From c88023973ee6eeb268f2bfce2719d4ad83734b50 Mon Sep 17 00:00:00 2001
From: Michael Hunger <github@jexp.de>
Date: Tue, 22 Feb 2011 23:22:16 +0100
Subject: [PATCH] fixed bug with lazy evaluation and non-returning PathMapper
 (i.e PathCallbackHandler)

---
 .../neo4j/template/IterationController.java   |  4 +-
 .../graph/neo4j/template/Neo4jTemplate.java   | 32 +-----------
 .../data/graph/neo4j/template/PathMapper.java |  4 +-
 .../neo4j/template/PathMappingIterator.java   | 49 +++++++++++++++++++
 .../Neo4jGraphRecommendationTest-context.xml  | 22 ++++-----
 .../test/resources/spring-tx-text-context.xml |  7 ++-
 6 files changed, 68 insertions(+), 50 deletions(-)
 create mode 100644 spring-data-neo4j/src/main/java/org/springframework/data/graph/neo4j/template/PathMappingIterator.java

diff --git a/spring-data-neo4j/src/main/java/org/springframework/data/graph/neo4j/template/IterationController.java b/spring-data-neo4j/src/main/java/org/springframework/data/graph/neo4j/template/IterationController.java
index 5b5f1d136..f77c6ff11 100644
--- a/spring-data-neo4j/src/main/java/org/springframework/data/graph/neo4j/template/IterationController.java
+++ b/spring-data-neo4j/src/main/java/org/springframework/data/graph/neo4j/template/IterationController.java
@@ -5,8 +5,8 @@ package org.springframework.data.graph.neo4j.template;
 * @since 22.02.11
 */
 public interface IterationController {
-    public enum IterationControl {
+    public enum IterationMode {
         LAZY, EAGER, EAGER_STOP_ON_NULL
     }
-    IterationControl iterateAs();
+    IterationMode getIterationMode();
 }
diff --git a/spring-data-neo4j/src/main/java/org/springframework/data/graph/neo4j/template/Neo4jTemplate.java b/spring-data-neo4j/src/main/java/org/springframework/data/graph/neo4j/template/Neo4jTemplate.java
index c40d9edc8..eb5690389 100644
--- a/spring-data-neo4j/src/main/java/org/springframework/data/graph/neo4j/template/Neo4jTemplate.java
+++ b/spring-data-neo4j/src/main/java/org/springframework/data/graph/neo4j/template/Neo4jTemplate.java
@@ -29,7 +29,7 @@ import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
 
-import static org.springframework.data.graph.neo4j.template.IterationController.IterationControl.EAGER_STOP_ON_NULL;
+import static org.springframework.data.graph.neo4j.template.IterationController.IterationMode.EAGER_STOP_ON_NULL;
 
 public class Neo4jTemplate implements Neo4jOperations {
 
@@ -216,37 +216,9 @@ public class Neo4jTemplate implements Neo4jOperations {
     }
 
     private <T> Iterable<T> mapPaths(final Iterable<Path> paths, final PathMapper<T> pathMapper) {
-        assert paths != null;
-        assert pathMapper != null;
-        IterationController.IterationControl control = getIterationControl(pathMapper);
-        switch (control) {
-            case EAGER:
-            case EAGER_STOP_ON_NULL:
-                List<T> result=new ArrayList<T>();
-                for (Path path : paths) {
-                    T mapped = pathMapper.mapPath(path);
-                    if (mapped==null && control== EAGER_STOP_ON_NULL) break;
-                    result.add(mapped);
-                }
-                return result;
-            case LAZY:
-                return new IterableWrapper<T, Path>(paths) {
-                    @Override
-                    protected T underlyingObjectToObject(Path path) {
-                        return pathMapper.mapPath(path);
-                    }
-                };
-            default: throw new IllegalStateException("Unknown IterationControl "+control);
-        }
+        return new PathMappingIterator().mapPaths(paths,pathMapper);
     }
 
-    private <T> IterationController.IterationControl getIterationControl(PathMapper<T> pathMapper) {
-        if (pathMapper instanceof IterationController) {
-            IterationController.IterationControl result = ((IterationController) pathMapper).iterateAs();
-            if (result!=null) return result;
-        }
-        return IterationController.IterationControl.LAZY;
-    }
 
     @Override
     public <T> Iterable<T> traverseNext(Node startNode, final PathMapper<T> pathMapper, RelationshipType relationshipType, Direction direction) {
diff --git a/spring-data-neo4j/src/main/java/org/springframework/data/graph/neo4j/template/PathMapper.java b/spring-data-neo4j/src/main/java/org/springframework/data/graph/neo4j/template/PathMapper.java
index d194ab05b..95d703eea 100644
--- a/spring-data-neo4j/src/main/java/org/springframework/data/graph/neo4j/template/PathMapper.java
+++ b/spring-data-neo4j/src/main/java/org/springframework/data/graph/neo4j/template/PathMapper.java
@@ -20,8 +20,8 @@ public interface PathMapper<T> {
         }
 
