Adding recursive child xml node deletion to support GS*Encoder-centric implementation of #199.

src/main/java/it/geosolutions/geoserver/rest/GeoServerRESTPublisher.java

@@ -3273,14 +3273,8 @@ public class GeoServerRESTPublisher {
 
         String sUrl = baseUrl + "?recalculate=" + calculationMode.getParamValue();
         LOGGER.debug("Constructed the following url for bounding box recalculation: " + sUrl);
-        
 
-//        String body = wsenc.toString();
+        renc.recursivelyRemoveEmptyChildren();
-//        String body = "<" + xmlElementName +"><name>" + layerName + "</name>" + 
-//                "<enabled>" + enabled + "</enabled></" + xmlElementName + ">";
-        renc.remove(GSResourceEncoder.KEYWORDS);
-        renc.remove(GSResourceEncoder.METADATA);
-        renc.remove(GSResourceEncoder.METADATALINKS);
         String body = renc.toString();
         String sendResult = HTTPUtils.putXml(sUrl, body, gsuser, gspass);
         boolean success = sendResult != null;

src/main/java/it/geosolutions/geoserver/rest/encoder/utils/XmlElement.java

@@ -26,9 +26,13 @@
 package it.geosolutions.geoserver.rest.encoder.utils;
 
 
+import java.util.ArrayList;
+import java.util.List;
 import org.jdom.Content;
 import org.jdom.Element;
 import org.jdom.Text;
+import org.jdom.filter.ContentFilter;
+import org.jdom.filter.ElementFilter;
 import org.jdom.output.Format;
 import org.jdom.output.XMLOutputter;
 
@@ -122,6 +126,35 @@ public class XmlElement{
 			return false;
 	}
 	
+    public void recursivelyRemoveEmptyChildren(){
+        //must make a copy to avoid ConcurrentModificationException
+        List<Content> children = new ArrayList<Content>(this.root.getContent());
+  
+        for(Content child : children){
+            if(child instanceof Element){
+                recursivelyRemoveEmptyChildren(this.root, (Element)child);
+            }
+        }
+    }
+    private void recursivelyRemoveEmptyChildren(Element grandparent, Element parent){
+        //must make a copy to avoid ConcurrentModificationException
+        List<Content> childrenPreRemoval;
+        childrenPreRemoval = new ArrayList<Content>(parent.getContent());
+        
+        //base case: the parent has no children
+        for(Content child : childrenPreRemoval){
+            //recursive case: the parent has children
+            if(child instanceof Element){
+                recursivelyRemoveEmptyChildren(parent, (Element)child);
+            }
+        }
+        
+        //if the parent node contains no children, remove it from the parent
+        List<Content> childrenPostRemoval = parent.getContent();
+        if(childrenPostRemoval.isEmpty()){
+            grandparent.removeContent(parent);
+        }
+    }
 	/**
      * @return an xml String 
      */

