givenTestInput_WhenUsingNotNullValueForNotNullCheck(){
+
+        // GIVEN
+        Integer testNumber = 123;
+
+        // ASSERT
+        assertThat(testNumber, is(notNullValue()));
+        assertThat(testNumber, is(notNullValue(Integer.class)));
+    }
+
+    @Test
+    public void givenString_WhenStartsWith_ThenCorrect(){
+
+        // GIVEN
+        String testString = "hamcrest core";
+
+        // ASSERT
+        assertThat(testString, startsWith("hamcrest"));
+    }
+
+    @Test
+    public void givenString_WhenEndsWith_ThenCorrect(){
+
+        // GIVEN
+        String testString = "hamcrest core";
+
+        // ASSERT
+        assertThat(testString, endsWith("core"));
+    }
+
+    @Test
+    public void givenString_WhenContainsString_ThenCorrect(){
+
+        // GIVEN
+        String testString = "hamcrest core";
+
+        // ASSERT
+        assertThat(testString, containsString("co"));
+    }
+
+    @Test
+    public void givenTestInput_WhenUsingHasItemInCollection(){
+
+        // GIVEN
+        List<String> list = Lists.newArrayList("java", "spring", "baeldung");
+
+        // ASSERT
+        assertThat(list, hasItem("java"));
+        assertThat(list, hasItem(isA(String.class)));
+    }
+
+
+    @Test
+    public void givenTestInput_WhenUsingHasItemsInCollection(){
+
+        // GIVEN
+        List<String> list = Lists.newArrayList("java", "spring", "baeldung");
+
+        // ASSERT
+        assertThat(list, hasItems("java", "baeldung"));
+        assertThat(list, hasItems(isA(String.class), endsWith("ing")));
+    }
+
+    @Test
+    public void givenTestInput_WhenUsingAnyForClassType(){
+
+        assertThat("hamcrest", is(any(String.class)));
+        assertThat("hamcrest", is(any(Object.class)));
+    }
+
+    @Test
+    public void givenTestInput_WhenUsingAllOfForAllMatchers(){
+
+        // GIVEN
+        String testString = "Hamcrest Core";
+
+        // ASSERT
+        assertThat(testString, allOf(startsWith("Ham"), endsWith("ore"), containsString("Core")));
+    }
+
+    @Test
+    public void givenTestInput_WhenUsingAnyOfForAnyMatcher(){
+
+        // GIVEN
+        String testString = "Hamcrest Core";
+
+        // ASSERT
+        assertThat(testString, anyOf(startsWith("Ham"), containsString("baeldung")));
+    }
+
+    @Test
+    public void givenTestInput_WhenUsingBothForMatcher(){
+
+        // GIVEN
+        String testString = "Hamcrest Core Matchers";
+
+        // ASSERT
+        assertThat(testString, both(startsWith("Ham")).and(containsString("Core")));
+    }
+
+    @Test
+    public void givenTestInput_WhenUsingEitherForMatcher(){
+
+        // GIVEN
+        String testString = "Hamcrest Core Matchers";
+
+        // ASSERT
+        assertThat(testString, either(startsWith("Bael")).or(containsString("Core")));
+    }
+
+
+    @Test
+    public void givenTestInput_WhenUsingEveryItemForMatchInCollection(){
+
+        // GIVEN
+        List<String> testItems = Lists.newArrayList("Common", "Core", "Combinable");
+
+        // ASSERT
+        assertThat(testItems, everyItem(startsWith("Co")));
+    }
+
+    @Test
+    public void givenTwoTestInputs_WhenUsingSameInstanceForMatch(){
+
+        // GIVEN
+        String string1 = "hamcrest";
+        String string2 = string1;
+
+        // ASSERT
+        assertThat(string1, is(sameInstance(string2)));
+    }
+
+}