IDEA-27620 XML Catalog support: resolve system

xml/impl/src/com/intellij/javaee/XMLCatalogManager.java

@@ -17,6 +17,7 @@ package com.intellij.javaee;
 
 import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.openapi.util.io.FileUtil;
+import org.apache.xml.resolver.Catalog;
 import org.apache.xml.resolver.CatalogManager;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
@@ -73,7 +74,10 @@ public class XMLCatalogManager {
   @Nullable
   public String resolve(String uri) {
     try {
-      return myManager.getCatalog().resolvePublic(uri, null);
+      Catalog catalog = myManager.getCatalog();
+      if (catalog == null) return null;
+      String resolved = catalog.resolveSystem(uri);
+      return resolved == null ? catalog.resolvePublic(uri, null) : resolved;
     }
     catch (IOException e) {
       LOG.warn(e);

xml/tests/src/com/intellij/xml/XMLCatalogManagerTest.java

@@ -42,12 +42,18 @@ public class XMLCatalogManagerTest extends LightPlatformCodeInsightFixtureTestCa
     assertTrue(filePath, new File(new URI(filePath)).exists());
   }
 
-  public void testResolve() throws Exception {
+  public void testResolvePublic() throws Exception {
     String resolve = getManager().resolve("-//W3C//DTD XHTML 1.0 Strict//EN");
     assertNotNull(resolve);
     assertTrue(resolve, resolve.endsWith("/catalog/xhtml1-strict.dtd"));
   }
 
+  public void testResolveSystem() throws Exception {
+    String resolve = getManager().resolve("http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd");
+    assertNotNull(resolve);
+    assertTrue(resolve, resolve.endsWith("/catalog/xhtml1-strict.dtd"));
+  }
+
   private XMLCatalogManager getManager() throws IOException {
     return new XMLCatalogManager(getTestDataPath() + "catalog.properties");
   }

xml/tests/testData/catalog/catalog.xml

@@ -4,5 +4,6 @@
 
   <public publicId="-//W3C//DTD XHTML 1.0 Strict//EN"
     uri="xhtml1-strict.dtd"/>
-
+  <system systemId="http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"
+            uri="xhtml1-strict.dtd"/>
 </catalog>