BAEL-4643: JPA CascadeType.REMOVE vs orphanRemoval

* Defines the Domain: ShipmentInfo, LineItem and OrderRequest entity
* Adds CascadeTypeRemoveIntegrationTest
* Adds OrphanRemovalIntegrationTest

persistence-modules/java-jpa-3/src/main/java/com/baeldung/jpa/removal/LineItem.java

@@ -0,0 +1,42 @@
+package com.baeldung.jpa.removal;
+
+import java.util.Objects;
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.GenerationType;
+import javax.persistence.Id;
+import javax.persistence.ManyToOne;
+
+@Entity
+public class LineItem {
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.AUTO)
+    private Long id;
+
+    private String name;
+
+    @ManyToOne
+    private OrderRequest orderRequest;
+
+    public LineItem(String name) {
+        this.name = name;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+
+        LineItem lineItem = (LineItem) o;
+
+        return Objects.equals(id, lineItem.id);
+    }
+
+    @Override
+    public int hashCode() {
+        return id != null ? id.hashCode() : 0;
+    }
+
+    protected LineItem() {}
+}

persistence-modules/java-jpa-3/src/main/java/com/baeldung/jpa/removal/OrderRequest.java

@@ -0,0 +1,38 @@
+package com.baeldung.jpa.removal;
+
+import java.util.List;
+import javax.persistence.CascadeType;
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.GenerationType;
+import javax.persistence.Id;
+import javax.persistence.OneToMany;
+import javax.persistence.OneToOne;
+
+@Entity
+public class OrderRequest {
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.AUTO)
+    private Long id;
+
+    @OneToOne(cascade = { CascadeType.REMOVE, CascadeType.PERSIST })
+    private ShipmentInfo shipmentInfo;
+
+    @OneToMany(orphanRemoval = true, cascade = CascadeType.PERSIST, mappedBy = "orderRequest")
+    private List<LineItem> lineItems;
+
+    public OrderRequest(ShipmentInfo shipmentInfo) {
+        this.shipmentInfo = shipmentInfo;
+    }
+
+    public OrderRequest(List<LineItem> lineItems) {
+        this.lineItems = lineItems;
+    }
+
+    public void removeLineItem(LineItem lineItem) {
+        lineItems.remove(lineItem);
+    }
+
+    protected OrderRequest() {}
+}

persistence-modules/java-jpa-3/src/main/java/com/baeldung/jpa/removal/ShipmentInfo.java

@@ -0,0 +1,22 @@
+package com.baeldung.jpa.removal;
+
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.GenerationType;
+import javax.persistence.Id;
+
+@Entity
+public class ShipmentInfo {
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.AUTO)
+    private Long id;
+
+    private String name;
+
+    public ShipmentInfo(String name) {
+        this.name = name;
+    }
+
+    protected ShipmentInfo() {}
+}