0

以下代码片段：

GraphDatabaseService graphDb = new EmbeddedGraphDatabase("var/geo");
// Wrap it as a spatial db service
SpatialDatabaseService spatialDb = new SpatialDatabaseService(graphDb);
// Create the layer to store our spatial data
EditableLayer runningLayer = (EditableLayer) spatialDb.getOrCreateLayer("running", SimplePointEncoder.class, EditableLayerImpl.class, "lon:lat");

失败并出现错误：

Exception in thread "main" java.lang.ClassCastException: org.neo4j.collections.graphdb.impl.EmbeddedGraphDatabase cannot be cast to org.neo4j.kernel.GraphDatabaseAPI
at org.neo4j.cypher.ExecutionEngine.<init>(ExecutionEngine.scala:113)
at org.neo4j.cypher.javacompat.ExecutionEngine.<init>(ExecutionEngine.java:53)
at org.neo4j.cypher.javacompat.ExecutionEngine.<init>(ExecutionEngine.java:43)
at org.neo4j.collections.graphdb.ReferenceNodes.getReferenceNode(ReferenceNodes.java:60)
at org.neo4j.gis.spatial.SpatialDatabaseService.getSpatialRoot(SpatialDatabaseService.java:76)
at org.neo4j.gis.spatial.SpatialDatabaseService.getLayer(SpatialDatabaseService.java:108)
at org.neo4j.gis.spatial.SpatialDatabaseService.getOrCreateLayer(SpatialDatabaseService.java:202)
at com.bmt.contain.spatial.test.SpatialTest.main(SpatialTest.java:47)

我试图从这里获取示例代码来工作，我在下面包含了相关的导入语句，以防我以某种方式导入了错误版本的函数。

import org.neo4j.collections.graphdb.impl.EmbeddedGraphDatabase;

import org.neo4j.graphdb.GraphDatabaseService;

import org.neo4j.gis.spatial.EditableLayer;
import org.neo4j.gis.spatial.EditableLayerImpl;
import org.neo4j.gis.spatial.Layer;
import org.neo4j.gis.spatial.encoders.SimplePointEncoder;

有人可以给我建议吗？

此外，它的 2.0.1 用于 neo4j 和 v13 用于空间。

<dependency>
    <groupId>org.neo4j</groupId>
    <artifactId>neo4j-spatial</artifactId>
    <version>0.13-neo4j-2.0.1</version>
</dependency>
<dependency>
    <groupId>org.neo4j</groupId>
    <artifactId>neo4j</artifactId>
    <version>2.0.1</version>
</dependency>
4

1 回答 1

0

所以这个问题的答案是你需要使用

GraphDatabaseService graphDb = new GraphDatabaseFactory().newEmbeddedDatabase("var/geo");

代替

GraphDatabaseService graphDb = new EmbeddedGraphDatabase("var/geo");

这在引擎盖下的某个地方会创建一种不同类型的嵌入式 GDbS，它不会导致类转换异常。

于 2014-05-27T16:41:20.957 回答