diff --git a/atomikos/pom.xml b/atomikos/pom.xml
index 881adae074..d680a3ca77 100644
--- a/atomikos/pom.xml
+++ b/atomikos/pom.xml
@@ -41,7 +41,7 @@
 		<dependency>
 			<groupId>org.springframework.data</groupId>
 			<artifactId>spring-data-jpa</artifactId>
-			<version>1.11.23.RELEASE</version>
+			<version>${spring-data-jpa.version}</version>
 		</dependency>
 		<dependency>
 			<groupId>org.springframework</groupId>
@@ -64,49 +64,49 @@
 		<dependency>
 			<groupId>org.apache.activemq</groupId>
 			<artifactId>activemq-core</artifactId>
-			<version>5.7.0</version>
+			<version>${activemq-core.version}</version>
 		</dependency>
 		<dependency>
 			<groupId>org.apache.derby</groupId>
 			<artifactId>derby</artifactId>
-			<version>10.8.1.2</version>
+			<version>${derby.version}</version>
 		</dependency>
 		<dependency>
 			<groupId>junit</groupId>
 			<artifactId>junit</artifactId>
-			<version>4.12</version>
+			<version>${junit.version}</version>
 			<scope>test</scope>
 		</dependency>
 		<!-- the JTA API -->
 		<dependency>
 			<groupId>javax.transaction</groupId>
 			<artifactId>jta</artifactId>
-			<version>1.1</version>
+			<version>${jta.version}</version>
 		</dependency>
 		<dependency>
 			<groupId>org.apache.geronimo.specs</groupId>
 			<artifactId>geronimo-jta_1.0.1B_spec</artifactId>
-			<version>1.0</version>
+			<version>${geronimo.version}</version>
 		</dependency>
 		<dependency>
 			<groupId>javax.validation</groupId>
 			<artifactId>validation-api</artifactId>
-			<version>2.0.1.Final</version>
+			<version>${validation-api.version}</version>
 		</dependency>
 		<dependency>
 			<groupId>org.hibernate.validator</groupId>
 			<artifactId>hibernate-validator</artifactId>
-			<version>6.1.2.Final</version>
+			<version>${hibernate-validator.version}</version>
 		</dependency>
 		<dependency>
 			<groupId>javax.el</groupId>
 			<artifactId>javax.el-api</artifactId>
-			<version>3.0.0</version>
+			<version>${javax.el-api.version}</version>
 		</dependency>
 		<dependency>
 			<groupId>org.glassfish.web</groupId>
 			<artifactId>javax.el</artifactId>
-			<version>2.2.4</version>
+			<version>${javax.el.version}</version>
 		</dependency>
 	</dependencies>
 
@@ -114,6 +114,15 @@
 		<atomikos-version>5.0.6</atomikos-version>
 		<spring-version>5.1.6.RELEASE</spring-version>
 		<hibernate.version>5.4.3.Final</hibernate.version>
+		<spring-data-jpa.version>1.11.23.RELEASE</spring-data-jpa.version>
+		<activemq-core.version>5.7.0</activemq-core.version>
+		<derby.version>10.8.1.2</derby.version>
+		<jta.version>1.1</jta.version>
+		<geronimo.version>1.0</geronimo.version>
+		<validation-api.version>2.0.1.Final</validation-api.version>
+		<hibernate-validator.version>6.1.2.Final</hibernate-validator.version>
+		<javax.el-api.version>3.0.0</javax.el-api.version>
+		<javax.el.version>2.2.4</javax.el.version>
 	</properties>
 
 </project>
\ No newline at end of file
diff --git a/core-groovy-2/determine-datatype/pom.xml b/core-groovy-2/determine-datatype/pom.xml
index 0bcef4e5d8..e03cb58ead 100644
--- a/core-groovy-2/determine-datatype/pom.xml
+++ b/core-groovy-2/determine-datatype/pom.xml
@@ -34,7 +34,11 @@
         <dependency>
             <groupId>org.junit</groupId>
             <artifactId>junit5-engine</artifactId>
-            <version>5.0.0-ALPHA</version>
+            <version>${junit5.version}</version>
         </dependency>
     </dependencies>
+
+    <properties>
+        <junit5.version>5.0.0-ALPHA</junit5.version>
+    </properties>
 </project>
\ No newline at end of file
diff --git a/core-java-modules/core-java-concurrency-2/pom.xml b/core-java-modules/core-java-concurrency-2/pom.xml
index 75fd3890b3..253537bc2b 100644
--- a/core-java-modules/core-java-concurrency-2/pom.xml
+++ b/core-java-modules/core-java-concurrency-2/pom.xml
@@ -19,31 +19,31 @@
         <dependency>
             <groupId>junit</groupId>
             <artifactId>junit</artifactId>
-            <version>4.13</version>
+            <version>${junit.version}</version>
             <scope>test</scope>
         </dependency>
         <dependency>
             <groupId>com.googlecode.thread-weaver</groupId>
             <artifactId>threadweaver</artifactId>
-            <version>0.2</version>
+            <version>${threadweaver.version}</version>
             <scope>test</scope>
         </dependency>
         <dependency>
             <groupId>com.google.code.tempus-fugit</groupId>
             <artifactId>tempus-fugit</artifactId>
-            <version>1.1</version>
+            <version>${tempus-fugit.version}</version>
             <scope>test</scope>
         </dependency>
         <dependency>
             <groupId>com.googlecode.multithreadedtc</groupId>
             <artifactId>multithreadedtc</artifactId>
-            <version>1.01</version>
+            <version>${multithreadedtc.version}</version>
             <scope>test</scope>
         </dependency>
         <dependency>
             <groupId>org.openjdk.jcstress</groupId>
             <artifactId>jcstress-core</artifactId>
-            <version>0.5</version>
+            <version>${jcstress-core.version}</version>
         </dependency>
     </dependencies>
 
