extjs +String2 +Spring 下的分页 以及返回json格式错误的问题

时间:2024-01-13 17:01:14

首先,分页  很简单.

1前台extjs数据源,

var shipMgrStore = Ext.create('Ext.data.Store', {
model: 'App.ShipMgr.model.ShipModel',
autoLoad: true,
pageSize: 15,
// timeout: 300000,
// simpleSortMode:true,
proxy: {
type: 'ajax',
url:'<%=request.getContextPath()%>/getDuncanJiang.action',
reader: {
reader: 'json',
root: 'sfdcConfigList',
totalProperty: 'totalProperty'
},
},
});

其他的属性就不说了.

主要是两个参数:一个是   root  :表示接收到的数据从这个   sfdcConfigLIst  开始解析

                 一个是 totalProperty   :表示返回数据的总行数

2 grid

var shipMgrGrid = Ext.create('Ext.grid.Panel', {
store: shipMgrStore,
columnLines: true,
rowLines: true,
region: 'center',
autoScroll: true,
forceFit: true,
loadMask: true,
border: true,
renderTo:'showPanel',
bbar: Ext.create('Ext.toolbar.Paging', {
id:'<portlet:namespace />bbar',
store: shipMgrStore,
pageSize:15,
displayInfo: true
}),
columns: [
Ext.create('Ext.grid.RowNumberer', {
text: 'numbr',
width: 50
}), {
text: 'id',
dataIndex: 'id'
}
, {
text: 'plant',
dataIndex: 'plant'
}, {
text: 'deviceId',
dataIndex: 'deviceId'
}, {
text: 'sfdcPort',
dataIndex: 'sfdcPort'
}, {
text: 'description',
dataIndex: 'description'
}
],
bbar: Ext.create('Ext.toolbar.Paging', {
id: '<portlet:namespace />duncanjiangbbar',
pageSize: 15,
store: shipMgrStore,
displayInfo: true,
displayMsg: '<%= bundle.getString("message.records") %> {0} - {1} of {2}',
emptyMsg: '<%= bundle.getString("page.nodata") %>'
})
});

传递二个参数 limit : 每页显示多少条 (pageSize)

       start :从第几条数据开始 (自动传递)

  当你在前台点击下一页的时候,它就会自动把 limit 和 start 传到后台查询数据,然后返回对面页的数据过来

后台的话 


private int start;
  //get  set
   private int limit;

  //get set

public String findSfdcByDeviceId(){
try {
int limit=this.limit;
int start=this.start;
    // 根据传过来的参数,查询数据
  this.fileNameList=testService.getSfdcCOnfigObjbyDeviceId(type,start,limit);
   //总条数
totalProperty=testService.getSfdcCOunt(type); }

其实就是 返回 两个数据集,一个是  fileNameList,当页数据, totalPropery是总共有多少条数据.

