java - 通过Java配置JanusGraph以使用Lucene

我正在尝试使用以下代码连接到JanusGraph：

Graph graph = GraphFactory.open(new PropertiesConfiguration("janusgraph.propertes");

我的janusgraph.properties文件如下所示：

gremlin.graph=org.janusgraph.core.JanusGraphFactory
storage.backend=hbase
storage.hostname=127.0.0.1

cache.db-cache = true
cache.db-cache-clean-wait = 20
cache.db-cache-time = 180000
cache.db-cache-size = 0.5

index.janusgraph-index.backend=lucene

但是，当我尝试连接时，出现以下错误：

Exception in thread "Thread-4" java.lang.RuntimeException: GraphFactory could not instantiate this Graph implementation [class org.janusgraph.core.JanusGraphFactory]
    at org.apache.tinkerpop.gremlin.structure.util.GraphFactory.open(GraphFactory.java:82)
    at org.apache.tinkerpop.gremlin.structure.util.GraphFactory.open(GraphFactory.java:70)
    at uk.gov.nca.cdp.graphutils.server.controllers.MergeGraph.lambda$merge$0(MergeGraph.java:26)
    at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.reflect.InvocationTargetException
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.apache.tinkerpop.gremlin.structure.util.GraphFactory.open(GraphFactory.java:78)
    ... 3 more
Caused by: java.lang.IllegalArgumentException: Could not find implementation class: org.janusgraph.diskstorage.es.ElasticSearchIndex
    at org.janusgraph.util.system.ConfigurationUtil.instantiate(ConfigurationUtil.java:61)
    at org.janusgraph.diskstorage.Backend.getImplementationClass(Backend.java:477)
    at org.janusgraph.diskstorage.Backend.getIndexes(Backend.java:464)
    at org.janusgraph.diskstorage.Backend.<init>(Backend.java:149)
    at org.janusgraph.graphdb.configuration.GraphDatabaseConfiguration.getBackend(GraphDatabaseConfiguration.java:1897)
    at org.janusgraph.graphdb.database.StandardJanusGraph.<init>(StandardJanusGraph.java:136)
    at org.janusgraph.core.JanusGraphFactory.open(JanusGraphFactory.java:164)
    at org.janusgraph.core.JanusGraphFactory.open(JanusGraphFactory.java:133)
    at org.janusgraph.core.JanusGraphFactory.open(JanusGraphFactory.java:113)
    ... 8 more
Caused by: java.lang.ClassNotFoundException: org.janusgraph.diskstorage.es.ElasticSearchIndex
    at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at org.springframework.boot.loader.LaunchedURLClassLoader.loadClass(LaunchedURLClassLoader.java:94)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    at java.lang.Class.forName0(Native Method)
    at java.lang.Class.forName(Class.java:264)
    at org.janusgraph.util.system.ConfigurationUtil.instantiate(ConfigurationUtil.java:56)
    ... 16 more

这听起来像是在尝试使用Elasticsearch而不是Lucene。如何正确配置它以使用Lucene？

最佳答案

您遇到的问题是您的配置未定义storage.hbase.table，因此使用了默认表名janusgraph（请参见JanusGraph configuration reference）。必须先前已使用Elasticsearch为索引提供程序创建了名为janusgraph的HBase表。 JanusGraph将其初始配置存储在HBase表中，因此，当您连接到janusgraph表时，它将从janusgraph表中读取旧属性。您应该：


删除现有的janusgraph HBase表。在HBase Shell中：disable 'janusgraph'; drop 'janusgraph';
通过设置storage.hbase.table=mygraph使用其他HBase表


如JanusGraph Lucene documentation中所述，Lucene索引后端在其配置中需要两个参数：


index.[X].backend=lucene
index.[X].directory=/data/searchindex


其中，[X]是索引的名称。您可以将其设置为与示例中常见的目录名称searchindex或search或问题中的janusgraph-index匹配。确保同时包含两个配置属性。

关于java - 通过Java配置JanusGraph以使用Lucene，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/47653285/