Java Servlet Gson（）.toJson无限循环
我在servlet中遇到了一些问题，每次我更改下拉菜单中的选项， 一个不同的值将被传递给servlet，然后它将产生一个无限循环。当我没有更改下拉列表中的选项（值没有更改）时，没有错误 这是mycode： 我的Javascript：Java Servlet Gson（）.toJson无限循环,java,javascript,servlets,gson,Java,Javascript,Servlets,Gson,我在servlet中遇到了一些问题，每次我更改下拉菜单中的选项， 一个不同的值将被传递给servlet，然后它将产生一个无限循环。当我没有更改下拉列表中的选项（值没有更改）时，没有错误 这是mycode： 我的Javascript： <script> function loadStaff(){ //dropdown var positionDropDown = document.getElementById("positionsDropdown"); //value of the
<script>
function loadStaff(){
//dropdown
var positionDropDown = document.getElementById("positionsDropdown");
//value of the drop down
var positionID = positionDropDown.options[positionDropDown.selectedIndex].value;
$.getJSON('loadStaff?positionID=' + positionID, function(data) {
-- no populate code yet
});
}
</script>
> INFO: WebModule[null] ServletContext.log(): The server side
> component of the HTTP Monitor has detected a
> java.lang.StackOverflowError. This happens when there is an infinite
> loop in the web module. Correct the cause of the infinite loop before
> running the web module again.
>
> INFO: The server side component of the HTTP Monitor has detected a
> java.lang.StackOverflowError. This happens when there is an infinite
> loop in the web module. Correct the cause of the infinite loop before
> running the web module again. WARNING:
> StandardWrapperValve[AjaxServlet]: Servlet.service() for servlet
> AjaxServlet threw exception java.lang.StackOverflowError
> WARNING: StandardWrapperValve[AjaxServlet]: Servlet.service() for
> servlet AjaxServlet threw exception java.lang.StackOverflowError at
> sun.util.calendar.ZoneInfo.getOffsets(ZoneInfo.java:248) at
> java.util.GregorianCalendar.computeFields(GregorianCalendar.java:2276)
> at
> java.util.GregorianCalendar.computeFields(GregorianCalendar.java:2248)
> at java.util.Calendar.setTimeInMillis(Calendar.java:1140) at
> java.util.Calendar.setTime(Calendar.java:1106) at
> java.text.SimpleDateFormat.format(SimpleDateFormat.java:955) at
> java.text.SimpleDateFormat.format(SimpleDateFormat.java:948) at
> java.text.DateFormat.format(DateFormat.java:336) at
> com.google.gson.internal.bind.DateTypeAdapter.write(DateTypeAdapter.java:90)
> at
> com.google.gson.internal.bind.DateTypeAdapter.write(DateTypeAdapter.java:41)
> at
> com.google.gson.internal.bind.TypeAdapterRuntimeTypeWrapper.write(TypeAdapterRuntimeTypeWrapper.java:68)
> at
> com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$1.write(ReflectiveTypeAdapterFactory.java:89)
> at
> com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$Adapter.write(ReflectiveTypeAdapterFactory.java:195)
> at com.google.gson.Gson$FutureTypeAdapter.write(Gson.java:892) at
> com.google.gson.internal.bind.TypeAdapterRuntimeTypeWrapper.write(TypeAdapterRuntimeTypeWrapper.java:68)
> at
> com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$1.write(ReflectiveTypeAdapterFactory.java:89)
> at
> com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$Adapter.write(ReflectiveTypeAdapterFactory.java:195)
> at
> com.google.gson.internal.bind.TypeAdapterRuntimeTypeWrapper.write(TypeAdapterRuntimeTypeWrapper.java:68)
> at
> com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$1.write(ReflectiveTypeAdapterFactory.java:89)
> at
> com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$Adapter.write(ReflectiveTypeAdapterFactory.java:195)
> at com.google.gson.Gson$FutureTypeAdapter.write(Gson.java:892) at
