Reducing memory foot-print by 1) removing XPath property and creating…

… it on the fly 2) Number of recursions can be set by default three. The higher the more possible XPaths and XsdElements are being created

src/main/java/com/compare/xsd/comparison/XsdComparer.java

@@ -48,13 +48,24 @@ public XsdComparer(String oldDocument, String newDocument) {
      * @param reporterType determines the way the text output is provided
      */
     public XsdComparer(String oldDocument, String newDocument, TextReport.implementation reporterType) {
+        this(oldDocument,newDocument, reporterType, 3);
+    }
+    /**
+     * Initialize a new instance of {@link XsdComparer}.
+     *
+     * @param oldDocument Set the old document.
+     * @param newDocument      Set the new document.
+     * @param reporterType determines the way the text output is provided
+     * @param duplicatedAnchestorNoAllowed Set the recursion depth by limiting same anchestors
+     */
+    public XsdComparer(String oldDocument, String newDocument, TextReport.implementation reporterType, int duplicatedAnchestorNoAllowed) {
         Assert.notNull(oldDocument, "oldDocument cannot be null");
         Assert.notNull(newDocument, "newDocument cannot be null");
         this.textReport = getTextReporter(reporterType);
         XsdLoader xsdLoader = new XsdLoader(null);
-        this.oldDocument = xsdLoader.load(new File(oldDocument));
+        this.oldDocument = xsdLoader.load(new File(oldDocument), duplicatedAnchestorNoAllowed);
         log.debug("Finished loading original grammar!");
-        this.newDocument = xsdLoader.load(new File(newDocument));
+        this.newDocument = xsdLoader.load(new File(newDocument), duplicatedAnchestorNoAllowed);
         log.debug("Finished loading new grammar!");
     }
 
@@ -149,7 +160,7 @@ private void compareAbstractElementNodes(AbstractXsdElementNode oldNode, Abstrac
         increaseAncestor_OldGrammar(oldNode);
         increaseAncestor_NewGrammar(newNode);
         Assert.notNull(newNode, "newNode cannot be null");
-        assert(oldNode.xpath.equals(newNode.xpath));
+        assert(oldNode.getXPath().equals(newNode.getXPath()));
 
         List<XsdElement> oldElementChildren;
         List<XsdElement> newElementChildren;
@@ -172,7 +183,7 @@ private void compareAbstractElementNodes(AbstractXsdElementNode oldNode, Abstrac
                 XsdElement newChildElement = newNode.findElement(oldElementChild.getName(), "1: old child in new children: ");
                 compareXsdElementProperties(oldElementChild, newChildElement);
                 compareAbstractElementNodes(oldElementChild, newChildElement);
-                assert(!(oldElementChild == null || newChildElement == null || !oldElementChild.xpath.equals(newChildElement.xpath)));
+                assert(!(oldElementChild == null || newChildElement == null || !oldElementChild.getXPath().equals(newChildElement.getXPath())));
             } catch (NodeNotFoundException ex) {
                 assert(newNode.getXPath().equals(oldNode.getXPath()));
                 removed++;
@@ -230,7 +241,7 @@ private static Boolean alreadyCompared(AbstractXsdElementNode element, Map<Strin
         if(element instanceof XsdElement){
             String elementID = ((XsdElement) element).getUniqueId();
             Integer ancestorCount = ancestorMap.get(elementID);
-            if(ancestorCount != null && ancestorCount > 2){
+            if(ancestorCount != null && ancestorCount == element.getDocument().duplicatedAnchestorNoAllowed){
                 return Boolean.TRUE;
             }else{
                 return Boolean.FALSE;
@@ -272,7 +283,7 @@ private static void decreaseAncestor(AbstractXsdElementNode element, Map<String,
      * @param newNode      Set the new XSD element.
      */
     private void compareXsdElementProperties(XsdElement oldNode, XsdElement newNode) {
-        assert(oldNode.xpath.equals(newNode.xpath));
+        assert(oldNode.getXPath().equals(newNode.getXPath()));
 