@@ -63,8 +63,8 @@
                 <version>3.1</version>
                 <configuration>
                     <compilerVersion>${javac.target}</compilerVersion>
-                    <source>${javac.target}</source>
-                    <target>${javac.target}</target>
+                    <source>${java.version}</source>
+                    <target>${java.version}</target>
                 </configuration>
             </plugin>
 
@@ -99,7 +99,11 @@
     </build>
     
     <properties>
-        <javac.target>1.8</javac.target>
+        <junit.version>4.13</junit.version>
+        <threadweaver.version>0.2</threadweaver.version>
+        <tempus-fugit.version>1.1</tempus-fugit.version>
+        <multithreadedtc.version>1.01</multithreadedtc.version>
+        <jcstress-core.version>0.5</jcstress-core.version>
     </properties>
 
 </project>
diff --git a/core-java-modules/core-java-io-2/pom.xml b/core-java-modules/core-java-io-2/pom.xml
index bdc2ee37f5..c0aae2b1ce 100644
--- a/core-java-modules/core-java-io-2/pom.xml
+++ b/core-java-modules/core-java-io-2/pom.xml
@@ -50,7 +50,7 @@
         <dependency>
             <groupId>com.github.tomakehurst</groupId>
             <artifactId>wiremock</artifactId>
-            <version>2.26.3</version>
+            <version>${wiremock.version}</version>
             <scope>test</scope>
         </dependency>
 
@@ -80,6 +80,7 @@
     <properties>
         <assertj.version>3.6.1</assertj.version>
         <maven-javadoc-plugin.version>3.0.0-M1</maven-javadoc-plugin.version>
+        <wiremock.version>2.26.3</wiremock.version>
     </properties>
 
 </project>
\ No newline at end of file
diff --git a/core-java-modules/core-java-io-conversions-2/pom.xml b/core-java-modules/core-java-io-conversions-2/pom.xml
index 46bce7988b..e9cf3f55d1 100644
--- a/core-java-modules/core-java-io-conversions-2/pom.xml
+++ b/core-java-modules/core-java-io-conversions-2/pom.xml
@@ -24,7 +24,7 @@
         <dependency>
             <groupId>org.json</groupId>
             <artifactId>json</artifactId>
-            <version>20200518</version>
+            <version>${json.version}</version>
         </dependency>
     </dependencies>
 
@@ -38,4 +38,8 @@
         </resources>
     </build>
 
+    <properties>
+        <json.version>20200518</json.version>
+    </properties>
+
 </project>
\ No newline at end of file
diff --git a/core-java-modules/core-java-regex/pom.xml b/core-java-modules/core-java-regex/pom.xml
index 9e2d91d5d9..f26218877c 100644
--- a/core-java-modules/core-java-regex/pom.xml
+++ b/core-java-modules/core-java-regex/pom.xml
@@ -29,7 +29,7 @@
         <dependency>
             <groupId>org.assertj</groupId>
             <artifactId>assertj-core</artifactId>
-            <version>3.15.0</version>
+            <version>${assertj-core.version}</version>
             <scope>test</scope>
         </dependency>
     </dependencies>
@@ -44,4 +44,8 @@
         </resources>
     </build>
 
+    <properties>
+        <assertj-core.version>3.15.0</assertj-core.version>
+    </properties>
+
 </project>
diff --git a/core-java-modules/core-java-security-2/pom.xml b/core-java-modules/core-java-security-2/pom.xml
index 85aa3869b3..890b4147ca 100644
--- a/core-java-modules/core-java-security-2/pom.xml
+++ b/core-java-modules/core-java-security-2/pom.xml
@@ -41,7 +41,7 @@
         <dependency>
             <groupId>javax.xml.bind</groupId>
             <artifactId>jaxb-api</artifactId>
-            <version>2.3.1</version>
+            <version>${jaxb-api.version}</version>
         </dependency>
 