> com.google.gson.internal.bind.TypeAdapterRuntimeTypeWrapper.write(TypeAdapterRuntimeTypeWrapper.java:68)
> at
> com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$1.write(ReflectiveTypeAdapterFactory.java:89)
> at
> com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$Adapter.write(ReflectiveTypeAdapterFactory.java:195)
> at
> com.google.gson.internal.bind.TypeAdapterRuntimeTypeWrapper.write(TypeAdapterRuntimeTypeWrapper.java:68)
> at
> com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$1.write(ReflectiveTypeAdapterFactory.java:89)
> at
> com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$Adapter.write(ReflectiveTypeAdapterFactory.java:195)
> at com.google.gson.Gson$FutureTypeAdapter.write(Gson.java:892)
@Entity
public class Staff implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Basic(optional = false)
@Column(name = "id")
private Integer id;
@Basic(optional = false)
@NotNull
@Size(min = 1, max = 45)
@Column(name = "last_name")
private String lastName;
@Basic(optional = false)
@NotNull
@Size(min = 1, max = 45)
@Column(name = "first_name")
private String firstName;
@Size(max = 45)
@Column(name = "middle_name")
private String middleName;
@Basic(optional = false)
@NotNull
@Size(min = 1, max = 6)
@Column(name = "gender")
private String gender;
@Basic(optional = false)
@NotNull
@Column(name = "date_of_birth")
@Temporal(TemporalType.DATE)
private Date dateOfBirth;
@Basic(optional = false)
@NotNull
@Size(min = 1, max = 45)
@Column(name = "nationality")
private String nationality;
@Basic(optional = false)
@NotNull
@Column(name = "date_hired")
@Temporal(TemporalType.TIMESTAMP)
private Date dateHired;
@Size(max = 20)
@Column(name = "status")
private String status;
@OneToMany(cascade = CascadeType.ALL, mappedBy = "staff")
private Collection<StaffApointments> staffApointmentsCollection;
@OneToOne(cascade = CascadeType.ALL, mappedBy = "staff")
private StaffContact staffContact;
@JoinColumn(name = "account_id", referencedColumnName = "id")
@ManyToOne(optional = false)
private Account accountId;
@JoinColumn(name = "position_id", referencedColumnName = "id")
@ManyToOne(optional = false)
private Position positionId;
public Staff() {
}
public Staff(Integer id) {
this.id = id;
}
public Staff(Integer id, String lastName, String firstName, String gender, Date dateOfBirth, String nationality, Date dateHired) {
this.id = id;
this.lastName = lastName;
this.firstName = firstName;
this.gender = gender;
this.dateOfBirth = dateOfBirth;
this.nationality = nationality;
this.dateHired = dateHired;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public String getMiddleName() {
return middleName;
}
public void setMiddleName(String middleName) {
this.middleName = middleName;
}
public String getGender() {
return gender;
}
public void setGender(String gender) {
this.gender = gender;
}
public Date getDateOfBirth() {
return dateOfBirth;
}
public void setDateOfBirth(Date dateOfBirth) {
this.dateOfBirth = dateOfBirth;
}
public String getNationality() {
return nationality;
}
public void setNationality(String nationality) {
this.nationality = nationality;
}
public Date getDateHired() {
return dateHired;
}
public void setDateHired(Date dateHired) {
this.dateHired = dateHired;
}
public String getStatus() {
return status;
}
public void setStatus(String status) {
this.status = status;
}
@XmlTransient
public Collection<StaffApointments> getStaffApointmentsCollection() {
return staffApointmentsCollection;
}
