json-lib转换

就集合转为json对象的时候出现如下错误
在下面的查询中查询出来的集合在debug模式下是这种效果下面是方法:public String findArea() {
Users user = (Users) this.getRequest().getSession()
.getAttribute("user"); String start = this.getRequest().getParameter("start");
String limit = this.getRequest().getParameter("limit"); List<Area> list = this.AreaService.getAreaByUser(user,
start != null ? Integer.valueOf(start)
: WebConstant.DEFAULT_START, limit != null ? Integer
.valueOf(limit) : WebConstant.DEFAULT_LIMIT);
int total = this.AreaService.getAreaCountByUser(user); JSONObject json = new JSONObject();
JsonConfig jconfig = new JsonConfig();
jconfig.setIgnoreDefaultExcludes(false);
jconfig.setExcludes(new String[] { "mainarea" });
JSONArray arr = JSONArray.fromObject(list, jconfig);//这一步报错
json.put("totalProperty", total);
json.put("root", arr);
try {
this.getResponse().getWriter().print(json);
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
2011-03-25 16:39:10:WARN http-8080-3 net.sf.json.JSONObject -Property 'handler' has no read method. SKIPPED
2011-03-25 16:39:10:WARN http-8080-3 net.sf.json.JSONObject -Property 'transactionTimeout' has no read method. SKIPPED
2011-03-25 16:39:12:ERROR http-8080-3 freeer.runtime -Method public java.lang.String org.apache.commons.lang.exception.NestableRuntimeException.getMessage(int) threw an exception when invoked on net.sf.json.JSONException: java.lang.NoSuchMethodException: Property 'delegate' has no getter method
The problematic instruction:
----------
==> ${msg[0]} [on line 68, column 29 in org/apache/struts2/dispatcher/error.ftl]
----------Java backtrace for programmers:
----------
freeer.template.TemplateModelException: Method public java.lang.String org.apache.commons.lang.exception.NestableRuntimeException.getMessage(int) threw an exception when invoked on net.sf.json.JSONException: java.lang.NoSuchMethodException: Property 'delegate' has no getter method
at freeer.ext.beans.SimpleMethodModel.exec(SimpleMethodModel.java:130)
at freeer.ext.beans.SimpleMethodModel.get(SimpleMethodModel.java:138)
at freeer.core.DynamicKeyName.dealWithNumericalKey(DynamicKeyName.java:111)
at freeer.core.DynamicKeyName._getAsTemplateModel(DynamicKeyName.java:90)
at freeer.core.Expression.getAsTemplateModel(Expression.java:89)
at freeer.core.Expression.getStringValue(Expression.java:93)
at freeer.core.DollarVariable.accept(DollarVariable.java:76)
at freeer.core.Environment.visit(Environment.java:209)
at freeer.core.MixedContent.accept(MixedContent.java:92)
at freeer.core.Environment.visit(Environment.java:209)
at freeer.core.IfBlock.accept(IfBlock.java:82)
at freeer.core.Environment.visit(Environment.java:209)
at freeer.core.IteratorBlock$Context.runLoop(IteratorBlock.java:179)
at freeer.core.Environment.visit(Environment.java:416)
at freeer.core.IteratorBlock.accept(IteratorBlock.java:102)
at freeer.core.Environment.visit(Environment.java:209)
at freeer.core.MixedContent.accept(MixedContent.java:92)
at freeer.core.Environment.visit(Environment.java:209)
at freeer.core.IfBlock.accept(IfBlock.java:82)
at freeer.core.Environment.visit(Environment.java:209)
at freeer.core.MixedContent.accept(MixedContent.java:92)
at freeer.core.Environment.visit(Environment.java:209)
at freeer.core.Environment.process(Environment.java:189)
at freeer.template.Template.process(Template.java:237)
at org.apache.struts2.dispatcher.Dispatcher.sendError(Dispatcher.java:748)
at org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:505)
at org.apache.struts2.dispatcher.ng.ExecuteOperations.executeAction(ExecuteOperations.java:77)
at org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.doFilter(StrutsPrepareAndExecuteFilter.java:91)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.springframework.orm.hibernate3.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:198)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:857)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.NullPointerException
at freeer.ext.beans.SimpleMemberModel.unwrapArguments(SimpleMemberModel.java:85)
at freeer.ext.beans.SimpleMethodModel.exec(SimpleMethodModel.java:106)
... 43 more
2011-3-25 16:39:12 org.apache.catalina.core.StandardWrapperValve invoke
严重: Servlet.service() for servlet default threw exception
java.lang.IllegalStateException
at org.apache.catalina.connector.ResponseFacade.sendError(ResponseFacade.java:407)
at org.apache.struts2.dispatcher.Dispatcher.sendError(Dispatcher.java:752)
at org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:505)
at org.apache.struts2.dispatcher.ng.ExecuteOperations.executeAction(ExecuteOperations.java:77)
at org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.doFilter(StrutsPrepareAndExecuteFilter.java:91)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.springframework.orm.hibernate3.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:198)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:857)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
at java.lang.Thread.run(Unknown Source)