         List<XsdAttribute> oldNodeAttributes = new ArrayList<>(oldNode.getAttributes()); //take a copy as the actual list might be modified during comparison
         List<XsdAttribute> newNodeAttributes = new ArrayList<>(newNode.getAttributes());
@@ -349,11 +360,11 @@ private void compareProperties(XsdNode oldNode, XsdNode newNode) {
                 modified++;
                 textReport.addChange(change);
                 if(newNode instanceof XsdElement){
-                    assert(( ((AbstractXsdNode) newNode).xpath != null && ((AbstractXsdNode) newNode).xpath != null && ((AbstractXsdNode) newNode).xpath.equals(((AbstractXsdNode) oldNode).xpath)));
+                    assert(( ((AbstractXsdNode) newNode).getXPath() != null && ((AbstractXsdNode) newNode).getXPath() != null && ((AbstractXsdNode) newNode).getXPath().equals(((AbstractXsdNode) oldNode).getXPath())));
                     assert(((XsdElement) newNode).getParent() != null);
 
                 }else if(newNode instanceof XsdAttribute) {
-                    assert ((((AbstractXsdNode) newNode).getParent().xpath != null && ((AbstractXsdNode) newNode).getParent().xpath != null && ((AbstractXsdNode) newNode).getParent().xpath.equals(((AbstractXsdNode) oldNode).getParent().xpath)));
+                    assert ((((AbstractXsdNode) newNode).getParent().getXPath() != null && ((AbstractXsdNode) newNode).getParent().getXPath() != null && ((AbstractXsdNode) newNode).getParent().getXPath().equals(((AbstractXsdNode) oldNode).getParent().getXPath())));
                 }
             }
         }

src/main/java/com/compare/xsd/comparison/XsdLoader.java

@@ -71,6 +71,17 @@ public XsdDocument chooseAndLoad() {
      * @return Returns the loaded {@link XsdDocument}.
      */
     public XsdDocument load(File file) {
+        return load(file, 3);
+    }
+
+    /**
+     * Load the given XSD file into a {@link XsdDocument}.
+     *
+     * @param file Set the XSD file to load.
+     * @param duplicatedAnchestorNoAllowed Set the recursion depth by limiting same anchestors     *
+     * @return Returns the loaded {@link XsdDocument}.
+     */
+    public XsdDocument load(File file, int duplicatedAnchestorNoAllowed) {
         Assert.notNull(file, "file cannot be null");
 
         // verify if the file exists
@@ -81,6 +92,7 @@ public XsdDocument load(File file) {
         }
 
         log.debug("Loading xsd file " + file);
-        return new XsdDocument(file);
+        return new XsdDocument(file, duplicatedAnchestorNoAllowed);
     }
+
 }

src/main/java/com/compare/xsd/comparison/model/xsd/impl/AbstractXsdNode.java

@@ -42,7 +42,7 @@ public abstract class AbstractXsdNode implements XsdNode {
                     break;
 
  */
-    public String xpath;
+    protected StringBuilder sb = new StringBuilder();
     protected String name;
     protected String typeNamespace;
     protected String typeName;
@@ -139,7 +139,20 @@ public Image getModificationColor() {
 
     @Override
     public String getXPath() {
-        return xpath;
+        if(this instanceof XsdDocument){
+            return "/";
+        }else{
+            StringBuilder sb = getXPath(this.parent).append("/").append(this.name);
+            return sb.toString();
+        }
+    }
+
+    public StringBuilder getXPath(AbstractXsdNode node) {
+        if(node instanceof XsdDocument){
+            return ((XsdDocument) node).getStringBuilder();
+        }else {
+            return getXPath(node.parent).append("/").append(node.name);
+        }
     }
 