 
@@ -54,6 +54,7 @@
 
         <!-- testing -->
         <assertj-core.version>3.10.0</assertj-core.version>
+        <jaxb-api.version>2.3.1</jaxb-api.version>
     </properties>
 
 </project>
diff --git a/image-processing/pom.xml b/image-processing/pom.xml
index 806cccf351..8fe161337c 100644
--- a/image-processing/pom.xml
+++ b/image-processing/pom.xml
@@ -38,7 +38,7 @@
         <dependency>
             <groupId>org.openpnp</groupId>
             <artifactId>opencv</artifactId>
-            <version>3.4.2-0</version>
+            <version>${opencv.version}</version>
         </dependency>
         <dependency>
             <groupId>com.twelvemonkeys.imageio</groupId>
@@ -68,6 +68,7 @@
         <imageio.version>3.3.2</imageio.version>
         <tess4j.version>4.5.1</tess4j.version>
         <tesseract-platform.version>4.1.0-1.5.2</tesseract-platform.version>
+        <opencv.version>3.4.2-0</opencv.version>
     </properties>
 
 </project>
\ No newline at end of file
diff --git a/jackson-modules/jackson-conversions-2/pom.xml b/jackson-modules/jackson-conversions-2/pom.xml
index 43c9d1478b..992cff30b2 100644
--- a/jackson-modules/jackson-conversions-2/pom.xml
+++ b/jackson-modules/jackson-conversions-2/pom.xml
@@ -23,7 +23,7 @@
         <dependency>
             <groupId>com.fasterxml.jackson.datatype</groupId>
             <artifactId>jackson-datatype-jsr310</artifactId>
-            <version>2.9.8</version>
+            <version>${jackson-datatype.version}</version>
         </dependency>
         <!-- CSV -->
         <dependency>
@@ -51,6 +51,7 @@
 
     <properties>
         <assertj.version>3.11.0</assertj.version>
+        <jackson-datatype.version>2.9.8</jackson-datatype.version>
     </properties>
 
 </project>
diff --git a/json-2/pom.xml b/json-2/pom.xml
index e0295af59b..d674d6f86d 100644
--- a/json-2/pom.xml
+++ b/json-2/pom.xml
@@ -47,12 +47,13 @@
         <dependency>
             <groupId>org.apache.commons</groupId>
             <artifactId>commons-lang3</artifactId>
-            <version>3.9</version>
+            <version>${commons-lang3.version}</version>
         </dependency>
     </dependencies>
     <properties>
         <jsoniter.version>0.9.23</jsoniter.version>
         <assertj-core.version>3.11.1</assertj-core.version>
         <moshi.version>1.9.2</moshi.version>
+        <commons-lang3.version>3.9</commons-lang3.version>
     </properties>
 </project>
diff --git a/kotlin-libraries/pom.xml b/kotlin-libraries/pom.xml
index 0d6e589377..908a545ae3 100644
--- a/kotlin-libraries/pom.xml
+++ b/kotlin-libraries/pom.xml
@@ -151,7 +151,6 @@
     </dependencies>
 
     <properties>
-        <junit.version>4.12</junit.version>
         <mockito-kotlin.version>1.5.0</mockito-kotlin.version>
         <kodein.version>4.1.0</kodein.version>
         <klaxon.version>3.0.4</klaxon.version>
diff --git a/kotlin-quasar/pom.xml b/kotlin-quasar/pom.xml
index ec37fa8059..59553f422e 100644
--- a/kotlin-quasar/pom.xml
+++ b/kotlin-quasar/pom.xml
@@ -148,7 +148,6 @@
         <dependency.plugin.version>3.1.1</dependency.plugin.version> 
         <surefire.plugin.version>2.22.1</surefire.plugin.version>
         <exec.plugin.version>1.3.2</exec.plugin.version>
-        <junit.version>4.12</junit.version>
     </properties>
 
 </project>
diff --git a/libraries-3/pom.xml b/libraries-3/pom.xml
index 5334bfba70..2f6e9fa747 100644
--- a/libraries-3/pom.xml
+++ b/libraries-3/pom.xml
@@ -73,19 +73,19 @@
           <dependency>
             <groupId>com.uber.nullaway</groupId>
             <artifactId>nullaway</artifactId>
-            <version>0.3.0</version>
+            <version>${nullaway.version}</version>
         </dependency>
         <dependency>
             <groupId>org.codehaus.plexus</groupId>
             <artifactId>plexus-compiler-javac-errorprone</artifactId>
-            <version>2.8</version>
+            <version>${plexus-compiler.version}</version>
         </dependency>
         <!-- override plexus-compiler-javac-errorprone's dependency on
              Error Prone with the latest version -->
         <dependency>
             <groupId>com.google.errorprone</groupId>
             <artifactId>error_prone_core</artifactId>
-            <version>2.1.3</version>
+            <version>${errorprone.version}</version>
         </dependency>
     </dependencies>
 
