CAY-2874 Define project XML version in one place

* Add ProjectVersion value-based class.
* Extract building of XML namespaces and schema locations to a utility class.

Author: m-dzianishchyts

cayenne-cgen/src/main/java/org/apache/cayenne/gen/xml/CgenExtension.java

@@ -20,8 +20,9 @@
 
 import org.apache.cayenne.configuration.ConfigurationNodeVisitor;
 import org.apache.cayenne.configuration.xml.DataChannelMetaData;
+import org.apache.cayenne.configuration.xml.ProjectVersion;
+import org.apache.cayenne.configuration.xml.Schema;
 import org.apache.cayenne.di.Inject;
-import org.apache.cayenne.project.Project;
 import org.apache.cayenne.project.extension.BaseNamingDelegate;
 import org.apache.cayenne.project.extension.LoaderDelegate;
 import org.apache.cayenne.project.extension.ProjectExtension;
@@ -32,7 +33,7 @@
  */
 public class CgenExtension implements ProjectExtension {
 
-    public static final String NAMESPACE = "http://cayenne.apache.org/schema/" + Project.VERSION + "/cgen";
+    public static final String NAMESPACE = Schema.buildNamespace(ProjectVersion.getCurrent(), "cgen");
 
     @Inject
     private DataChannelMetaData metaData;

cayenne-dbsync/src/main/java/org/apache/cayenne/dbsync/xml/DbImportExtension.java

@@ -21,8 +21,9 @@
 
 import org.apache.cayenne.configuration.ConfigurationNodeVisitor;
 import org.apache.cayenne.configuration.xml.DataChannelMetaData;
+import org.apache.cayenne.configuration.xml.ProjectVersion;
+import org.apache.cayenne.configuration.xml.Schema;
 import org.apache.cayenne.di.Inject;
-import org.apache.cayenne.project.Project;
 import org.apache.cayenne.project.extension.BaseNamingDelegate;
 import org.apache.cayenne.project.extension.LoaderDelegate;
 import org.apache.cayenne.project.extension.ProjectExtension;
@@ -33,7 +34,7 @@
  */
 public class DbImportExtension implements ProjectExtension {
 
-    public static final String NAMESPACE = "http://cayenne.apache.org/schema/" + Project.VERSION + "/dbimport";
+    public static final String NAMESPACE = Schema.buildNamespace(ProjectVersion.getCurrent(), "dbimport");
 
     @Inject
     private DataChannelMetaData metaData;

cayenne-project/src/main/java/org/apache/cayenne/project/ConfigurationSaver.java

@@ -22,6 +22,7 @@
 
 import org.apache.cayenne.configuration.BaseConfigurationNodeVisitor;
 import org.apache.cayenne.configuration.DataChannelDescriptor;
+import org.apache.cayenne.configuration.xml.ProjectVersion;
 import org.apache.cayenne.map.DataMap;
 import org.apache.cayenne.project.extension.SaverDelegate;
 import org.apache.cayenne.util.XMLEncoder;
@@ -33,10 +34,10 @@
 class ConfigurationSaver extends BaseConfigurationNodeVisitor<Void> {
 
     private PrintWriter printWriter;
-    private String version;
+    private ProjectVersion version;
     private SaverDelegate delegate;
 
-    ConfigurationSaver(PrintWriter printWriter, String version, SaverDelegate delegate) {
+    ConfigurationSaver(PrintWriter printWriter, ProjectVersion version, SaverDelegate delegate) {
         this.printWriter = printWriter;
         this.version = version;
         this.delegate = delegate;

cayenne-project/src/main/java/org/apache/cayenne/project/FileProjectSaver.java

@@ -22,6 +22,7 @@
 import org.apache.cayenne.configuration.ConfigurationNameMapper;
 import org.apache.cayenne.configuration.ConfigurationNode;
 import org.apache.cayenne.configuration.ConfigurationNodeVisitor;
+import org.apache.cayenne.configuration.xml.ProjectVersion;
 import org.apache.cayenne.di.Inject;
 import org.apache.cayenne.map.DataMap;
 import org.apache.cayenne.project.extension.ProjectExtension;
@@ -77,8 +78,8 @@ public FileProjectSaver(@Inject List<ProjectExtension> extensions) {
     }
 
     @Override
-    public String getSupportedVersion() {
-        return String.valueOf(Project.VERSION);
+    public ProjectVersion getSupportedVersion() {
+        return ProjectVersion.getCurrent();
     }
 