     //endregion

src/main/java/com/compare/xsd/comparison/model/xsd/impl/XsdAttribute.java

@@ -105,7 +105,7 @@ public List<XsdNode> getNodes() {
 
     @Override
     public String getXPath() {
-        return parent.xpath + "/@" + getName();
+        return parent.getXPath() + "/@" + getName();
     }
 
     @Override

src/main/java/com/compare/xsd/comparison/model/xsd/impl/XsdDocument.java

@@ -5,26 +5,14 @@
 import javafx.scene.image.Image;
 import lombok.Data;
 import lombok.EqualsAndHashCode;
-import org.apache.xerces.dom.DOMXSImplementationSourceImpl;
 import org.apache.xerces.impl.xs.XSElementDecl;
 import org.apache.xerces.impl.xs.XSLoaderImpl;
 import org.apache.xerces.impl.xs.XSModelImpl;
 import org.apache.xerces.xs.*;
 import org.springframework.util.Assert;
-import org.w3c.dom.DOMImplementation;
-import org.w3c.dom.Document;
-import org.w3c.dom.bootstrap.DOMImplementationRegistry;
-import org.xml.sax.SAXException;
 
 import javax.xml.parsers.DocumentBuilder;
-import javax.xml.parsers.DocumentBuilderFactory;
-import javax.xml.parsers.ParserConfigurationException;
 import java.io.File;
-import java.io.IOException;
-import java.net.URI;
-import java.net.URISyntaxException;
-import java.nio.file.Path;
-import java.nio.file.Paths;
 import java.util.*;
 
 @EqualsAndHashCode(callSuper = true)
@@ -34,7 +22,9 @@ public class XsdDocument extends AbstractXsdElementNode {
     public Stack<String> xPathStack = new Stack<>();
     public Map<String, Integer> ancestorCountByelementIO = new HashMap();
     private DocumentBuilder builder;
-
+    public int duplicatedAnchestorNoAllowed = 2;
+    private StringBuilder sb;
+    private static final String XPATH_ROOT = "/";
     //region Constructors
 
     /**
@@ -45,7 +35,24 @@ public class XsdDocument extends AbstractXsdElementNode {
     public XsdDocument(File file) {
         Assert.notNull(file, "file cannot be null");
         this.file = file;
+        init();
+    }
 
+    public StringBuilder getStringBuilder() {
+        sb.delete(0, sb.length());
+        return sb;
+    }
+
+    /**
+     * Initialize a new instance of {@link XsdDocument}.
+     *
+     * @param file Set the XSD file to load.
+     * @param duplicatedAnchestorNoAllowed Set the recursion depth by limiting same anchestors
+     */
+    public XsdDocument(File file, int duplicatedAnchestorNoAllowed) {
+        Assert.notNull(file, "file cannot be null");
+        this.file = file;
+        this.duplicatedAnchestorNoAllowed = duplicatedAnchestorNoAllowed;
         init();
     }
 
@@ -77,7 +84,7 @@ public Image getModificationColor() {
 
     @Override
     public String getXPath() {
-        return xpath;
+        return XPATH_ROOT;
     }
 
 
@@ -101,12 +108,11 @@ private void init() {
         var loader = new XSLoaderImpl();
         // XSD is now parsed by Xerces the XSModelImpl holds all information
         XSModelImpl model = (XSModelImpl) loader.loadURI(file.getAbsolutePath());
-
         // start to bootstrap our model by accessing the map of all root elements
         XSNamedMap elements = model.getComponents(XSConstants.ELEMENT_DECLARATION);
 
+        this.sb = new StringBuilder();
         this.name = file.getName();
-        this.xpath = "//";
 
         // check every root element
         for (Object item : elements.values()) {

src/main/java/com/compare/xsd/comparison/model/xsd/impl/XsdElement.java

@@ -53,7 +53,7 @@ private XsdElement(XSElementDeclaration elementDecl, XsdDocument document) {
         this.name = elementDecl.getName();
         this.typeNamespace = loadNamespace(this);
         document.xPathStack.push(name);
-        this.xpath = createXPath(this.document.xPathStack);
+//        this.xpath = createXPath(this.document.xPathStack);
     }
 
