[rm-trailing-space] rm trailing whithspace

core-java-modules/core-java-string-operations-8/pom.xml

@@ -12,6 +12,14 @@
         <artifactId>core-java-modules</artifactId>
         <version>0.0.1-SNAPSHOT</version>
     </parent>
+    <dependencies>
+        <dependency>
+            <groupId>org.apache.commons</groupId>
+            <artifactId>commons-lang3</artifactId>
+            <version>${apache.commons.lang3.version}</version>
+        </dependency>
+
+    </dependencies>
 
     <build>
         <plugins>
@@ -29,6 +37,7 @@
     <properties>
         <maven.compiler.source>11</maven.compiler.source>
         <maven.compiler.target>11</maven.compiler.target>
+        <apache.commons.lang3.version>3.14.0</apache.commons.lang3.version>
     </properties>
 
 </project>

core-java-modules/core-java-string-operations-8/src/test/java/com/baeldung/removetrailingspaces/RemoveTrailingSpaceOrWhitespaceUnitTest.java

@@ -0,0 +1,38 @@
+package com.baeldung.removetrailingspaces;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import org.apache.commons.lang3.StringUtils;
+import org.junit.jupiter.api.Test;
+
+public class RemoveTrailingSpaceOrWhitespaceUnitTest {
+
+    private final static String INPUT = "  a b c d e \t  ";
+
+    @Test
+    void whenUsingTrim_thenBothLeadingAndTrailingWhitespaceAreRemoved() {
+        String result = INPUT.trim();
+        assertEquals("a b c d e", result);
+    }
+
+    @Test
+    void whenUsingReplaceAll_thenGetExpectedResult() {
+        String result1 = INPUT.replaceAll(" +$", "");
+        assertEquals("  a b c d e \t", result1);
+
+        String result2 = INPUT.replaceAll("\\s+$", "");
+        assertEquals("  a b c d e", result2);
+    }
+
+    @Test
+    void whenUsingStripTrailing_thenAllTrailingWhitespaceRemoved() {
+        String result = INPUT.stripTrailing();
+        assertEquals("  a b c d e", result);
+    }
+
+    @Test
+    void whenUsingStringUtilsStripEnd_thenTrailingSpaceRemoved() {
+        String result = StringUtils.stripEnd(INPUT, " ");
+        assertEquals("  a b c d e \t", result);
+    }
+}