     @Override

cayenne-project/src/main/java/org/apache/cayenne/project/Project.java

@@ -25,6 +25,7 @@
 import org.apache.cayenne.configuration.ConfigurationNode;
 import org.apache.cayenne.configuration.ConfigurationNodeVisitor;
 import org.apache.cayenne.configuration.ConfigurationTree;
+import org.apache.cayenne.configuration.xml.ProjectVersion;
 import org.apache.cayenne.resource.Resource;
 
 /**
@@ -41,8 +42,10 @@ public class Project {
 	 * Used by different parsers and savers of project's XML files.
 	 *
 	 * @since 4.1
+	 * @deprecated since 5.0 use {@link ProjectVersion#getCurrent()} instead
 	 */
-	static public final int VERSION = 11;
+	@Deprecated(since = "5.0", forRemoval = true)
+	public static final int VERSION = (int) ProjectVersion.getCurrent().getAsDouble();
 
 	protected boolean modified;
 

cayenne-project/src/main/java/org/apache/cayenne/project/ProjectSaver.java

@@ -18,6 +18,7 @@
  ****************************************************************/
 package org.apache.cayenne.project;
 
+import org.apache.cayenne.configuration.xml.ProjectVersion;
 import org.apache.cayenne.resource.Resource;
 
 /**
@@ -30,7 +31,7 @@ public interface ProjectSaver {
     /**
      * Returns a version of the project configuration supported by the current runtime.
      */
-    String getSupportedVersion();
+    ProjectVersion getSupportedVersion();
 
     /**
      * Saves project in the location of its current configuration sources. Since resource

cayenne-project/src/main/java/org/apache/cayenne/project/extension/info/InfoExtension.java

@@ -21,8 +21,9 @@
 
 import org.apache.cayenne.configuration.ConfigurationNodeVisitor;
 import org.apache.cayenne.configuration.xml.DataChannelMetaData;
+import org.apache.cayenne.configuration.xml.ProjectVersion;
+import org.apache.cayenne.configuration.xml.Schema;
 import org.apache.cayenne.di.Inject;
-import org.apache.cayenne.project.Project;
 import org.apache.cayenne.project.extension.BaseNamingDelegate;
 import org.apache.cayenne.project.extension.LoaderDelegate;
 import org.apache.cayenne.project.extension.ProjectExtension;
@@ -37,7 +38,7 @@
  */
 public class InfoExtension implements ProjectExtension {
 
-    static final String NAMESPACE = "http://cayenne.apache.org/schema/" + Project.VERSION + "/info";
+    static final String NAMESPACE = Schema.buildNamespace(ProjectVersion.getCurrent(), "info");
 
     @Inject
     private DataChannelMetaData metaData;

cayenne-project/src/main/java/org/apache/cayenne/project/upgrade/DefaultUpgradeService.java

@@ -23,7 +23,6 @@
 import java.net.URL;
 import java.util.ArrayList;
 import java.util.Collection;
-import java.util.Comparator;
 import java.util.List;
 import java.util.Map;
 import java.util.TreeMap;
@@ -42,6 +41,7 @@
 import org.apache.cayenne.configuration.ConfigurationTree;
 import org.apache.cayenne.configuration.DataChannelDescriptor;
 import org.apache.cayenne.configuration.DataChannelDescriptorLoader;
+import org.apache.cayenne.configuration.xml.ProjectVersion;
 import org.apache.cayenne.di.Inject;
 import org.apache.cayenne.map.DataMap;
 import org.apache.cayenne.map.EntityResolver;
@@ -61,8 +61,6 @@
 import org.xml.sax.XMLReader;
 import org.xml.sax.helpers.DefaultHandler;
 
-import static org.apache.cayenne.util.Util.isBlank;
-
 /**
  *
  * Upgrade service sequence is following:
@@ -89,10 +87,9 @@ public class DefaultUpgradeService implements UpgradeService {
 
     private static final Logger logger = LoggerFactory.getLogger(DefaultUpgradeService.class);
 
-    public static final String UNKNOWN_VERSION = "0";
-    public static final String MIN_SUPPORTED_VERSION = "6";
+    public static final ProjectVersion MIN_SUPPORTED_VERSION = ProjectVersion.V6;
 
-    TreeMap<String, UpgradeHandler> handlers = new TreeMap<>(VersionComparator.INSTANCE);
+    TreeMap<ProjectVersion, UpgradeHandler> handlers = new TreeMap<>();
 