     /**
@@ -92,7 +92,8 @@ private XsdElement(XSParticle particle, XsdElement parent, short compositor) {
         this.typeNamespace = loadNamespace(this);
         this.document = parent.getDocument();
         this.document.xPathStack.push(name);
-        this.xpath = createXPath(this.document.xPathStack);
+        //log.debug("Creating new element " + this.name + " at " + xpath);
+        //System.err.println("Creating new element: " + getXPath());
     }
 
     /**
@@ -150,21 +151,13 @@ public static XsdElement newXsdElement(XSParticle particle, XsdElement parent, s
         }
     }
 
-    private static String createXPath(Stack<String> ancestorNames){
-        StringBuilder xPath = new StringBuilder();
-        for(String name : ancestorNames){
-            xPath.append("/").append(name);
-        }
-        return xPath.toString();
-    }
-
     public String getUniqueId(){
         return XsdElement.getUniqueId(elementDecl, minOccurrence, maxOccurrence);
     }
 
     static private Boolean hasTooManySameAncestors(XsdDocument document, String elementID){
         Integer count = document.ancestorCountByelementIO.get(elementID);
-        if(count != null && count > 3){
+        if(count != null && count == document.duplicatedAnchestorNoAllowed){
             return Boolean.TRUE;
         }else{
             return Boolean.FALSE;

src/test/java/com/compare/xsd/comparison/XsdComparerTest.java

@@ -18,6 +18,7 @@
 import java.nio.file.Files;
 import java.nio.file.Paths;
 import java.nio.file.StandardOpenOption;
+import java.util.*;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertTrue;
@@ -114,12 +115,76 @@ public void multiComparisonTest() throws IOException {
         assertTrue(compareCorrect,"\nRegression test fails as reference was different!\nNote: If the test fails due to a new output (e.g. programming update) copy the new result over the old reference:\n\t" + TARGET_DIR + "\n\t\tto" + "\n\t" + REFERENCES_DIR);
     }
 
