OPENJPA-208 Added NoResultException and NonUniqueResultException to kernel to allow the identification of the case where a unique result was selected by either none or too many were found

git-svn-id: https://svn.apache.org/repos/asf/incubator/openjpa/trunk@526834 13f79535-47bb-0310-9956-ffa450edef68

openjpa-kernel/src/main/java/org/apache/openjpa/kernel/QueryImpl.java

@@ -51,6 +51,8 @@ import org.apache.openjpa.meta.JavaTypes;
 import org.apache.openjpa.meta.MetaDataRepository;
 import org.apache.openjpa.util.GeneralException;
 import org.apache.openjpa.util.InvalidStateException;
+import org.apache.openjpa.util.NonUniqueResultException;
+import org.apache.openjpa.util.NoResultException;
 import org.apache.openjpa.util.OpenJPAException;
 import org.apache.openjpa.util.UnsupportedException;
 import org.apache.openjpa.util.UserException;
@@ -1279,10 +1281,10 @@ public class QueryImpl
             if (next) {
                 single = rop.getResultObject();
                 if (range.end != range.start + 1 && rop.next())
-                    throw new InvalidStateException(_loc.get("not-unique",
+                    throw new NonUniqueResultException(_loc.get("not-unique",
                         _class, _query));
             } else if (_unique == Boolean.TRUE)
-                throw new InvalidStateException(_loc.get("no-result", 
+                throw new NoResultException(_loc.get("no-result", 
                     _class, _query));
 
             // if unique set to false, use collection

openjpa-kernel/src/main/java/org/apache/openjpa/util/NoResultException.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright 2006 The Apache Software Foundation.
+ *
+ * Licensed 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.openjpa.util;
+
+import org.apache.openjpa.lib.util.Localizer.Message;
+
+/**
+ * Exception type thrown when a query was configured to return
+ * a single result, and no result was found.
+ *
+ * @since 0.9.7
+ * @author Marc Prud'hommeaux
+ */
+public class NoResultException
+    extends InvalidStateException {
+
+    public NoResultException(Message msg) {
+        super(msg);
+    }
+
+    public NoResultException(Message msg, Object failed) {
+        super(msg);
+        setFailedObject(failed);
+    }
+
+    public int getSubtype() {
+        return NO_RESULT;
+    }
+}
+

openjpa-kernel/src/main/java/org/apache/openjpa/util/NonUniqueResultException.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright 2006 The Apache Software Foundation.
+ *
+ * Licensed 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.openjpa.util;
+
+import org.apache.openjpa.lib.util.Localizer.Message;
+
+/**
+ * Exception type thrown when a query was configured to return
+ * a single result, and multiple results were found.
+ *
+ * @since 0.9.7
+ * @author Marc Prud'hommeaux
+ */
+public class NonUniqueResultException
+    extends InvalidStateException {
+
+    public NonUniqueResultException(Message msg) {
+        super(msg);
+    }
+
+    public NonUniqueResultException(Message msg, Object failed) {
+        super(msg);
+        setFailedObject(failed);
+    }
+
+    public int getSubtype() {
+        return NON_UNIQUE_RESULT;
+    }
+}
+

openjpa-kernel/src/main/java/org/apache/openjpa/util/UserException.java

@@ -30,6 +30,8 @@ public class UserException
     public static final int INVALID_STATE = 2;
     public static final int NO_TRANSACTION = 3;
     public static final int CALLBACK = 4;
+    public static final int NO_RESULT = 5;
+    public static final int NON_UNIQUE_RESULT = 6;
 
     public UserException() {
     }

openjpa-persistence/src/main/java/org/apache/openjpa/persistence/PersistenceExceptions.java

@@ -173,6 +173,16 @@ public class PersistenceExceptions
                         (ke.getMessage(), getNestedThrowables(ke),
                             getFailedObject(ke), ke.isFatal());
                 break;
+            case UserException.NO_RESULT:
+                e = new org.apache.openjpa.persistence.NoResultException
+                    (ke.getMessage(), getNestedThrowables(ke),
+                        getFailedObject(ke), ke.isFatal());
+                break;
+            case UserException.NON_UNIQUE_RESULT:
+                e = new org.apache.openjpa.persistence.NonUniqueResultException
+                    (ke.getMessage(), getNestedThrowables(ke),
+                        getFailedObject(ke), ke.isFatal());
+                break;
             case UserException.INVALID_STATE:
                 e = new org.apache.openjpa.persistence.InvalidStateException
                     (ke.getMessage(), getNestedThrowables(ke),

openjpa-persistence/src/main/java/org/apache/openjpa/persistence/QueryImpl.java

@@ -281,26 +281,14 @@ public class QueryImpl
      */
     public Object getSingleResult() {
         _em.assertNotCloseInvoked();
-        Object ob = execute();
+        // temporarily set query to unique so that a single result is validated
-        if (!(ob instanceof List))
+        // and returned; unset again in case the user executes query again
-            return ob;
+        // via getResultList
-
+        _query.setUnique(true);
-        List res = (List) ob;
         try {
-            // don't use size() b/c can be inefficient under some LRS settings
+            return execute();
-            Iterator itr = res.iterator();
-            if (!itr.hasNext())
-                throw new NoResultException(_loc.get("no-results",
-                    _query.getQueryString()).getMessage(), null, null, false);
-
-            Object ret = itr.next();
-            if (itr.hasNext())
-                throw new NonUniqueResultException(_loc.get("mult-results",
-                    _query.getQueryString()).getMessage(), null, null, false);
-
-            return ret;
         } finally {
-            OpenJPAPersistence.close(res);
+            _query.setUnique(false);
         }
     }