@@ -230,5 +230,8 @@
         <httpclient.version>4.5.12</httpclient.version>
         <velocity-engine-core.version>2.2</velocity-engine-core.version>
         <exec-maven-plugin.version>1.6.0</exec-maven-plugin.version>
+        <nullaway.version>0.3.0</nullaway.version>
+        <plexus-compiler.version>2.8</plexus-compiler.version>
+        <errorprone.version>2.1.3</errorprone.version>
     </properties>
 </project>
diff --git a/libraries-4/pom.xml b/libraries-4/pom.xml
index f26e7fc055..d7f6a44985 100644
--- a/libraries-4/pom.xml
+++ b/libraries-4/pom.xml
@@ -91,7 +91,7 @@
         <dependency>
             <groupId>org.glassfish.web</groupId>
             <artifactId>javax.el</artifactId>
-            <version>2.2.4</version>
+            <version>${glassfish.web.version}</version>
         </dependency>
     </dependencies>
 
@@ -111,6 +111,7 @@
         <awaitility.version>3.0.0</awaitility.version>
         <streamex.version>0.6.5</streamex.version>
         <javax.el.version>3.0.0</javax.el.version>
+        <glassfish.web.version>2.2.4</glassfish.web.version>
     </properties>
 
 </project>
\ No newline at end of file
diff --git a/libraries-concurrency/pom.xml b/libraries-concurrency/pom.xml
index e1307408b0..b7dc5187b1 100644
--- a/libraries-concurrency/pom.xml
+++ b/libraries-concurrency/pom.xml
@@ -16,17 +16,17 @@
         <dependency>
             <groupId>co.paralleluniverse</groupId>
             <artifactId>quasar-core</artifactId>
-            <version>0.8.0</version>
+            <version>${quasar.version}</version>
         </dependency>
         <dependency>
             <groupId>co.paralleluniverse</groupId>
             <artifactId>quasar-actors</artifactId>
-            <version>0.8.0</version>
+            <version>${quasar.version}</version>
         </dependency>
         <dependency>
             <groupId>co.paralleluniverse</groupId>
             <artifactId>quasar-reactive-streams</artifactId>
-            <version>0.8.0</version>
+            <version>${quasar.version}</version>
         </dependency>
     </dependencies>
 
@@ -78,4 +78,8 @@
             </plugin>
         </plugins>
     </build>
+
+    <properties>
+        <quasar.version>0.8.0</quasar.version>
+    </properties>
 </project>
\ No newline at end of file
diff --git a/micronaut/pom.xml b/micronaut/pom.xml
index 2cb05cc1b9..d6df6a0347 100644
--- a/micronaut/pom.xml
+++ b/micronaut/pom.xml
@@ -144,7 +144,6 @@
         <jdk.version>1.8</jdk.version>
         <annotation.api.version>1.3.2</annotation.api.version>
         <lombok.version>1.2.3</lombok.version>
-        <junit.version>4.12</junit.version>
         <reactor.version>3.1.6.RELEASE</reactor.version>
         <compiler.plugin.version>3.7.0</compiler.plugin.version>
         <exec.plugin.version>1.6.0</exec.plugin.version>
diff --git a/parent-boot-2/pom.xml b/parent-boot-2/pom.xml
index c7bb11b1d5..ab5424bfaf 100644
--- a/parent-boot-2/pom.xml
+++ b/parent-boot-2/pom.xml
@@ -82,6 +82,7 @@
         <!-- plugins -->
         <thin.version>1.0.22.RELEASE</thin.version>
         <spring-boot.version>2.2.6.RELEASE</spring-boot.version>
+        <aspectjweaver.version>1.9.1</aspectjweaver.version>
     </properties>
 
 </project>
diff --git a/parent-java/pom.xml b/parent-java/pom.xml
index baad9fecf4..f56ffbd7f7 100644
--- a/parent-java/pom.xml
+++ b/parent-java/pom.xml
@@ -46,7 +46,6 @@
         <commons.io.version>2.6</commons.io.version>
         <jmh.version>1.19</jmh.version>
         <modelmapper.version>2.3.7</modelmapper.version>
-        <junit.version>4.12</junit.version>
         <hamcrest.version>2.2</hamcrest.version>
     </properties>
 
diff --git a/parent-spring-5/pom.xml b/parent-spring-5/pom.xml
index c75655ebc8..949e40b021 100644
--- a/parent-spring-5/pom.xml
+++ b/parent-spring-5/pom.xml
@@ -33,6 +33,7 @@
     <properties>
         <spring.version>5.2.5.RELEASE</spring.version>
         <spring-security.version>5.2.3.RELEASE</spring-security.version>
+        <spring-boot-starter-test.version>1.5.10.RELEASE</spring-boot-starter-test.version>
     </properties>
 
