at net.universia.commons.lucene.Engine.getQuery(Engine.java:340)
at net.universia.commons.lucene.Engine.getQuery(Engine.java:357)
at net.universia.commons.lucene.SearchEngine.getQuery(SearchEngine.java:107)
at net.universia.commons.lucene.SearchEngine.search(SearchEngine.java:102)
at net.universia.rayuela.lucene.search.SearchSCO.search(SearchSCO.java:24)
at net.universia.rayuela.actions.SearchAutorAction.executeLogic(SearchAutorAction.java:39)
at net.universia.rayuela.actions.RayuelaBaseAction.execute(RayuelaBaseAction.java:213)
at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:421)
at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:226)
at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1164)
at org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:397)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:114)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:91)
at com.caucho.server.dispatch.ServletFilterChain.doFilter(ServletFilterChain.java:103)
at com.caucho.server.cache.CacheFilterChain.doFilter(CacheFilterChain.java:194)
at com.caucho.server.webapp.WebAppFilterChain.doFilter(WebAppFilterChain.java:187)
at com.caucho.server.dispatch.ServletInvocation.service(ServletInvocation.java:266)
at com.caucho.server.hmux.HmuxRequest.handleRequest(HmuxRequest.java:435)
at com.caucho.server.port.TcpConnection.run(TcpConnection.java:678)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:721)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:643)
at java.lang.Thread.run(Thread.java:595)

Caused By: org.apache.lucene.queryParser.ParseException: Cannot parse ' ': Encountered "" at line 1, column 1. Was expecting one of: ... "+" ... "-" ... "(" ... "*" ... ... ... ... ... "[" ... "{" ... ... ... "*" ...
StackTrace:

at org.apache.lucene.queryParser.QueryParser.parse(QueryParser.java:181)
at net.universia.commons.lucene.Engine.getQuery(Engine.java:336)
at net.universia.commons.lucene.Engine.getQuery(Engine.java:357)
at net.universia.commons.lucene.SearchEngine.getQuery(SearchEngine.java:107)
at net.universia.commons.lucene.SearchEngine.search(SearchEngine.java:102)
at net.universia.rayuela.lucene.search.SearchSCO.search(SearchSCO.java:24)
at net.universia.rayuela.actions.SearchAutorAction.executeLogic(SearchAutorAction.java:39)
at net.universia.rayuela.actions.RayuelaBaseAction.execute(RayuelaBaseAction.java:213)
at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:421)
at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:226)
at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1164)
at org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:397)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:114)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:91)
at com.caucho.server.dispatch.ServletFilterChain.doFilter(ServletFilterChain.java:103)
at com.caucho.server.cache.CacheFilterChain.doFilter(CacheFilterChain.java:194)
at com.caucho.server.webapp.WebAppFilterChain.doFilter(WebAppFilterChain.java:187)
at com.caucho.server.dispatch.ServletInvocation.service(ServletInvocation.java:266)
at com.caucho.server.hmux.HmuxRequest.handleRequest(HmuxRequest.java:435)
at com.caucho.server.port.TcpConnection.run(TcpConnection.java:678)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:721)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:643)
at java.lang.Thread.run(Thread.java:595)