Added support common annotation

spring-data-mongodb/src/main/java/org/baeldung/model/User.java

@@ -1,7 +1,14 @@
 package org.baeldung.model;
 
+import java.util.Calendar;
+
 import org.baeldung.annotation.CascadeSave;
+import org.springframework.beans.factory.annotation.Value;
 import org.springframework.data.annotation.Id;
+import org.springframework.data.annotation.PersistenceConstructor;
+import org.springframework.data.annotation.Transient;
+import org.springframework.data.mongodb.core.index.CompoundIndex;
+import org.springframework.data.mongodb.core.index.CompoundIndexes;
 import org.springframework.data.mongodb.core.index.IndexDirection;
 import org.springframework.data.mongodb.core.index.Indexed;
 import org.springframework.data.mongodb.core.mapping.DBRef;
@@ -12,13 +19,14 @@ import com.mysema.query.annotations.QueryEntity;
 
 @QueryEntity
 @Document
+@CompoundIndexes({ @CompoundIndex(name = "email_age", def = "{'email.id' : 1, 'age': 1}") })
 public class User {
 
     @Id
     private String id;
     @Indexed(direction = IndexDirection.ASCENDING)
     private String name;
-
+    @Indexed(direction = IndexDirection.ASCENDING)
     private Integer age;
 
     @DBRef
@@ -26,6 +34,19 @@ public class User {
     @CascadeSave
     private EmailAddress emailAddress;
 
+    @Transient
+    private Integer yearOfBirth;
+
+    public User() {
+    }
+
+    @PersistenceConstructor
+    public User(final String name, @Value("#root.age ?: 0") final Integer age, final EmailAddress emailAddress) {
+        this.name = name;
+        this.age = age;
+        this.emailAddress = emailAddress;
+    }
+
     public String getId() {
         return id;
     }
@@ -57,4 +78,8 @@ public class User {
     public void setEmailAddress(EmailAddress emailAddress) {
         this.emailAddress = emailAddress;
     }
+
+    public Integer getYearOfBirth() {
+        return Calendar.getInstance().get(Calendar.YEAR) - age;
+    }
 }