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  1. ZK
  2. ZK-1537

NPE when listbox add to selection in paging mold (CE)

    Details

    • Type: Bug
    • Status: Closed
    • Priority: Normal
    • Resolution: Fixed
    • Affects Version/s: 6.5.1
    • Fix Version/s: 6.5.2
    • Component/s: Components
    • Labels:
      None

      Description

      (only when listbox + CE) EE doesn't have this issue
      the code is simulating mvvm behavior

      <zk>
      	<label multiline="true">
      (only when listbox + CE) EE doesn't have this issue
      the code is simulating mvvm behavior
      	1.chick addToSelection you should see a item A add to next page without an exception
      	2.this exception cause by a wrong implementation of object's hashcode()
      	3.should consider to avoid this exception (eat at org.zkoss.zul.Listbox.setSelectedIndex(Listbox.java:929)(need to check side effect)
      	  or throw meaningful exception(better)
      	</label>
      	<div width="400px" >
      		<listbox id="listbox" mold="paging" pageSize="10">
      			<listhead>
      				<listheader label="name" />
      			</listhead>
      			<template name="model" >
      				<listitem>
      					<listcell label="${each.name}" />
      				</listitem>
      			</template>
      		</listbox>
      		<button label="addToSelection" onClick="addToSelection()"/>
      	</div>
      <zscript><![CDATA[
      	class Item {
      		String name;
      		public Item() {
      			
      		}
      		public Item(String name) {
      			this.name = name;
      		}
      
      		public String getName() {
      			return name;
      		}
      
      		public void setName(String name) {
      			this.name = name;
      		}
      		
      		public int hashCode() {
      			final int prime = 31;
      			int result = 1;
      			result = prime * result + ((name == null) ? 0 : name.hashCode());
      			return result;
      		}
      
      		
      		public boolean equals(Object obj) {
      			if (this == obj)
      				return true;
      			if (obj == null)
      				return false;
      			if (!(obj instanceof Item))
      				return false;
      			Item other = (Item) obj;
      			if (name == null) {
      				if (other.name != null)
      					return false;
      			} else if (!name.equals(other.name))
      				return false;
      			return true;
      		}
      		
      	}
      	List itemList = new LinkedList();
      	for (int i = 0; i < 10; i++) {
      		itemList.add(new Item("item " + i));
      	}
      	ListModelList listModelList = new ListModelList(itemList,true);//if use live list
      	listbox.setModel(listModelList);
      	
      	//1.an item is not in collection yet, however, it already in the selection
      	Item n = new Item();
      	listModelList.addSelection(n);//un non in list selection
      
      	public void addToSelection() {
      		//2.after the value changed of the item
      		//the wrong imple of item hash cause this exception
      		n.setName("A");
      		itemList.add(n);
      		listModelList.addSelection(n);
      		listbox.setModel(listModelList);
      	}
      ]]>
      </zscript>
      </zk>
      

      >>java.lang.NullPointerException
      >> at org.zkoss.zul.Listbox.setSelectedIndex(Listbox.java:929)
      >> at org.zkoss.zul.Listbox.onListDataChange(Listbox.java:2531)
      >> at org.zkoss.zul.Listbox.access$17(Listbox.java:2521)
      >> at org.zkoss.zul.Listbox$4.onChange(Listbox.java:461)
      >> at org.zkoss.zul.AbstractListModel.fireEvent(AbstractListModel.java:61)
      >> at org.zkoss.zul.ListModelList.fireSelectionEvent(ListModelList.java:438)
      >> at org.zkoss.zul.AbstractListModel.addToSelection(AbstractListModel.java:130)
      >> at org.zkoss.zul.ListModelList.addSelection(ListModelList.java:445)
      >> at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
      >> at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
      >> at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
      >> at java.lang.reflect.Method.invoke(Method.java:597)
      >> at bsh.Reflect.invokeMethod(Unknown Source)
      >> at bsh.Reflect.invokeObjectMethod(Unknown Source)
      >> at bsh.Name.invokeMethod(Unknown Source)
      >> at bsh.BSHMethodInvocation.eval(Unknown Source)
      >> at bsh.BSHPrimaryExpression.eval(Unknown Source)
      >> at bsh.BSHPrimaryExpression.eval(Unknown Source)
      >> at bsh.BSHBlock.evalBlock(Unknown Source)
      >> at bsh.BSHBlock.eval(Unknown Source)
      >> at bsh.BshMethod.invokeImpl(Unknown Source)
      >> at bsh.BshMethod.invoke(Unknown Source)
      >> at bsh.BshMethod.invoke(Unknown Source)
      >> at bsh.Name.invokeLocalMethod(Unknown Source)
      >> at bsh.Name.invokeMethod(Unknown Source)
      >> at bsh.BSHMethodInvocation.eval(Unknown Source)
      >> at bsh.BSHPrimaryExpression.eval(Unknown Source)
      >> at bsh.BSHPrimaryExpression.eval(Unknown Source)
      >> at bsh.Interpreter.eval(Unknown Source)
      >> at bsh.Interpreter.eval(Unknown Source)
      >> at org.zkoss.zk.scripting.bsh.BSHInterpreter.exec(BSHInterpreter.java:131)
      >> at org.zkoss.zk.scripting.util.GenericInterpreter.interpret(GenericInterpreter.java:328)
      >> at org.zkoss.zk.ui.impl.PageImpl.interpret(PageImpl.java:875)
      >> at org.zkoss.zk.ui.AbstractComponent.service(AbstractComponent.java:2701)
      >> at org.zkoss.zk.ui.AbstractComponent.service(AbstractComponent.java:2654)
      >> at org.zkoss.zk.ui.impl.EventProcessor.process(EventProcessor.java:136)
      >> at org.zkoss.zk.ui.impl.UiEngineImpl.processEvent(UiEngineImpl.java:1710)
      >> at org.zkoss.zk.ui.impl.UiEngineImpl.process(UiEngineImpl.java:1495)
      >> at org.zkoss.zk.ui.impl.UiEngineImpl.execUpdate(UiEngineImpl.java:1205)
      >> at org.zkoss.zk.au.http.DHtmlUpdateServlet.process(DHtmlUpdateServlet.java:583)
      >> at org.zkoss.zk.au.http.DHtmlUpdateServlet.doGet(DHtmlUpdateServlet.java:481)
      >> at org.zkoss.zk.au.http.DHtmlUpdateServlet.doPost(DHtmlUpdateServlet.java:489)
      >> at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
      >> at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)
      >> at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)
      >> at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:401)
      >> at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)
      >> at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)
      >> at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:766)
      >> at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:450)
      >> at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
      >> at org.mortbay.jetty.Server.handle(Server.java:326)
      >> at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)
      >> at org.mortbay.jetty.HttpConnection$RequestHandler.content(HttpConnection.java:945)
      >> at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:756)
      >> at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:218)
      >> at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)
      >> at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:410)
      >> at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)

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              • Assignee:
                vincentjian vincentjian
                Reporter:
                dennis dennis
              • Votes:
                1 Vote for this issue
                Watchers:
                1 Start watching this issue

                Dates

                • Created:
                  Updated:
                  Resolved: