CU-86b2x4qmn_GH-133--how-to-remove-empty-xml-tags (#152)

Author: ptorres-prowide

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 #### 9.5.7 - SNAPSHOT
   * Enhanced the MX parser log verbosity when parsing malformed content
+  * Added new logic to MxNode to removing all leaves with empty attributes and empty content
 
 #### 9.5.6 - January 2025
   * Changed the `MxParseUtils` findByTags and findByPath methods to return the element values instead of the XML stream object

iso20022-core/src/main/java/com/prowidesoftware/swift/model/MxNode.java

@@ -299,4 +299,35 @@ public String path() {
             return this.parent.path() + PATH_SEPARATOR + this.localName;
         }
     }
+
+    /**
+     * Traverses the XML tree from this node down, removing all leaves with empty attributes and empty content.
+     *
+     * @since 9.5.7
+     */
+    public void removeEmptyElements() {
+        if (this.children != null && !this.children.isEmpty()) {
+            List<MxNode> removables = new ArrayList<>();
+            for (MxNode child : this.children) {
+                if (child.isEmpty()) {
+                    removables.add(child);
+                } else {
+                    child.removeEmptyElements();
+                }
+            }
+            for (MxNode removable : removables) {
+                this.children.remove(removable);
+            }
+        }
+    }
+
+    /**
+     * @return true if this node has no value, no attributes and no children
+     * @since 9.5.7
+     */
+    public boolean isEmpty() {
+        return StringUtils.isEmpty(this.value)
+                && (this.attributes == null || this.attributes.isEmpty())
+                && (this.children == null || this.children.isEmpty());
+    }
 }

iso20022-core/src/test/java/com/prowidesoftware/swift/model/MxNodeTest.java

@@ -413,4 +413,60 @@ public void testXxeDisabled() {
         final MxNode doc = MxNode.parse(xml);
         assertNull(doc);
     }
+
+    @Test
+    public void testRemoveEmptyElements() {
+        final MxNode n = new MxNode(null, "root");
+        new MxNode(n, "X").setValue("value"); // Add child with value
+        assertEquals(1, n.getChildren().size());
+
+        n.removeEmptyElements(); // Should not remove the child as it has value
+        assertFalse(n.getChildren().isEmpty()); // Still has children
+    }
+
+    @Test
+    public void testRemoveEmptyElements2() {
+        final MxNode n = new MxNode(null, "root");
+        MxNode x = new MxNode(n, "X");
+        x.addAttribute("a", "attr-value"); // Add an attribute
+        assertEquals(1, n.getChildren().size());
+
+        n.removeEmptyElements(); // Should not remove node as it has an attribute
+        assertFalse(n.getChildren().isEmpty());
+    }
+
+    @Test
+    public void testRemoveEmptyElements3() {
+        final MxNode n = new MxNode(null, "root");
+        new MxNode(n, "X"); // Create child node with no value and no attributes
+        assertEquals(1, n.getChildren().size());
+
+        n.removeEmptyElements(); // Should remove the child as it's empty
+        assertTrue(n.getChildren().isEmpty()); // No children left
+    }
+
+    @Test
+    public void testRemoveEmptyElements4() {
+        final MxNode n = new MxNode(null, "root");
+        MxNode x = new MxNode(n, "X");
+        new MxNode(x, "Y"); // Create an empty child under X
+
+        n.removeEmptyElements(); // Should remove Y as it's empty
+        assertEquals(1, n.getChildren().size()); // X should still exist
+        assertTrue(n.getChildren().get(0).getChildren().isEmpty()); // X should have no children
+    }
+
+    @Test
+    public void testRemoveEmptyElements5() {
+        final MxNode n = new MxNode(null, "root");
+        MxNode x = new MxNode(n, "X");
+        new MxNode(x, "Y").setValue("y"); // Add child with value
+        new MxNode(x, "Z").setValue(""); // Add child with empty value
+
+        assertEquals(1, n.getChildren().size());
+        assertEquals(2, x.getChildren().size());
+
+        n.removeEmptyElements(); // Should remove Z as it's empty
+        assertEquals(1, x.getChildren().size()); // Only Y should remain
+    }
 }