public void setStaffApointmentsCollection(Collection<StaffApointments> staffApointmentsCollection) {
this.staffApointmentsCollection = staffApointmentsCollection;
}
public StaffContact getStaffContact() {
return staffContact;
}
public void setStaffContact(StaffContact staffContact) {
this.staffContact = staffContact;
}
public Account getAccountId() {
return accountId;
}
public void setAccountId(Account accountId) {
this.accountId = accountId;
}
public Position getPositionId() {
return positionId;
}
public void setPositionId(Position positionId) {
this.positionId = positionId;
}
@Override
public int hashCode() {
int hash = 0;
hash += (id != null ? id.hashCode() : 0);
return hash;
}
@Override
public boolean equals(Object object) {
// TODO: Warning - this method won't work in the case the id fields are not set
if (!(object instanceof Staff)) {
return false;
}
Staff other = (Staff) object;
if ((this.id == null && other.id != null) || (this.id != null && !this.id.equals(other.id))) {
return false;
}
return true;
}
@Override
public String toString() {
return "entity.Staff[ id=" + id + " ]";
}
}
@实体
公共类Staff实现可序列化{
私有静态最终长serialVersionUID=1L；
@身份证
@GeneratedValue（策略=GenerationType.IDENTITY）
@基本（可选=假）
@列（name=“id”）
私有整数id；
@基本（可选=假）
@NotNull
@尺寸（最小值=1，最大值=45）
@列（name=“last_name”）
私有字符串lastName；
@基本（可选=假）
@NotNull
@尺寸（最小值=1，最大值=45）
@列（name=“first_name”）
私有字符串名；
@尺寸（最大值=45）
@列（name=“middle_name”）
私有字符串名称；
@基本（可选=假）
@NotNull
@尺寸（最小值=1，最大值=6）
@列（name=“gender”）
私人字符串性别；
@基本（可选=假）
@NotNull
@列（name=“出生日期”）
@时态（TemporalType.DATE）
私人出生日期；
@基本（可选=假）
@NotNull
@尺寸（最小值=1，最大值=45）
@列（name=“国籍”）
私人国籍；
@基本（可选=假）
@NotNull
@列（name=“雇用日期”）
@时态（TemporalType.TIMESTAMP）
私人约会；
@尺寸（最大值=20）
@列（name=“status”）
私有字符串状态；
@OneToMany（cascade=CascadeType.ALL，mappedBy=“staff”）
私人收款staffapointenscollection；
@OneTONE（cascade=CascadeType.ALL，mappedBy=“staff”）
私人员工联系人；员工联系人；
@JoinColumn（name=“account\u id”，referencedColumnName=“id”）
@多通（可选=假）
私人帐户账号；
@JoinColumn（name=“position\u id”，referencedColumnName=“id”）
@多通（可选=假）
私人职位ID；
公职人员（）{
}
公职人员（整数id）{
this.id=id；
}
公职人员（整数id、字符串姓氏、字符串姓氏、字符串性别、出生日期、字符串国籍、雇用日期）{
this.id=id；
this.lastName=lastName；
this.firstName=firstName；
这个。性别=性别；
this.dateOfBirth=出生日期；
国籍=国籍；
this.dateHired=dateHired；
}
公共整数getId（）{
返回id；
}
公共无效集合id（整数id）{
this.id=id；
}
公共字符串getLastName（）{
返回姓氏；
}
public void setLastName（字符串lastName）{
this.lastName=lastName；
}
公共字符串getFirstName（）{
返回名字；
}
public void setFirstName（字符串firstName）{
this.firstName=firstName；
}
公共字符串getMiddleName（）{
返回中间名；
}
public void setMiddleName（字符串middleName）{
this.middleName=middleName；
}
公共字符串getGender（）{
返回性别；
}
公共无效设置性别（字符串性别）{
这个。性别=性别；
}
公共日期getDateOfBirth（）{
出生返回日期；
}
公共无效设置出生日期（出生日期）{
this.dateOfBirth=出生日期；
}
公共字符串getNational（）{
返回国籍；
}
公共国籍（字符串国籍）{
国籍=国籍；
}
公共日期getDateHired（）{
返回日期；
}
公共作废setDateHired（雇用日期）{
this.dateHired=dateHired；
}
公共字符串getStatus（）{
返回状态；
}
公共无效设置状态（字符串状态）{
这个状态=状态；
}
@XmlTransient
公共集合GetStaffaPointsCollection（）{
返回StataPointsCollection；
}
公共作废SetStataPointsCollection（集合StataPointsCollection）{
this.staffApointmentsCollection=staffApointmentsCollection；
}
公共StaffContact getStaffContact（）{
返回员工联系人；
}
公共无效设置StaffContact（StaffContact StaffContact）{
this.staffContact=staffContact；
}
公共帐户getAccountId（）{
返回accountId；
}
公共无效setAccountId（帐户ID）{
this.accountId=accountId；
}
公共位置getPositionId（）{
返回位置ID；
}
公共无效setPositionId（职位职位ID）{
this.positionId=positionId；
}
@凌驾
公共int hashCode（）{
int hash=0；
hash+=（id！=null？id.hashCode（）：0）；
返回散列；
