1 files changed, 99 insertions, 0 deletions
diff --git a/sandbox/old/contrib/persistence/common/src/main/java/org/apache/tuscany/service/persistence/common/PersistenceUnitScanner.java b/sandbox/old/contrib/persistence/common/src/main/java/org/apache/tuscany/service/persistence/common/PersistenceUnitScanner.java
new file mode 100644
index 0000000000..00fd02b891
--- /dev/null
+++ b/sandbox/old/contrib/persistence/common/src/main/java/org/apache/tuscany/service/persistence/common/PersistenceUnitScanner.java
@@ -0,0 +1,99 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package org.apache.tuscany.service.persistence.common;
+
+import java.io.IOException;
+import java.net.URL;
+import java.util.Enumeration;
+import java.util.HashMap;
+import java.util.Map;
+
+import javax.persistence.spi.PersistenceUnitInfo;
+import javax.xml.parsers.DocumentBuilder;
+import javax.xml.parsers.DocumentBuilderFactory;
+import javax.xml.parsers.ParserConfigurationException;
+
+import org.w3c.dom.Document;
+import org.xml.sax.SAXException;
+
+/**
+ * Scans the classloader for the specified persistence unit.
+ *
+ * @version $Rev$ $Date$
+ */
+class PersistenceUnitScanner {
+
+    /** Cache of persistence unit info */
+    private Map<String, PersistenceUnitInfo> persistenceUnitInfos = new HashMap<String, PersistenceUnitInfo>();
+
+    /**
+     * Scans the lassloader for the specified persistence unit and creates 
+     * an immutable representation of the information present in the matching 
+     * persistence.xml file.
+     * 
+     * @param unitName Persistence unit name.
+     * @param classLoader Classloader to scan.
+     * @return Persistence unit information.
+     */
+    PersistenceUnitInfo getPersistenceUnitInfo(String unitName, ClassLoader classLoader) {
+
+        synchronized (persistenceUnitInfos) {
+            
+            if(persistenceUnitInfos.containsKey(unitName)) {
+                return persistenceUnitInfos.get(unitName);
+            }
+
+            try {
+
+                DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
+                DocumentBuilder db = dbf.newDocumentBuilder();
+
+                Enumeration<URL> persistenceUnitUrls = classLoader.getResources("META-INF/persistence.xml");
+                while (persistenceUnitUrls.hasMoreElements()) {
+
+                    URL persistenceUnitUrl = persistenceUnitUrls.nextElement();
+                    Document persistenceDom = db.parse(persistenceUnitUrl.openStream());
+
+                    String rootJarUrl = persistenceUnitUrl.toString();
+                    rootJarUrl = rootJarUrl.substring(0, rootJarUrl.lastIndexOf("META-INF"));
+
+                    PersistenceUnitInfo info = new TuscanyPersistenceUnitInfo(persistenceDom, classLoader, rootJarUrl);
+                    if (!unitName.equals(info.getPersistenceUnitName())) {
+                        continue;
+                    }
+
+                    persistenceUnitInfos.put(unitName, info);
+                    return info;
+
+                }
+            } catch (IOException ex) {
+                throw new TuscanyJpaException(ex);
+            } catch (ParserConfigurationException ex) {
+                throw new TuscanyJpaException(ex);
+            } catch (SAXException ex) {
+                throw new TuscanyJpaException(ex);
+            }
+
+        }
+
+        throw new TuscanyJpaException("Unabel to find persistence unit: " + unitName);
+
+    }
+
+}