     @Inject
     private ProjectSaver projectSaver;
@@ -101,7 +98,7 @@ public class DefaultUpgradeService implements UpgradeService {
     private DataChannelDescriptorLoader loader;
 
     public DefaultUpgradeService(@Inject List<UpgradeHandler> handlerList) {
-        for(UpgradeHandler handler : handlerList) {
+        for (UpgradeHandler handler : handlerList) {
             handlers.put(handler.getVersion(), handler);
         }
     }
@@ -110,44 +107,34 @@ public DefaultUpgradeService(@Inject List<UpgradeHandler> handlerList) {
     public UpgradeMetaData getUpgradeType(Resource resource) {
         UpgradeMetaData metaData = new UpgradeMetaData();
 
-        String version = loadProjectVersion(resource);
-        metaData.setProjectVersion(version);
-        metaData.setSupportedVersion(String.valueOf(Project.VERSION));
+        ProjectVersion version = loadProjectVersion(resource);
+        metaData.setProjectVersion(version.getAsString());
+        metaData.setSupportedVersion(ProjectVersion.getCurrent().getAsString());
 
-        int c1 = VersionComparator.INSTANCE.compare(version, MIN_SUPPORTED_VERSION);
-        if (c1 < 0) {
-            metaData.setIntermediateUpgradeVersion(MIN_SUPPORTED_VERSION);
+        if (version.compareTo(MIN_SUPPORTED_VERSION) < 0) {
+            metaData.setIntermediateUpgradeVersion(MIN_SUPPORTED_VERSION.getAsString());
             metaData.setUpgradeType(UpgradeType.INTERMEDIATE_UPGRADE_NEEDED);
             return metaData;
         }
 
-        int c2 = VersionComparator.INSTANCE.compare(String.valueOf(Project.VERSION), version);
-        if (c2 < 0) {
+        int comparison = ProjectVersion.getCurrent().compareTo(version);
+        if (comparison < 0) {
             metaData.setUpgradeType(UpgradeType.DOWNGRADE_NEEDED);
-        } else if (c2 == 0) {
+        } else if (comparison == 0) {
             metaData.setUpgradeType(UpgradeType.UPGRADE_NOT_NEEDED);
         } else {
             metaData.setUpgradeType(UpgradeType.UPGRADE_NEEDED);
         }
         return metaData;
     }
 
-    protected List<UpgradeHandler> getHandlersForVersion(String version) {
-        boolean found = MIN_SUPPORTED_VERSION.equals(version);
+    protected List<UpgradeHandler> getHandlersForVersion(ProjectVersion version) {
         List<UpgradeHandler> handlerList = new ArrayList<>();
-
-        for(Map.Entry<String, UpgradeHandler> entry : handlers.entrySet()) {
-            if(entry.getKey().equals(version)) {
-                found = true;
-                continue;
+        for (Map.Entry<ProjectVersion, UpgradeHandler> entry : handlers.entrySet()) {
+            if(entry.getKey().compareTo(version) > 0) {
+                handlerList.add(entry.getValue());
             }
-            if(!found) {
-                continue;
-            }
-
-            handlerList.add(entry.getValue());
         }
-
         return handlerList;
     }
 
@@ -263,7 +250,7 @@ protected void saveDocument(UpgradeUnit upgradeUnit) {
      * A default method for quick extraction of the project version from an XML
      * file.
      */
-    protected String loadProjectVersion(Resource resource) {
+    protected ProjectVersion loadProjectVersion(Resource resource) {
 
         RootTagHandler rootHandler = new RootTagHandler();
         URL url = resource.getURL();
@@ -278,44 +265,7 @@ protected String loadProjectVersion(Resource resource) {
             throw new ConfigurationException("Error reading configuration from %s", e, url);
         }
 
-        return rootHandler.projectVersion != null ? rootHandler.projectVersion : UNKNOWN_VERSION;
-    }
-
-    protected static double decodeVersion(String version) {
-        if (version == null || isBlank(version)) {
-            return 0;
-        }
-
-        // leave the first dot, and treat remaining as a fraction
-        // remove all non digit chars
-        StringBuilder buffer = new StringBuilder(version.length());
-        boolean dotProcessed = false;
-        for (int i = 0; i < version.length(); i++) {
-            char nextChar = version.charAt(i);
-            if (nextChar == '.' && !dotProcessed) {
-                dotProcessed = true;
-                buffer.append('.');
-            } else if (Character.isDigit(nextChar)) {
-                buffer.append(nextChar);
-            }
-        }
-
-        return Double.parseDouble(buffer.toString());
-    }
-
-    private static class VersionComparator implements Comparator<String> {
-
-        private static final VersionComparator INSTANCE = new VersionComparator();
-
-        @Override
-        public int compare(String o1, String o2) {
-            if (o1.equals(o2)) {
-                return 0;
-            }
-            double v1Double = decodeVersion(o1);
-            double v2Double = decodeVersion(o2);
-            return v1Double < v2Double ? -1 : 1;
-        }
+        return ProjectVersion.fromString(rootHandler.projectVersion);
     }
 
     class RootTagHandler extends DefaultHandler {

cayenne-project/src/main/java/org/apache/cayenne/project/upgrade/handlers/UpgradeHandler.java