         @Override
-        public IterationControl iterateAs() {
-            return IterationController.IterationControl.EAGER;
+        public IterationMode getIterationMode() {
+            return IterationMode.EAGER;
         }
     }
 }
diff --git a/spring-data-neo4j/src/main/java/org/springframework/data/graph/neo4j/template/PathMappingIterator.java b/spring-data-neo4j/src/main/java/org/springframework/data/graph/neo4j/template/PathMappingIterator.java
new file mode 100644
index 000000000..b1005dae4
--- /dev/null
+++ b/spring-data-neo4j/src/main/java/org/springframework/data/graph/neo4j/template/PathMappingIterator.java
@@ -0,0 +1,49 @@
+package org.springframework.data.graph.neo4j.template;
+
+import org.neo4j.graphdb.Path;
+import org.neo4j.helpers.collection.IterableWrapper;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import static org.springframework.data.graph.neo4j.template.IterationController.IterationMode.EAGER_STOP_ON_NULL;
+
+/**
+ * @author mh
+ * @since 22.02.11
+ */
+public class PathMappingIterator {
+    <T> Iterable<T> mapPaths(final Iterable<Path> paths, final PathMapper<T> pathMapper) {
+        assert paths != null;
+        assert pathMapper != null;
+        IterationController.IterationMode mode = getIterationControl(pathMapper);
+        switch (mode) {
+            case EAGER:
+            case EAGER_STOP_ON_NULL:
+                List<T> result = new ArrayList<T>();
+                for (Path path : paths) {
+                    T mapped = pathMapper.mapPath(path);
+                    if (mapped == null && mode == EAGER_STOP_ON_NULL) break;
+                    result.add(mapped);
+                }
+                return result;
+            case LAZY:
+                return new IterableWrapper<T, Path>(paths) {
+                    @Override
+                    protected T underlyingObjectToObject(Path path) {
+                        return pathMapper.mapPath(path);
+                    }
+                };
+            default:
+                throw new IllegalStateException("Unknown IterationControl " + mode);
+        }
+    }
+
+    private <T> IterationController.IterationMode getIterationControl(PathMapper<T> pathMapper) {
+        if (pathMapper instanceof IterationController) {
+            IterationController.IterationMode result = ((IterationController) pathMapper).getIterationMode();
+            if (result != null) return result;
+        }
+        return IterationController.IterationMode.LAZY;
+    }
+}
diff --git a/spring-data-neo4j/src/test/resources/org/springframework/data/graph/neo4j/partial/Neo4jGraphRecommendationTest-context.xml b/spring-data-neo4j/src/test/resources/org/springframework/data/graph/neo4j/partial/Neo4jGraphRecommendationTest-context.xml
index 7569fb632..847833ad3 100644
--- a/spring-data-neo4j/src/test/resources/org/springframework/data/graph/neo4j/partial/Neo4jGraphRecommendationTest-context.xml
+++ b/spring-data-neo4j/src/test/resources/org/springframework/data/graph/neo4j/partial/Neo4jGraphRecommendationTest-context.xml
@@ -143,25 +143,23 @@
             <bean class="org.springframework.orm.jpa.JpaTransactionManager" id="jpaTransactionManager">
                 <property name="entityManagerFactory" ref="entityManagerFactory"/>
             </bean>
-			 <!--bean class="org.springframework.jdbc.datasource.DataSourceTransactionManager" >
-			 	<property name="dataSource" ref="dataSource"/>
-			 </bean-->
 			<bean
 			    class="org.springframework.transaction.jta.JtaTransactionManager">
-			    <property name="transactionManager" ref="neo4jTransactionManagerService" />
-			    <property name="userTransaction" ref="neo4jUserTransactionService" />
+			    <property name="transactionManager">
+                    <bean class="org.neo4j.kernel.impl.transaction.SpringTransactionManager">
+                        <constructor-arg ref="graphDatabaseService" />
+                    </bean>
+			    </property>
+			    <property name="userTransaction">
+                    <bean  class="org.neo4j.kernel.impl.transaction.UserTransactionImpl">
+                        <constructor-arg ref="graphDatabaseService" />
+                    </bean>
+			    </property>
 			</bean>
             </list>
 		</constructor-arg>
 	</bean>
 
-	<bean id="neo4jTransactionManagerService" class="org.neo4j.kernel.impl.transaction.SpringTransactionManager" >
-	  <constructor-arg index="0" ref="graphDatabaseService" />
-	</bean>
-	
-	<bean id="neo4jUserTransactionService" class="org.neo4j.kernel.impl.transaction.UserTransactionImpl">
-	    <constructor-arg index="0" ref="graphDatabaseService" />
-	</bean>
 
 	<bean class="org.springframework.jdbc.datasource.DriverManagerDataSource" id="dataSource">
         <property name="driverClassName" value="${database.driverClassName}"/>
diff --git a/spring-data-neo4j/src/test/resources/spring-tx-text-context.xml b/spring-data-neo4j/src/test/resources/spring-tx-text-context.xml
index abf7dccf6..a31f4b63d 100644
--- a/spring-data-neo4j/src/test/resources/spring-tx-text-context.xml
+++ b/spring-data-neo4j/src/test/resources/spring-tx-text-context.xml
@@ -16,12 +16,11 @@
 
     <context:annotation-config />
     <context:spring-configured/>
-    <bean id="jotm" class="org.springframework.data.graph.neo4j.transaction.JotmFactoryBean">
-        <!--property name="jotmHome" value="target/classes/jotm"/-->
-    </bean>
 
     <bean id="transactionManager" class="org.springframework.transaction.jta.JtaTransactionManager">
-        <property name="transactionManager" ref="jotm"/>
+        <property name="transactionManager">
+            <bean id="jotm" class="org.springframework.data.graph.neo4j.transaction.JotmFactoryBean"/>
+        </property>
     </bean>
 
     <bean class="org.neo4j.kernel.EmbeddedGraphDatabase" destroy-method="shutdown">