PrintWriter printWriter;
try {
printWriter = getResponse().getWriter();
printWriter.write(JSONArray.fromObject(dutyList).toString());
printWriter.close();
} catch (IOException e) {
// TODO Auto-generated catch block
}以上代码是让dutyList中的数据转换成JSON数据格式用于前台JS，其中有Date数据类型无法转换。出现错误，以下是控制台错误信息，可能我描述的问题不够清楚，是因为本人技术有限，希望了解的人帮忙解答，谢谢。
2012-03-07 17:18:47,958 ERROR [DutyListInitOrSelectAction] net.sf.json.JSONException: java.lang.reflect.InvocationTargetException at net.sf.json.JSONObject._fromBean(JSONObject.java:738) at net.sf.json.JSONObject.fromObject(JSONObject.java:182) at net.sf.json.JSONObject._processValue(JSONObject.java:2426) at net.sf.json.JSONObject._setInternal(JSONObject.java:2447) at net.sf.json.JSONObject.setValue(JSONObject.java:1189) at net.sf.json.JSONObject._fromBean(JSONObject.java:725) at net.sf.json.JSONObject.fromObject(JSONObject.java:182) at net.sf.json.JSONArray._processValue(JSONArray.java:2294) at net.sf.json.JSONArray.processValue(JSONArray.java:2325) at net.sf.json.JSONArray.addValue(JSONArray.java:2312) at net.sf.json.JSONArray._fromCollection(JSONArray.java:841) at net.sf.json.JSONArray.fromObject(JSONArray.java:137) at net.sf.json.JSONArray.fromObject(JSONArray.java:120) at com.gage.oa.personaloffice.duty.action.DutyListInitOrSelectAction.executeBussiness(DutyListInitOrSelectAction.java:154) at com.gage.fw.web.action.BaseGageAction.execute(BaseGageAction.java:225) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) at com.opensymphony.xwork2.DefaultActionInvocation.invokeAction(DefaultActionInvocation.java:452) at com.opensymphony.xwork2.DefaultActionInvocation.invokeActionOnly(DefaultActionInvocation.java:291) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:254) at com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:176) at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) at com.opensymphony.xwork2.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:263) at org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor.doIntercept(AnnotationValidationInterceptor.java:68) at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) at com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept(ConversionErrorInterceptor.java:138) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:207) at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:207) at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) at com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept(StaticParametersInterceptor.java:190) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) at org.apache.struts2.interceptor.MultiselectInterceptor.intercept(MultiselectInterceptor.java:75) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) at org.apache.struts2.interceptor.CheckboxInterceptor.intercept(CheckboxInterceptor.java:94) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) at org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:243) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) at com.opensymphony.xwork2.interceptor.ModelDrivenInterceptor.intercept(ModelDrivenInterceptor.java:100) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) at com.opensymphony.xwork2.interceptor.ScopedModelDrivenInterceptor.intercept(ScopedModelDrivenInterceptor.java:141) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) at org.apache.struts2.interceptor.debugging.DebuggingInterceptor.intercept(DebuggingInterceptor.java:270) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) at com.opensymphony.xwork2.interceptor.ChainingInterceptor.intercept(ChainingInterceptor.java:145) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) at com.opensymphony.xwork2.interceptor.PrepareInterceptor.doIntercept(PrepareInterceptor.java:171) at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) at com.opensymphony.xwork2.interceptor.I18nInterceptor.intercept(I18nInterceptor.java:176) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) at org.apache.struts2.interceptor.ServletConfigInterceptor.intercept(ServletConfigInterceptor.java:164) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) at com.opensymphony.xwork2.interceptor.AliasInterceptor.intercept(AliasInterceptor.java:190) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) at com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:187) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) at com.gage.fw.aop.AuthLoginInterceptor.intercept(AuthLoginInterceptor.java:64) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) at org.apache.struts2.impl.StrutsActionProxy.execute(StrutsActionProxy.java:52) at org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:498) 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.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88) 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:291) at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:859) at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:602) at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489) at java.lang.Thread.run(Unknown Source) Caused by: java.lang.reflect.InvocationTargetException at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) at org.apache.commons.beanutils.PropertyUtilsBean.invokeMethod(PropertyUtilsBean.java:1773) at org.apache.commons.beanutils.PropertyUtilsBean.getSimpleProperty(PropertyUtilsBean.java:1132) at org.apache.commons.beanutils.PropertyUtilsBean.getNestedProperty(PropertyUtilsBean.java:686) at org.apache.commons.beanutils.PropertyUtilsBean.getProperty(PropertyUtilsBean.java:715) at org.apache.commons.beanutils.PropertyUtils.getProperty(PropertyUtils.java:290) at net.sf.json.JSONObject._fromBean(JSONObject.java:713) ... 89 more Caused by: java.lang.IllegalArgumentException at java.sql.Time.getDate(Unknown Source) ... 99 more
不要用java.sql.Time，用java.util.Date
json-lib有一个配置类JsonConfig
通过JsonConfig可以注册一个字段处理器
实现JsonValueProcessor接口即可
JsonConfig jsonConfig = new JsonConfig();
jsonConfig.registerJsonValueProcessor(java.util.Date.class,new JsonValueProcessor() {
private SimpleDateFormat sd = new SimpleDateFormat("yyyy-MM-dd");
public Object processObjectValue(String key, Object value, JsonConfig jsonConfig) {
return value == null ?"" : sd.format(value);
}
public Object processArrayValue(Object value, JsonConfig jsonConfig) {
return null;
}
});所以你最后应该把JsonConfig对象传入json操作方法
printWriter.write(JSONArray.fromObject(dutyList,jsonConfig).toString());
这是JDK的源码
public int getDate() {
throw new java.lang.IllegalArgumentException();
}
java.sql.Time.getDate：This method is deprecated and should not be used because SQL <code>TIME</code> values do not have a date component.
建议使用gson库来替代json-lib,gson提供更好自定义类型支持