 </project>
\ No newline at end of file
diff --git a/patterns/cqrs-es/pom.xml b/patterns/cqrs-es/pom.xml
index 3c54038837..67665a2d32 100644
--- a/patterns/cqrs-es/pom.xml
+++ b/patterns/cqrs-es/pom.xml
@@ -13,17 +13,19 @@
     <properties>
         <maven.compiler.source>1.8</maven.compiler.source>
         <maven.compiler.target>1.8</maven.compiler.target>
+        <junit.version>4.13</junit.version>
+        <lombok.version>1.18.12</lombok.version>
     </properties>
     <dependencies>
         <dependency>
             <groupId>org.projectlombok</groupId>
             <artifactId>lombok</artifactId>
-            <version>1.18.12</version>
+            <version>${lombok.version}</version>
         </dependency>
         <dependency>
             <groupId>junit</groupId>
             <artifactId>junit</artifactId>
-            <version>4.13</version>
+            <version>${junit.version}</version>
             <scope>test</scope>
         </dependency>
     </dependencies>
diff --git a/pdf/pom.xml b/pdf/pom.xml
index 463c88948d..7d7754ee73 100644
--- a/pdf/pom.xml
+++ b/pdf/pom.xml
@@ -63,12 +63,12 @@
         <dependency>
             <groupId>org.thymeleaf</groupId>
             <artifactId>thymeleaf</artifactId>
-            <version>3.0.11.RELEASE</version>
+            <version>${thymeleaf.version}</version>
         </dependency>
         <dependency>
             <groupId>org.xhtmlrenderer</groupId>
             <artifactId>flying-saucer-pdf</artifactId>
-            <version>9.1.20</version>
+            <version>${flying-saucer-pdf.version}</version>
         </dependency>
     </dependencies>
 
@@ -90,6 +90,8 @@
         <poi-scratchpad.version>3.15</poi-scratchpad.version>
         <batik-transcoder.version>1.8</batik-transcoder.version>
         <poi-ooxml.version>3.15</poi-ooxml.version>
+        <thymeleaf.version>3.0.11.RELEASE</thymeleaf.version>
+        <flying-saucer-pdf.version>9.1.20</flying-saucer-pdf.version>
     </properties>
 
 </project>
diff --git a/persistence-modules/redis/pom.xml b/persistence-modules/redis/pom.xml
index dab7fc5654..b8f76c09c4 100644
--- a/persistence-modules/redis/pom.xml
+++ b/persistence-modules/redis/pom.xml
@@ -33,7 +33,7 @@
         <dependency>
             <groupId>redis.clients</groupId>
             <artifactId>jedis</artifactId>
-            <version>3.3.0</version>
+            <version>${redisson.version}</version>
         </dependency>
         <dependency>
             <groupId>com.github.kstyrc</groupId>
diff --git a/persistence-modules/spring-data-jpa-5/pom.xml b/persistence-modules/spring-data-jpa-5/pom.xml
index 6a5cdc86c2..f09c83ab11 100644
--- a/persistence-modules/spring-data-jpa-5/pom.xml
+++ b/persistence-modules/spring-data-jpa-5/pom.xml
@@ -42,7 +42,7 @@
         <dependency>
             <groupId>org.mapstruct</groupId>
             <artifactId>mapstruct-jdk8</artifactId>
-            <version>1.3.1.Final</version>
+            <version>${mapstruct.version}</version>
             <scope>provided</scope>
         </dependency>
       
@@ -68,4 +68,14 @@
             </plugin>
         </plugins>
     </build>
+
+    <properties>
+        <spring-boot-version>2.1.9.RELEASE</spring-boot-version>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+        <start-class>com.baeldung.springdatageode.app.ClientCacheApp</start-class>
+        <spring-geode-starter-version>1.1.1.RELEASE</spring-geode-starter-version>
+        <spring.boot.starter.version>2.1.9.RELEASE</spring.boot.starter.version>
+        <mapstruct.version>1.3.1.Final</mapstruct.version>
+    </properties>
+
 </project>
diff --git a/persistence-modules/spring-data-mongodb/pom.xml b/persistence-modules/spring-data-mongodb/pom.xml
index 3f7c1cbcb9..fb80ba33ac 100644
--- a/persistence-modules/spring-data-mongodb/pom.xml
+++ b/persistence-modules/spring-data-mongodb/pom.xml
@@ -22,7 +22,7 @@
         <dependency>
             <groupId>org.springframework.data</groupId>
             <artifactId>spring-data-releasetrain</artifactId>
-            <version>Lovelace-SR9</version>
+            <version>${spring-releasetrain}</version>
             <type>pom</type>
         </dependency>
 
