struts2 Ajax验证用户名是出现异常,望各位帮帮忙!谢谢

type Exception report

message

description The server encountered an internal error () that prevented it from fulfilling this request.

exception

com.googlecode.jsonplugin.JSONException: com.googlecode.jsonplugin.JSONException: com.googlecode.jsonplugin.JSONException: com.googlecode.jsonplugin.JSONException: com.googlecode.jsonplugin.JSONException: com.googlecode.jsonplugin.JSONException: com.googlecode.jsonplugin.JSONException: com.googlecode.jsonplugin.JSONException: com.googlecode.jsonplugin.JSONException: com.googlecode.jsonplugin.JSONException: java.lang.IllegalAccessException: Class com.googlecode.jsonplugin.JSONWriter can not access a member of class org.apache.commons.dbcp.PoolingDataSource$PoolGuardConnectionWrapper with modifiers "public"
com.googlecode.jsonplugin.JSONWriter.bean(JSONWriter.java:239)
com.googlecode.jsonplugin.JSONWriter.process(JSONWriter.java:161)
com.googlecode.jsonplugin.JSONWriter.value(JSONWriter.java:127)
com.googlecode.jsonplugin.JSONWriter.write(JSONWriter.java:95)
com.googlecode.jsonplugin.JSONUtil.serialize(JSONUtil.java:98)
com.googlecode.jsonplugin.JSONResult.execute(JSONResult.java:179)
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)
com.opensymphony.xwork2.interceptor.ModelDrivenInterceptor.intercept(ModelDrivenInterceptor.java:89)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
com.opensymphony.xwork2.interceptor.ScopedModelDrivenInterceptor.intercept(ScopedModelDrivenInterceptor.java:130)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
org.apache.struts2.interceptor.debugging.DebuggingInterceptor.intercept(DebuggingInterceptor.java:267)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
com.opensymphony.xwork2.interceptor.ChainingInterceptor.intercept(ChainingInterceptor.java:126)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
com.opensymphony.xwork2.interceptor.PrepareInterceptor.doIntercept(PrepareInterceptor.java:138)
com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
com.opensymphony.xwork2.interceptor.I18nInterceptor.intercept(I18nInterceptor.java:165)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
org.apache.struts2.interceptor.ServletConfigInterceptor.intercept(ServletConfigInterceptor.java:164)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
com.opensymphony.xwork2.interceptor.AliasInterceptor.intercept(AliasInterceptor.java:179)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:176)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
org.apache.struts2.impl.StrutsActionProxy.execute(StrutsActionProxy.java:52)
org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:488)
org.apache.struts2.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:395)
================下面是我的action==================
package action;

import java.util.List;

import service.StudentService;
import bean.PageBean;
import bean.Student;

import com.opensymphony.xwork2.ActionSupport;

public class StudentAction extends ActionSupport {
/**
*
*/
private static final long serialVersionUID = -8773185263698583153L;
private StudentService studentService;
private List<Student> student;
private int page = 1;
private PageBean pageBean;
private Long id[];
private String queryname;
private Student findStudent;
private Long id2;
private String username;
private String password;

public Long getId2() {
return id2;
}

public void setId2(Long id2) {
this.id2 = id2;
}

public String getPassword() {
return password;
}

public void setPassword(String password) {
this.password = password;
}

public String getUsername() {
return username;
}

public void setUsername(String username) {
this.username = username;
}

public Student getFindStudent() {
return findStudent;
}

public void setFindStudent(Student findStudent) {
this.findStudent = findStudent;
}

public String getQueryname() {
return queryname;
}

public void setQueryname(String queryname) {
this.queryname = queryname;
}

public Long[] getId() {
return id;
}

public void setId(Long[] id) {
this.id = id;
}

public PageBean getPageBean() {
return pageBean;
}

public void setPageBean(PageBean pageBean) {
this.pageBean = pageBean;
}

public int getPage() {
return page;
}

public void setPage(int page) {
this.page = page;
}

public StudentService getStudentService() {
return studentService;
}

public void setStudentService(StudentService studentService) {
this.studentService = studentService;
}

public List<Student> getStudent() {
return student;
}

public void setStudent(List<Student> student) {
this.student = student;
}

public String listAll() throws Exception {
this.pageBean = studentService.queryForPage(10, page,this.getQueryname());
return SUCCESS;
}

public String deletes() throws Exception {
int i = studentService.deletes(id);
if(i>0)
return SUCCESS;
else
return INPUT;
}

public String update() throws Exception {
this.setFindStudent(studentService.getById(id[0]));
return SUCCESS;
}

public String doupdate() throws Exception {
Student student1 = new Student();
student1.setId(this.getId2());
student1.setName(this.getUsername());
student1.setPwd(this.getPassword());
studentService.attachDirty(student1);
return SUCCESS;
}
}
我在网上找了下有的说getter方法有关，但我还是不太清楚。谢谢各位!