}
@凌驾
公共布尔等于（对象）{
//TODO:警告-如果未设置id字段，此方法将不起作用
if（！（人员的对象实例））{
返回false；
}
Staff other=（Staff）对象；
如果（（this.id==null&&other.id！=null）| |（this.id！=null&&！this.id.equals（other.id）））{
返回false；
}
返回true；
}
@凌驾
公共字符串toString（）{
返回“entity.Staff[id=“+id+”]”；
}
}
@Entity
public class Position implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Basic(optional = false)
@Column(name = "id")
private Integer id;
@Basic(optional = false)
@NotNull
@Size(min = 1, max = 45)
@Column(name = "name")
private String name;
@OneToMany(cascade = CascadeType.ALL, mappedBy = "positionId")
private Collection<Staff> staffCollection;
public Position() {
}
public Position(Integer id) {
this.id = id;
}
public Position(Integer id, String name) {
this.id = id;
this.name = name;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
@XmlTransient
public Collection<Staff> getStaffCollection() {
return staffCollection;
}
public void setStaffCollection(Collection<Staff> staffCollection) {
this.staffCollection = staffCollection;
}
@Override
public int hashCode() {
int hash = 0;
hash += (id != null ? id.hashCode() : 0);
return hash;
}
@Override
public boolean equals(Object object) {
// TODO: Warning - this method won't work in the case the id fields are not set
if (!(object instanceof Position)) {
return false;
}
Position other = (Position) object;
if ((this.id == null && other.id != null) || (this.id != null && !this.id.equals(other.id))) {
return false;
}
return true;
}
@Override
public String toString() {
return "entity.Position[ id=" + id + " ]";
}
}
@实体
公共类位置实现可序列化{
私有静态最终长serialVersionUID=1L；
@身份证
@GeneratedValue（策略=GenerationType.IDENTITY）
@基本（可选=假）
@列（name=“id”）
私有整数id；
@基本（可选=假）
@NotNull
@尺寸（最小值=1，最大值=45）
@列（name=“name”）
私有字符串名称；
@OneToMany（cascade=CascadeType.ALL，mappedBy=“posi
@Entity
public class Staff implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Basic(optional = false)
@Column(name = "id")
private Integer id;
@Basic(optional = false)
@NotNull
@Size(min = 1, max = 45)
@Column(name = "last_name")
private String lastName;
@Basic(optional = false)
@NotNull
@Size(min = 1, max = 45)
@Column(name = "first_name")
private String firstName;
@Size(max = 45)
@Column(name = "middle_name")
private String middleName;
@Basic(optional = false)
@NotNull
@Size(min = 1, max = 6)
@Column(name = "gender")
private String gender;
@Basic(optional = false)
@NotNull
@Column(name = "date_of_birth")
@Temporal(TemporalType.DATE)
private Date dateOfBirth;
@Basic(optional = false)
@NotNull
@Size(min = 1, max = 45)
@Column(name = "nationality")
private String nationality;
@Basic(optional = false)
@NotNull
@Column(name = "date_hired")
@Temporal(TemporalType.TIMESTAMP)
private Date dateHired;
@Size(max = 20)
@Column(name = "status")
private String status;
@OneToMany(cascade = CascadeType.ALL, mappedBy = "staff")
private Collection<StaffApointments> staffApointmentsCollection;
@OneToOne(cascade = CascadeType.ALL, mappedBy = "staff")
private StaffContact staffContact;
@JoinColumn(name = "account_id", referencedColumnName = "id")
@ManyToOne(optional = false)
private Account accountId;
@JoinColumn(name = "position_id", referencedColumnName = "id")
@ManyToOne(optional = false)
private Position positionId;
public Staff() {
}
public Staff(Integer id) {
this.id = id;
}
public Staff(Integer id, String lastName, String firstName, String gender, Date dateOfBirth, String nationality, Date dateHired) {
this.id = id;
this.lastName = lastName;
