java.lang.StringIndexOutOfBoundsException：字符串索引超出范围：-1

Question

我正在尝试使用可拖动的可放置组件S. 这是我的代码：

<h:panelGrid columns="2" cellpadding="10">   
  <p:column>
    <p:fieldset id="belongTo" legend="Belong To" >  
      <p:dataGrid id="userGroups"
                  var="userGroup"
                  value="#{projectAdminisrationMB.selectedUserMemberOfGroups}"
                  columns="3">  
        <p:column>  
          <p:panel id="pnl1"
                   header="#{userGroup.name}"
                   style="text-align:center">
            <h:panelGrid columns="1" style="width:100%">  
              <p:graphicImage value="/images/group/adminGroup.gif"/> 
            </h:panelGrid>  
          </p:panel>  
          <p:draggable for="pnl1"
                       revert="true"
                       handle=".ui-panel-titlebar"
                       stack=".ui-panel"/>
        </p:column>  
      </p:dataGrid>  
    </p:fieldset>  
    <p:droppable for="belongTo"
                 tolerance="touch"
                 activeStyleClass="ui-state-highlight"
                 datasource="userNotGroups" >
      <p:ajax listener="#{projectAdminisrationMB.onExcludeFromGroupDrop}" />
    </p:droppable> 
  </p:column>
  <p:column>  
    <p:fieldset id="excludeFrom"
                legend="Exclude From"
                style="margin-top:20px">  
      <p:dataGrid id="userNotGroups"
                  var="userNotGroup"
                  value="#{projectAdminisrationMB.selectedUserNotMemberOfGroups}"
                  columns="3">  
        <p:column>  
          <p:panel id="pnl2"
                   header="#{userNotGroup.name}"
                   style="text-align:center">  
            <h:panelGrid columns="1" style="width:100%">  
              <p:graphicImage value="/images/grou/defaultGroup.gif"/> 
            </h:panelGrid>  
          </p:panel>  
          <p:draggable for="pnl2"
                       revert="true"
                       handle=".ui-panel-titlebar" 
                       stack=".ui-panel"/>  
        </p:column>  
      </p:dataGrid>  
    </p:fieldset>   
    <p:droppable for="excludeFrom"
                 tolerance="touch"
                 activeStyleClass="ui-state-highlight"
                 datasource="userGroups"  >  
      <p:ajax listener="#{projectAdminisrationMB.onBelongToGroupDrop}"  />  
    </p:droppable>  
  </p:column>
</h:panelGrid>

因此，当我触摸组件将其放到datagrid时，我收到此错误： 即使我只是移动组件，我也会得到它，组件是一个面板

java.lang.StringIndexOutOfBoundsException: String index out of range: -1
    at java.lang.String.substring(Unknown Source)
    at com.sun.faces.renderkit.ServerSideStateHelper.getState(ServerSideStateHelper.java:263)
    at com.sun.faces.renderkit.ResponseStateManagerImpl.getState(ResponseStateManagerImpl.java:97)
    at com.sun.faces.application.view.StateManagementStrategyImpl.restoreView(StateManagementStrategyImpl.java:217)
    at com.sun.faces.application.StateManagerImpl.restoreView(StateManagerImpl.java:177)
    at com.sun.faces.application.view.ViewHandlingStrategy.restoreView(ViewHandlingStrategy.java:119)
    at com.sun.faces.application.view.FaceletViewHandlingStrategy.restoreView(FaceletViewHandlingStrategy.java:438)
    at com.sun.faces.application.view.MultiViewHandler.restoreView(MultiViewHandler.java:144)
    at com.sun.faces.lifecycle.RestoreViewPhase.execute(RestoreViewPhase.java:182)
    at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:97)
    at com.sun.faces.lifecycle.RestoreViewPhase.doPhase(RestoreViewPhase.java:106)
    at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:114)
    at javax.faces.webapp.FacesServlet.service(FacesServlet.java:334)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:225)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:927)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1001)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:579)
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:310)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)