@@ -101,6 +101,7 @@
         <mysema.maven.version>1.1.3</mysema.maven.version>
         <mongodb-reactivestreams.version>1.9.2</mongodb-reactivestreams.version>
         <projectreactor.version>3.2.0.RELEASE</projectreactor.version>
+        <spring-releasetrain>Lovelace-SR9</spring-releasetrain>
     </properties>
 
 </project>
diff --git a/spring-5-mvc/pom.xml b/spring-5-mvc/pom.xml
index 945ddef5e1..fd9868ad66 100644
--- a/spring-5-mvc/pom.xml
+++ b/spring-5-mvc/pom.xml
@@ -87,7 +87,7 @@
         <dependency>
             <groupId>com.github.javafaker</groupId>
             <artifactId>javafaker</artifactId>
-            <version>0.18</version>
+            <version>${javafaker.version}</version>
         </dependency>
         <dependency>
             <groupId>org.apache.httpcomponents</groupId>
@@ -177,6 +177,7 @@
         <kotlin.version>1.2.71</kotlin.version> <!-- Same as spring-boot-dependencies:2.1.7.RELEASE -->
         <httpclient.version>4.5.8</httpclient.version>
         <start-class>com.baeldung.Spring5Application</start-class>
+        <javafaker.version>0.18</javafaker.version>
     </properties>
 
 </project>
diff --git a/spring-5-reactive-client/pom.xml b/spring-5-reactive-client/pom.xml
index cc728398f3..0b5efd1a47 100644
--- a/spring-5-reactive-client/pom.xml
+++ b/spring-5-reactive-client/pom.xml
@@ -60,12 +60,12 @@
         <dependency>
             <groupId>com.squareup.okhttp3</groupId>
             <artifactId>okhttp</artifactId>
-            <version>4.0.1</version>
+            <version>${okhttp.version}</version>
         </dependency>
         <dependency>
             <groupId>com.squareup.okhttp3</groupId>
             <artifactId>mockwebserver</artifactId>
-            <version>4.0.1</version>
+            <version>${okhttp.version}</version>
             <scope>test</scope>
         </dependency>
 
@@ -171,6 +171,7 @@
         <geronimo-json_1.1_spec.version>1.0</geronimo-json_1.1_spec.version>
         <commons-collections4.version>4.1</commons-collections4.version>
         <jetty-reactive-httpclient.version>1.0.3</jetty-reactive-httpclient.version>
+        <okhttp.version>4.0.1</okhttp.version>
     </properties>
 
 </project>
diff --git a/spring-boot-modules/spring-boot-angular/pom.xml b/spring-boot-modules/spring-boot-angular/pom.xml
index 5cfc530100..e8082656ad 100644
--- a/spring-boot-modules/spring-boot-angular/pom.xml
+++ b/spring-boot-modules/spring-boot-angular/pom.xml
@@ -27,7 +27,7 @@
         <dependency>
             <groupId>com.h2database</groupId>
             <artifactId>h2</artifactId>
-            <version>1.4.197</version>
+            <version>${h2.version}</version>
             <scope>runtime</scope>
         </dependency>
         <dependency>
diff --git a/spring-boot-modules/spring-boot-annotations/pom.xml b/spring-boot-modules/spring-boot-annotations/pom.xml
index 59de83b4e5..da2c46ca92 100644
--- a/spring-boot-modules/spring-boot-annotations/pom.xml
+++ b/spring-boot-modules/spring-boot-annotations/pom.xml
@@ -17,7 +17,7 @@
         <dependency>
             <groupId>org.aspectj</groupId>
             <artifactId>aspectjweaver</artifactId>
-            <version>1.9.1</version>
+            <version>${aspectjweaver.version}</version>
         </dependency>
 
         <dependency>
diff --git a/spring-boot-modules/spring-boot-exceptions/pom.xml b/spring-boot-modules/spring-boot-exceptions/pom.xml
index f69beccf5d..6ef7e66770 100644
--- a/spring-boot-modules/spring-boot-exceptions/pom.xml
+++ b/spring-boot-modules/spring-boot-exceptions/pom.xml
@@ -18,7 +18,7 @@
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter</artifactId>
-            <version>2.2.3.RELEASE</version>
+            <version>${spring-boot.version}</version>
         </dependency>
     </dependencies>
 
@@ -92,5 +92,6 @@
     <properties>
         <!-- The main class to start by executing java -jar -->
         <start-class>com.baeldung.intro.App</start-class>
+        <spring-boot.version>2.2.3.RELEASE</spring-boot.version>
     </properties>
 </project>
diff --git a/spring-boot-modules/spring-boot-mvc/pom.xml b/spring-boot-modules/spring-boot-mvc/pom.xml
index 6a951ace93..019d29285c 100644
--- a/spring-boot-modules/spring-boot-mvc/pom.xml
+++ b/spring-boot-modules/spring-boot-mvc/pom.xml
@@ -122,12 +122,12 @@
         <dependency>
             <groupId>org.aspectj</groupId>
             <artifactId>aspectjrt</artifactId>
-            <version>1.9.1</version>
+            <version>${aspectjweaver.version}</version>
         </dependency>
         <dependency>
             <groupId>org.aspectj</groupId>
             <artifactId>aspectjweaver</artifactId>
-            <version>1.9.1</version>
+            <version>${aspectjweaver.version}</version>
         </dependency>
 