+/************************************************************************************************/
+/* NOTE: Following compare of UBL 2.1 with UBL 2.3 will throw an out-of-memory exception!    ****/
+/************************************************************************************************/
+/*
+    private static final String UBL_2_1_XSD_PATH = XSD_DIR +  "UBL-2.1" + File.separator + "xsd" + File.separator + "maindoc" + File.separator;
+    private static final String UBL_2_3_XSD_PATH = XSD_DIR +  "UBL-2.3" + File.separator + "xsd" + File.separator + "maindoc" + File.separator;
+    private static final String EMPTY_XSD_FILE_PATH = XSD_DIR + "empty.xsd";
+    @Test
+    /** Compares several XSDs pairs and compares the result with the saved reference. */
+    /*
+    public void UBLComparisonTest() throws IOException {
+
+        Boolean compareCorrect = Boolean.TRUE;
+
+        // Creates a new File instance by converting the given pathname string
+        // into an abstract pathname
+        File directoryUBL21 = new File(UBL_2_1_XSD_PATH);
+        File directoryUBL23 = new File(UBL_2_3_XSD_PATH);
+
+        // Populates the array with names of files and directories
+        String[] fileNames_Ubl2_1 = directoryUBL21.list();
+        Set<String> fileNames_Ubl2_1Set = Set.of(fileNames_Ubl2_1);
+        String[] fileNames_Ubl2_3 = directoryUBL23.list();
+        Set<String> fileNames_Ubl2_3Set = new TreeSet<>(Set.of(fileNames_Ubl2_3));
+
+        String xsdFilePath_ubl2_1;
+
+        // For each pathname in the fileNames array
+        for (String xsdFileName_ubl2_3 : fileNames_Ubl2_3Set) {
+            // Print the names of files and directories
+            xsdFilePath_ubl2_1 = xsdFilePath_ubl2_1(xsdFileName_ubl2_3, fileNames_Ubl2_1Set);
+            if(xsdFilePath_ubl2_1 != null){
+                System.out.println("\nComparing:\n" + xsdFilePath_ubl2_1.substring(xsdFilePath_ubl2_1.lastIndexOf(File.separator) + 1, xsdFilePath_ubl2_1.length()) + "\nwith\n" + xsdFileName_ubl2_3);
+                for(TextReport.implementation reportType : TextReport.implementation.values()){
+                    compareCorrect &= compareTwoXsdGrammars(xsdFilePath_ubl2_1, UBL_2_3_XSD_PATH + xsdFileName_ubl2_3, reportType, 1);
+                }
+            }
+        }
+        assertTrue(compareCorrect,"\nRegression test fails as reference was different!\nNote: If the test fails due to a new output (e.g. programming update) copy the new result over the old reference:\n\t" + TARGET_DIR + "\n\t\tto" + "\n\t" + REFERENCES_DIR);
+    }
+
+    /** Returning the correspondent UBL 2.1 file path according to the UBL 2.3 file name (or if not existent the file to an empty XSD file
+     * for instance the input file name "UBL-CatalogueRequest-2.3.xsd" will look for "UBL-CatalogueRequest-2.1.xsd" in the UBL 2.1 directory.
+     * */
+/*
+    private static String xsdFilePath_ubl2_1(String xsdFileName_ubl2_3, Set fileNameSet_Ubl2_1){
+        String xsdFilePath_ubl2_1 = null;
+        int i = xsdFileName_ubl2_3.lastIndexOf("-2.3.xsd");
+        String xsdFileName_ubl2_1 = xsdFileName_ubl2_3.substring(0, xsdFileName_ubl2_3.lastIndexOf("-2.3.xsd")) + "-2.1.xsd";
+        if(fileNameSet_Ubl2_1.contains(xsdFileName_ubl2_1)){
+            xsdFilePath_ubl2_1 = UBL_2_1_XSD_PATH + xsdFileName_ubl2_1;
+        }else{
+            System.out.println("New XSD file in UBL 2.3: " + xsdFileName_ubl2_3);
+            //xsdFilePath_ubl2_1 = EMPTY_XSD_FILE_PATH;
+        }
+        return xsdFilePath_ubl2_1;
+    }
+
+*/
+
 
     /** Comparing two XSD grammar with a specific text report for the output*/
     private boolean compareTwoXsdGrammars(String newXsd, String oldXsd, TextReport.implementation reportType) throws IOException {
+        return compareTwoXsdGrammars(newXsd, oldXsd, reportType, 3);
+    }
+
+    private boolean compareTwoXsdGrammars(String newXsd, String oldXsd, TextReport.implementation reportType, int duplicatedAnchestorNoAllowed) throws IOException {
         Boolean compareCorrect = Boolean.TRUE;
         String reportName = getReportName(newXsd, oldXsd, reportType);
-        XsdComparer comparer = new XsdComparer(newXsd, oldXsd, reportType);
+        XsdComparer comparer = new XsdComparer(newXsd, oldXsd, reportType, duplicatedAnchestorNoAllowed);
         String result = comparer.compareAsString();
         System.out.println(result);
         // if you change the programming, update the reference by copying new result as new reference!

src/test/java/com/compare/xsd/comparison/model/xsd/impl/XsdDocumentTest.java

@@ -68,7 +68,7 @@ public void testFileConstructor_shouldRootElementContainExpectedChildElementsWhe
     @Test
     public void shouldReturnTheExpectedResultWhenGetXPathIsCalled() {
         //GIVEN
-        final String expectedResult = "//";
+        final String expectedResult = "/";
 
         //WHEN
         XsdDocument result = new XsdDocument(file);

src/test/resources/xsd/empty.xsd

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"
+            targetNamespace="empty"
+            elementFormDefault="qualified"
+            attributeFormDefault="unqualified">
+</xsd:schema>