 定义属性接收前台传过来的 limit,start,并且生成get,set方法

&&&&&&&&&&&&&&&我是傲娇的分割线&&&&&&&&&&&&&&&&&&&&&&&

 然后做这个分页的时候还遇上一个问题,返回的 JSON数据到前台的时候报了一个错

html><head><title>Apache Tomcat/7.0.39 - Error report</title><style><!--H1 {font-family:Tahoma,Arial,sans-serif;color:white;background-color:#525D76;font-size:22px;} H2 {font-family:Tahoma,Arial,sans-serif;color:white;background-color:#525D76;font-size:16px;} H3 {font-family:Tahoma,Arial,sans-serif;color:white;background-color:#525D76;font-size:14px;} BODY {font-family:Tahoma,Arial,sans-serif;color:black;background-color:white;} B {font-family:Tahoma,Arial,sans-serif;color:white;background-color:#525D76;} P {font-family:Tahoma,Arial,sans-serif;background:white;color:black;font-size:12px;}A {color : black;}A.name {color : black;}HR {color : #525D76;}--></style> </head><body><h1>HTTP Status 500 - org.apache.struts2.json.JSONException: org.apache.struts2.json.JSONException: org.apache.struts2.json.JSONException: org.apache.struts2.json.JSONException: org.apache.struts2.json.JSONException: java.lang.IllegalAccessException: Class org.apache.struts2.json.JSONWriter can not access a member of class org.apache.commons.dbcp.PoolingDataSource$PoolGuardConnectionWrapper with modifiers &quot;public&quot;</h1><HR size="1" noshade="noshade"><p><b>type</b> Exception report</p><p><b>message</b> <u>org.apache.struts2.json.JSONException: org.apache.struts2.json.JSONException: org.apache.struts2.json.JSONException: org.apache.struts2.json.JSONException: org.apache.struts2.json.JSONException: java.lang.IllegalAccessException: Class org.apache.struts2.json.JSONWriter can not access a member of class org.apache.commons.dbcp.PoolingDataSource$PoolGuardConnectionWrapper with modifiers &quot;public&quot;</u></p><p><b>description</b> <u>The server encountered an internal error that prevented it from fulfilling this request.</u></p><p><b>exception</b> <pre>org.apache.struts2.json.JSONException: org.apache.struts2.json.JSONException: org.apache.struts2.json.JSONException: org.apache.struts2.json.JSONException: org.apache.struts2.json.JSONException: org.apache.struts2.json.JSONException: java.lang.IllegalAccessException: Class org.apache.struts2.json.JSONWriter can not access a member of class org.apache.commons.dbcp.PoolingDataSource$PoolGuardConnectionWrapper with modifiers &quot;public&quot;
org.apache.struts2.json.JSONWriter.bean(JSONWriter.java:243)
org.apache.struts2.json.JSONWriter.process(JSONWriter.java:165)
org.apache.struts2.json.JSONWriter.value(JSONWriter.java:131)
org.apache.struts2.json.JSONWriter.write(JSONWriter.java:99)
org.apache.struts2.json.JSONUtil.serialize(JSONUtil.java:112)
org.apache.struts2.json.JSONResult.execute(JSONResult.java:198)
com.opensymphony.xwork2.DefaultActionInvocation.executeResult(DefaultActionInvocation.java:362)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:266)
com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:165)
com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
com.opensymphony.xwork2.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:252)
org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor.doIntercept(AnnotationValidationInterceptor.java:68)
com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept(ConversionErrorInterceptor.java:122)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:195)
com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:195)
com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept(StaticParametersInterceptor.java:179)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
org.apache.struts2.interceptor.MultiselectInterceptor.intercept(MultiselectInterceptor.java:75)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
org.apache.struts2.interceptor.CheckboxInterceptor.intercept(CheckboxInterceptor.java:94)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:235)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)

这个是由于后台返回前台的数据中,会包含所有的get开头的,包括你的get属性,get开头的方法等等等等.导致的问题.

解决 : 1.在这些不需要返回的get方法的前面加上@JSON(serialize=false)这个注解.

     2.把查询返回的数据集做一个简单的处理,通过gson进行解析.具体为什么要这样....我也不清楚..... 哈哈哈哈,反正这样就可以了

public String findSfdcByDeviceId(){
try {
int limit=this.limit;
int start=this.start;
this.fileNameList=testService.getSfdcCOnfigObjbyDeviceId(type,start,limit);
Gson gson=new Gson();
List<SfdcConfigObj> rs=new ArrayList<SfdcConfigObj>();
String str=JSONArray.fromObject(fileNameList).toString();
Type ortype = new TypeToken<ArrayList<SfdcConfigObj>>() {}.getType();
rs=gson.fromJson(str, ortype);
for(SfdcConfigObj sfdc : rs){
sfdcConfigList.add(sfdc);
} totalProperty=testService.getSfdcCOunt(type); } catch (Exception e) {
e.printStackTrace();
} return Action.SUCCESS;
}

注意!!!   如果你要返回的,比如一个属性,暂且叫他为   number.这时候他的get方法如果你也加了这个注解的话,那么前台是获取不到这个值的.