     </dependencies>
diff --git a/spring-boot-modules/spring-boot-runtime/pom.xml b/spring-boot-modules/spring-boot-runtime/pom.xml
index df45537940..8c85735d8e 100644
--- a/spring-boot-modules/spring-boot-runtime/pom.xml
+++ b/spring-boot-modules/spring-boot-runtime/pom.xml
@@ -42,7 +42,7 @@
         <dependency>
             <groupId>commons-io</groupId>
             <artifactId>commons-io</artifactId>
-            <version>2.6</version>
+            <version>${commons-io.version}</version>
         </dependency>
 
         <dependency>
@@ -170,6 +170,7 @@
         <springcloud.version>2.0.2.RELEASE</springcloud.version>
         <httpclient.version>4.5.8</httpclient.version>
         <spring-boot-admin-starter-client.version>2.1.6</spring-boot-admin-starter-client.version>
+        <commons-io.version>2.6</commons-io.version>
     </properties>
 
 </project>
diff --git a/spring-boot-modules/spring-boot-security/pom.xml b/spring-boot-modules/spring-boot-security/pom.xml
index 98eceaff96..b9f28b68c4 100644
--- a/spring-boot-modules/spring-boot-security/pom.xml
+++ b/spring-boot-modules/spring-boot-security/pom.xml
@@ -22,17 +22,17 @@
         <dependency>
             <groupId>org.springframework.security.oauth</groupId>
             <artifactId>spring-security-oauth2</artifactId>
-            <version>2.4.0.RELEASE</version>
+            <version>${spring-security-oauth2.version}</version>
         </dependency>
         <dependency>
             <groupId>commons-io</groupId>
             <artifactId>commons-io</artifactId>
-            <version>2.6</version>
+            <version>${commons-io.version}</version>
         </dependency>
         <dependency>
             <groupId>org.springframework.security.oauth.boot</groupId>
             <artifactId>spring-security-oauth2-autoconfigure</artifactId>
-            <version>2.2.2.RELEASE</version>
+            <version>${spring-security-oauth2-autoconfigure.version}</version>
         </dependency>
         <dependency>
             <groupId>org.springframework.boot</groupId>
@@ -84,6 +84,10 @@
 
     <properties>
         <start-class>com.baeldung.springbootsecurity.basic_auth.SpringBootSecurityApplication</start-class>
+        <commons-io.version>2.6</commons-io.version>
+        <spring-security-oauth2.version>2.4.0.RELEASE</spring-security-oauth2.version>
+        <commons-io.version>2.6</commons-io.version>
+        <spring-security-oauth2-autoconfigure.version>2.2.2.RELEASE</spring-security-oauth2-autoconfigure.version>
     </properties>
 
 </project>
diff --git a/spring-cloud/spring-cloud-circuit-breaker/pom.xml b/spring-cloud/spring-cloud-circuit-breaker/pom.xml
index 188fc4bf8e..a179f3c831 100644
--- a/spring-cloud/spring-cloud-circuit-breaker/pom.xml
+++ b/spring-cloud/spring-cloud-circuit-breaker/pom.xml
@@ -44,7 +44,7 @@
         <dependency>
             <groupId>org.springframework.cloud</groupId>
             <artifactId>spring-cloud-starter-circuitbreaker-resilience4j</artifactId>
-            <version>1.0.2.RELEASE</version>
+            <version>${circuitbreaker-resilience4j.version}</version>
         </dependency>
         <dependency>
             <groupId>org.springframework.boot</groupId>
@@ -52,4 +52,8 @@
         </dependency>
     </dependencies>
 
+    <properties>
+        <circuitbreaker-resilience4j.version>1.0.2.RELEASE</circuitbreaker-resilience4j.version>
+    </properties>
+
 </project>
diff --git a/spring-cloud/spring-cloud-gateway/pom.xml b/spring-cloud/spring-cloud-gateway/pom.xml
index c692eed7ec..bbacf7a8ce 100644
--- a/spring-cloud/spring-cloud-gateway/pom.xml
+++ b/spring-cloud/spring-cloud-gateway/pom.xml
@@ -29,7 +29,7 @@
             <dependency>
                 <groupId>org.junit</groupId>
                 <artifactId>junit-bom</artifactId>
-                <version>5.5.2</version>
+                <version>${junit-bom.version}</version>
                 <type>pom</type>
                 <scope>import</scope>
             </dependency>
@@ -108,6 +108,7 @@
         <spring-boot.version>2.2.6.RELEASE</spring-boot.version>
         <hibernate-validator.version>6.0.2.Final</hibernate-validator.version>
         <redis.version>0.7.2</redis.version>
+        <junit-bom.version>5.5.2</junit-bom.version>
     </properties>
 