@@ -25,6 +25,8 @@
 import javax.xml.xpath.XPathFactory;
 
 import org.apache.cayenne.configuration.DataChannelDescriptor;
+import org.apache.cayenne.configuration.xml.ProjectVersion;
+import org.apache.cayenne.configuration.xml.Schema;
 import org.apache.cayenne.project.upgrade.UpgradeUnit;
 import org.w3c.dom.Element;
 import org.w3c.dom.NodeList;
@@ -58,7 +60,7 @@ public interface UpgradeHandler {
     /**
      * @return target version for this handler
      */
-    String getVersion();
+    ProjectVersion getVersion();
 
     /**
      * Process DOM for the project root file (e.g. cayenne-project.xml)
@@ -84,13 +86,14 @@ default void processModel(DataChannelDescriptor dataChannelDescriptor) {
      */
     default void updateDomainSchemaAndVersion(UpgradeUnit upgradeUnit) {
         Element domain = upgradeUnit.getDocument().getDocumentElement();
+        ProjectVersion version = getVersion();
         // update schema
-        domain.setAttribute("xmlns","http://cayenne.apache.org/schema/"+getVersion()+"/domain");
+        domain.setAttribute("xmlns", Schema.buildNamespace(version, "domain"));
         domain.setAttribute("xmlns:xsi","http://www.w3.org/2001/XMLSchema-instance");
-        domain.setAttribute("xsi:schemaLocation", "http://cayenne.apache.org/schema/"+getVersion()+"/domain " +
-                "https://cayenne.apache.org/schema/"+getVersion()+"/domain.xsd");
+        domain.setAttribute("xsi:schemaLocation", Schema.buildNamespace(version, "domain") + " " +
+                Schema.buildSchemaLocation(version, "domain"));
         // update version
-        domain.setAttribute("project-version", getVersion());
+        domain.setAttribute("project-version", version.getAsString());
     }
 
     /**
@@ -99,12 +102,13 @@ default void updateDomainSchemaAndVersion(UpgradeUnit upgradeUnit) {
      */
     default void updateDataMapSchemaAndVersion(UpgradeUnit upgradeUnit) {
         Element dataMap = upgradeUnit.getDocument().getDocumentElement();
+        ProjectVersion version = getVersion();
         // update schema
-        dataMap.setAttribute("xmlns","http://cayenne.apache.org/schema/"+getVersion()+"/modelMap");
-        dataMap.setAttribute("xsi:schemaLocation", "http://cayenne.apache.org/schema/"+getVersion()+"/modelMap " +
-                "https://cayenne.apache.org/schema/"+getVersion()+"/modelMap.xsd");
+        dataMap.setAttribute("xmlns", Schema.buildNamespace(version, "modelMap"));
+        dataMap.setAttribute("xsi:schemaLocation", Schema.buildNamespace(version, "modelMap") + " " +
+                Schema.buildSchemaLocation(version, "modelMap"));
         // update version
-        dataMap.setAttribute("project-version", getVersion());
+        dataMap.setAttribute("project-version", version.getAsString());
     }
 
     /**
@@ -123,7 +127,7 @@ default void updateExtensionSchema(UpgradeUnit upgradeUnit, String extension) {
         }
         for (int j = 0; j < nodes.getLength(); j++) {
             Element element = (Element) nodes.item(j);
-            element.setAttribute("xmlns", "http://cayenne.apache.org/schema/"+getVersion()+"/"+extension.toLowerCase());
+            element.setAttribute("xmlns", Schema.buildNamespace(getVersion(), extension.toLowerCase()));
         }
     }
 }

cayenne-project/src/main/java/org/apache/cayenne/project/upgrade/handlers/UpgradeHandler_V10.java

@@ -19,6 +19,7 @@
 
 package org.apache.cayenne.project.upgrade.handlers;
 
+import org.apache.cayenne.configuration.xml.ProjectVersion;
 import org.apache.cayenne.project.upgrade.UpgradeUnit;
 
 /**
@@ -32,8 +33,8 @@
 public class UpgradeHandler_V10 implements UpgradeHandler {
 
     @Override
-    public String getVersion() {
-        return "10";
+    public ProjectVersion getVersion() {
+        return ProjectVersion.V10;
     }
 
     @Override