this.firstName = firstName;
this.gender = gender;
this.dateOfBirth = dateOfBirth;
this.nationality = nationality;
this.dateHired = dateHired;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public String getMiddleName() {
return middleName;
}
public void setMiddleName(String middleName) {
this.middleName = middleName;
}
public String getGender() {
return gender;
}
public void setGender(String gender) {
this.gender = gender;
}
public Date getDateOfBirth() {
return dateOfBirth;
}
public void setDateOfBirth(Date dateOfBirth) {
this.dateOfBirth = dateOfBirth;
}
public String getNationality() {
return nationality;
}
public void setNationality(String nationality) {
this.nationality = nationality;
}
public Date getDateHired() {
return dateHired;
}
public void setDateHired(Date dateHired) {
this.dateHired = dateHired;
}
public String getStatus() {
return status;
}
public void setStatus(String status) {
this.status = status;
}
@XmlTransient
public Collection<StaffApointments> getStaffApointmentsCollection() {
return staffApointmentsCollection;
}
public void setStaffApointmentsCollection(Collection<StaffApointments> staffApointmentsCollection) {
this.staffApointmentsCollection = staffApointmentsCollection;
}
public StaffContact getStaffContact() {
return staffContact;
}
public void setStaffContact(StaffContact staffContact) {
this.staffContact = staffContact;
}
public Account getAccountId() {
return accountId;
}
public void setAccountId(Account accountId) {
this.accountId = accountId;
}
public Position getPositionId() {
return positionId;
}
public void setPositionId(Position positionId) {
this.positionId = positionId;
}
@Override
public int hashCode() {
int hash = 0;
hash += (id != null ? id.hashCode() : 0);
return hash;
}
@Override
public boolean equals(Object object) {
// TODO: Warning - this method won't work in the case the id fields are not set
if (!(object instanceof Staff)) {
return false;
}
Staff other = (Staff) object;
if ((this.id == null && other.id != null) || (this.id != null && !this.id.equals(other.id))) {
return false;
}
return true;
}
@Override
public String toString() {
return "entity.Staff[ id=" + id + " ]";
}
}
@Entity
public class Position implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Basic(optional = false)
@Column(name = "id")
private Integer id;
@Basic(optional = false)
@NotNull
@Size(min = 1, max = 45)
@Column(name = "name")
private String name;
@OneToMany(cascade = CascadeType.ALL, mappedBy = "positionId")
private Collection<Staff> staffCollection;
public Position() {
}
public Position(Integer id) {
this.id = id;
}
public Position(Integer id, String name) {
this.id = id;
this.name = name;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
@XmlTransient
public Collection<Staff> getStaffCollection() {
return staffCollection;
}
public void setStaffCollection(Collection<Staff> staffCollection) {
this.staffCollection = staffCollection;
}
@Override
public int hashCode() {
int hash = 0;
hash += (id != null ? id.hashCode() : 0);
return hash;
}
@Override
public boolean equals(Object object) {
// TODO: Warning - this method won't work in the case the id fields are not set
if (!(object instanceof Position)) {
return false;
}
Position other = (Position) object;
if ((this.id == null && other.id != null) || (this.id != null && !this.id.equals(other.id))) {
return false;
}
return true;
}
@Override
public String toString() {
return "entity.Position[ id=" + id + " ]";
}
}