src/test/java/it/geosolutions/geoserver/rest/encoder/utils/XmlElementTest.java

@@ -0,0 +1,119 @@
+package it.geosolutions.geoserver.rest.encoder.utils;
+
+import java.io.IOException;
+import java.io.StringReader;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+import org.jdom.Document;
+import org.jdom.Element;
+import org.jdom.JDOMException;
+import org.jdom.input.SAXBuilder;
+import org.jdom.output.XMLOutputter;
+import org.junit.After;
+import org.junit.AfterClass;
+import org.junit.Before;
+import org.junit.BeforeClass;
+import org.junit.Test;
+import static org.junit.Assert.*;
+
+public class XmlElementTest {
+
+    public XmlElementTest() {
+    }
+
+    @BeforeClass
+    public static void setUpClass() {
+    }
+
+    @AfterClass
+    public static void tearDownClass() {
+    }
+
+    @Before
+    public void setUp() {
+    }
+
+    @After
+    public void tearDown() {
+    }
+
+    private XmlElement makeElement(String docString){
+        Document doc;
+        SAXBuilder builder = new SAXBuilder();
+        try {
+            doc = builder.build(new StringReader(docString));
+        } catch (JDOMException ex) {
+            throw new RuntimeException(ex);
+        } catch (IOException ex) {
+            throw new RuntimeException(ex);
+        }
+        Element root = doc.getRootElement();
+        
+        return new XmlElement(root);
+    }
+    
+    private void assertEqualXml(String message, XmlElement expected, XmlElement actual){
+        XMLOutputter out = new XMLOutputter();
+        String expectedElementString = out.outputString(expected.getRoot());
+        String actualElementString = out.outputString(actual.getRoot());
+        assertEquals(message, expectedElementString, actualElementString);
+    }
+    
+    @Test
+    public void testRecursiveRemovalOnChildlessParent(){
+        XmlElement root = makeElement("<parent/>");
+        root.recursivelyRemoveEmptyChildren();
+        assertEqualXml("no child elements expected", makeElement("<parent/>"), root);
+    }
+    
+    @Test
+    public void testRecursiveRemovalOfOneChild(){
+        XmlElement root = makeElement("<parent><child/></parent>");
+        root.recursivelyRemoveEmptyChildren();
+        assertEqualXml("no child elements expected", makeElement("<parent/>"), root);
+    }
+    
+    @Test
+    public void testRecursiveRemovalOfOneChildWithOneKeeper(){
+        XmlElement root = makeElement("<parent><child/><keep>keep</keep></parent>");
+        root.recursivelyRemoveEmptyChildren();
+        assertEqualXml("one child element expected", makeElement("<parent><keep>keep</keep></parent>"), root);
+    }
+    
+    @Test
+    public void testRecursiveRemovalOfOneParentAndOneChild() {
+        XmlElement root = makeElement("<grandparent><parent><child/></parent></grandparent>");
+        root.recursivelyRemoveEmptyChildren();
+        assertEqualXml("no child elements expected", makeElement("<grandparent/>"), root);
+    }
+    
+    @Test
+    public void testRecursiveRemovalOfOneParentAndManyChildren() {
+        XmlElement root = makeElement("<grandparent><parent><child/><child/><child/></parent></grandparent>");
+        root.recursivelyRemoveEmptyChildren();
+        assertEqualXml("no child elements expected", makeElement("<grandparent/>"), root);
+    }
+    
+    @Test
+    public void testRecursiveRemovalOfManyParentsWithOneChild() {
+        XmlElement root = makeElement("<grandparent><parent><child/></parent><parent><child/></parent><parent><child/></parent></grandparent>");
+        root.recursivelyRemoveEmptyChildren();
+        assertEqualXml("no child elements expected", makeElement("<grandparent/>"), root);
+    }
+
+    @Test
+    public void testRecursiveRemovalOfManyParentsAndManyChildren() {
+        XmlElement root = makeElement("<grandparent><parent><child/><child/><child/></parent><parent><child/><child/><child/></parent><parent><child/><child/><child/></parent></grandparent>");
+        root.recursivelyRemoveEmptyChildren();
+        assertEqualXml("no child elements expected", makeElement("<grandparent/>"), root);
+    }
+
+    @Test
+    public void testRecursiveRemovalOfManyParentsAndManyChildrenWithSomeKeepers() {
+        XmlElement root = makeElement("<grandparent><keep>keep</keep><parent><keep>keep</keep><child/><child><keep>keep</keep></child><child/></parent><parent><child/><child/><child/></parent><parent><child/><child/><child><keep>keep</keep></child></parent></grandparent>");
+        root.recursivelyRemoveEmptyChildren();
+        assertEqualXml("only non-empty child elements should remain", makeElement("<grandparent><keep>keep</keep><parent><keep>keep</keep><child><keep>keep</keep></child></parent><parent><child><keep>keep</keep></child></parent></grandparent>"), root);
+    }
+    
+
+}