 </project>
diff --git a/spring-core-4/pom.xml b/spring-core-4/pom.xml
index fbec5ea9eb..299debbc3c 100644
--- a/spring-core-4/pom.xml
+++ b/spring-core-4/pom.xml
@@ -32,7 +32,7 @@
         <dependency>
             <groupId>com.google.guava</groupId>
             <artifactId>guava</artifactId>
-            <version>28.2-jre</version>
+            <version>${guava.version}</version>
         </dependency>
         <dependency>
             <groupId>org.springframework</groupId>
@@ -55,13 +55,13 @@
         <dependency>
             <groupId>org.awaitility</groupId>
             <artifactId>awaitility</artifactId>
-            <version>4.0.2</version>
+            <version>${awaitility.version}</version>
             <scope>test</scope>
         </dependency>
         <dependency>
             <groupId>org.assertj</groupId>
             <artifactId>assertj-core</artifactId>
-            <version>2.9.1</version>
+            <version>${assertj-core.version}</version>
             <scope>test</scope>
         </dependency>
     </dependencies>
@@ -80,6 +80,9 @@
         <maven.surefire.version>2.22.1</maven.surefire.version>
         <annotation-api.version>1.3.2</annotation-api.version>
         <spring.boot.version>2.2.2.RELEASE</spring.boot.version>
+        <guava.version>28.2-jre</guava.version>
+        <awaitility.version>4.0.2</awaitility.version>
+        <assertj-core.version>2.9.1</assertj-core.version>
     </properties>
 
 </project>
diff --git a/spring-dispatcher-servlet/pom.xml b/spring-dispatcher-servlet/pom.xml
index 9b9f7fb4c6..46e40722f1 100644
--- a/spring-dispatcher-servlet/pom.xml
+++ b/spring-dispatcher-servlet/pom.xml
@@ -63,7 +63,7 @@
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-test</artifactId>
-            <version>1.5.10.RELEASE</version>
+            <version>${spring-boot-starter-test.version}</version>
             <scope>test</scope>
         </dependency>
     </dependencies>
diff --git a/spring-mvc-forms-jsp/pom.xml b/spring-mvc-forms-jsp/pom.xml
index 2bab93908f..4e1c2516f6 100644
--- a/spring-mvc-forms-jsp/pom.xml
+++ b/spring-mvc-forms-jsp/pom.xml
@@ -64,7 +64,7 @@
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-test</artifactId>
-            <version>1.5.10.RELEASE</version>
+            <version>${spring-boot-starter-test.version}</version>
             <scope>test</scope>
         </dependency>
     </dependencies>
diff --git a/spring-mvc-webflow/pom.xml b/spring-mvc-webflow/pom.xml
index 22ae3c913d..ab0f86394a 100644
--- a/spring-mvc-webflow/pom.xml
+++ b/spring-mvc-webflow/pom.xml
@@ -57,7 +57,7 @@
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-test</artifactId>
-            <version>1.5.10.RELEASE</version>
+            <version>${spring-boot-starter-test.version}</version>
             <scope>test</scope>
         </dependency>
 
@@ -114,6 +114,7 @@
         <!-- Maven plugins -->
         <maven-resources-plugin.version>2.7</maven-resources-plugin.version>
         <cargo-maven2-plugin.version>1.6.1</cargo-maven2-plugin.version>
+        <spring-boot-starter-test.version>1.5.10.RELEASE</spring-boot-starter-test.version>
     </properties>
 
 </project>
\ No newline at end of file
diff --git a/spring-security-modules/spring-security-mvc-socket/pom.xml b/spring-security-modules/spring-security-mvc-socket/pom.xml
index ff8cc708e3..6515121f9f 100644
--- a/spring-security-modules/spring-security-mvc-socket/pom.xml
+++ b/spring-security-modules/spring-security-mvc-socket/pom.xml
@@ -152,7 +152,7 @@
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-test</artifactId>
-            <version>1.5.10.RELEASE</version>
+            <version>${spring-boot-starter-test.version}</version>
             <scope>test</scope>
         </dependency>
     </dependencies>
@@ -185,6 +185,7 @@
         <spring-security.version>4.2.3.RELEASE</spring-security.version>
         <spring-data-jpa.version>1.11.3.RELEASE</spring-data-jpa.version>
         <logback-classic.version>1.2.3</logback-classic.version>
+        <spring-boot-starter-test.version>1.5.10.RELEASE</spring-boot-starter-test.version>
     </properties>
 
 </project>
\ No newline at end of file