diff --git a/spring-core-2/src/main/java/com/baeldung/interpolation/NotNullRequest.java b/spring-core-2/src/main/java/com/baeldung/interpolation/NotNullRequest.java
new file mode 100644
index 0000000000..9a2b00be8f
--- /dev/null
+++ b/spring-core-2/src/main/java/com/baeldung/interpolation/NotNullRequest.java
@@ -0,0 +1,17 @@
+package com.baeldung.interpolation;
+
+import javax.validation.constraints.NotNull;
+
+public class NotNullRequest {
+
+    @NotNull(message = "stringValue has to be present")
+    private String stringValue;
+
+    public String getStringValue() {
+        return stringValue;
+    }
+
+    public void setStringValue(String stringValue) {
+        this.stringValue = stringValue;
+    }
+}
diff --git a/spring-core-2/src/main/java/com/baeldung/interpolation/RestController.java b/spring-core-2/src/main/java/com/baeldung/interpolation/RestController.java
new file mode 100644
index 0000000000..87b16320fe
--- /dev/null
+++ b/spring-core-2/src/main/java/com/baeldung/interpolation/RestController.java
@@ -0,0 +1,15 @@
+package com.baeldung.interpolation;
+
+import javax.validation.Valid;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+public class RestController {
+
+    @PostMapping("/test-not-null")
+    public void testNotNull(@Valid @RequestBody NotNullRequest request) {
+
+    }
+}
diff --git a/spring-core-2/src/main/java/com/baeldung/interpolation/ValidationExamples.java b/spring-core-2/src/main/java/com/baeldung/interpolation/ValidationExamples.java
new file mode 100644
index 0000000000..d353e4f7f2
--- /dev/null
+++ b/spring-core-2/src/main/java/com/baeldung/interpolation/ValidationExamples.java
@@ -0,0 +1,31 @@
+package com.baeldung.interpolation;
+
+import java.util.Formatter;
+import javax.validation.constraints.Size;
+import javax.validation.constraints.Min;
+import javax.validation.constraints.DecimalMin;
+
+public class ValidationExamples {
+
+    private static final Formatter formatter = new Formatter();
+
+    @Size(
+            min = 5,
+            max = 14,
+            message = "The author email '${validatedValue}' must be between {min} and {max} characters long"
+    )
+    private String authorEmail;
+
+    @Min(
+            value = 1,
+            message = "There must be at least {value} test{value > 1 ? 's' : ''} int the test case"
+    )
+    private int testCount;
+
+    @DecimalMin(
+            value = "50",
+            message = "The code coverage ${formatter.format('%1$.2f', validatedValue)} must be higher than {value}%"
+    )
+    private double codeCoverage;
+
+}