how i can solve this issue?
at org.dspace.discovery.SolrServiceImpl.cleanIndex(SolrServiceImpl.java:507)
at org.dspace.discovery.IndexClient.main(IndexClient.java:126)
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.dspace.app.launcher.ScriptLauncher.runOneCommand(ScriptLauncher.java:226)
at org.dspace.app.launcher.ScriptLauncher.main(ScriptLauncher.java:78)
at org.apache.solr.client.solrj.impl.HttpSolrServer.executeMethod(HttpSolrServer.java:559)
at org.apache.solr.client.solrj.impl.HttpSolrServer.request(HttpSolrServer.java:210)
at org.apache.solr.client.solrj.impl.HttpSolrServer.request(HttpSolrServer.java:206)
at org.apache.solr.client.solrj.request.QueryRequest.process(QueryRequest.java:91)
at org.apache.solr.client.solrj.SolrServer.query(SolrServer.java:301)
at org.dspace.discovery.SolrServiceImpl.cleanIndex(SolrServiceImpl.java:477)
... 7 more
Caused by: java.net.ConnectException: Connection refused
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:339)
at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:200)
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:182)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
at java.net.Socket.connect(Socket.java:579)
at org.apache.http.conn.scheme.PlainSocketFactory.connectSocket(PlainSocketFactory.java:117)
at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:177)
at org.apache.http.impl.conn.ManagedClientConnectionImpl.open(ManagedClientConnectionImpl.java:304)
at org.apache.http.impl.client.DefaultRequestDirector.tryConnect(DefaultRequestDirector.java:611)
at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:446)
at org.apache.http.impl.client.AbstractHttpClient.doExecute(AbstractHttpClient.java:863)
at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:82)
at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:106)
at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:57)
at org.apache.solr.client.solrj.impl.HttpSolrServer.executeMethod(HttpSolrServer.java:448)
... 12 more