问题
An issue has appeared for our code after updating to SDN4:
java.lang.ClassCastException: java.util.HashMap cannot be cast to com.example.server.model.neo4j.node.Item
at com.example.server.service.relationship.friend.FriendRelationshipService.getSkillUuidByPotentialSkillName (FriendRelationshipService.java:257)
at com.example.server.service.relationship.friend.FriendRelationshipService.createFriendRequestRelationshipBetweenPeople(FriendRelationshipService.java:211)
at com.example.server.service.relationship.friend.FriendRelationshipService.sendFriendRequestHelper(FriendRelationshipService.java:171)
at com.example.server.service.relationship.friend.FriendRelationshipService.sendFriendRequest(FriendRelationshipService.java:81)
at com.example.server.test.integration.controller.api.friends.TestLoadFriendRequestsBothWays.testLoadFriendRequestsBothWaysNullCommonSkillNameSupplied(TestLoadFriendRequestsBothWays.java:184)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
at org.springframework.test.context.junit4.statements.RunBeforeTestMethodCallbacks.evaluate(RunBeforeTestMethodCallbacks.java:74)
at org.springframework.test.context.junit4.statements.RunAfterTestMethodCallbacks.evaluate(RunAfterTestMethodCallbacks.java:85)
at org.springframework.test.context.junit4.statements.SpringRepeat.evaluate(SpringRepeat.java:86)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:243)
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:88)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70)
at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:182)
at org.junit.runners.Suite.runChild(Suite.java:128)
at org.junit.runners.Suite.runChild(Suite.java:27)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
at org.junit.runners.Suite.runChild(Suite.java:128)
at org.junit.runners.Suite.runChild(Suite.java:27)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
at org.junit.runners.Suite.runChild(Suite.java:128)
at org.junit.runners.Suite.runChild(Suite.java:27)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:459)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:675)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:382)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:192)
The code that causes the exception is below:
Iterable<Item> items = itemRepository.findItemsByPerson(person.getUuid(), new Pagination(0, 1));
for(Item item : items) { // Stacktrace leads the issue to here.
currItem = item;
break;
}
Perhaps this is something to do with the for-each loop, as this appears to be the case for other parts of the code which also shows this issue.
Update 05/08/2015: The Item class is as below:
@NodeEntity
public class Item extends Entity implements Packageable {
private String name;
private String shortDescription;
private boolean isUserCreatedItem = false;
private double timestamp;
@Relationship(type = "CREATED_BY")
private Person creator;
public Item() {
}
/**
* This should be called after instantiating a new node (indicating a new node is to be added to the database)
*/
@Override
public void init() {
super.init();
}
// Other methods here
}
And the Entity class:
public abstract class Entity {
private String uuid;
@GraphId private Long id;
public void init() {
// generate the UUID
if(uuid == null) {
uuid = Util.generateUUID();
}
}
}
The repository query method:
@Query("MATCH (item)<-[:HAS_ITEM]-(you {uuid: {0}}) "
+ "RETURN DISTINCT item "
+ "ORDER BY item.name")
Iterable<Item> findItemsByPerson(String personUuid);
Any help would be much appreciated.
Cheers
回答1:
This is a bug which you can track at https://jira.spring.io/browse/DATAGRAPH-727
As a temporary workaround, please use a Collection instead of an Iterable.
来源：https://stackoverflow.com/questions/31821619/sdn4-classcastexception-java-util-hashmap-cannot-be-cast-to-entitynode