Java 如何解决这个案件;“没有可实例化的子类型”;
这是我提供的类代码,当我编译这部分代码时,我得到了一个错误。。请帮帮我。Thx-u-guyJava 如何解决这个案件;“没有可实例化的子类型”;,java,eclipse,gwt,Java,Eclipse,Gwt,这是我提供的类代码,当我编译这部分代码时,我得到了一个错误。。请帮帮我。Thx-u-guy import java.io.Serializable; public class Offer implements Comparable<Object>, Serializable { private static final long serialVersionUID = 1L; private Product product; private Register
import java.io.Serializable;
public class Offer implements Comparable<Object>, Serializable {
private static final long serialVersionUID = 1L;
private Product product;
private RegisteredUser user;
private float amount;
//stati dell'offerta
private OfferState bestOffer;
private OfferState overtakenOffer;
private OfferState winnerOffer;
private OfferState loserOffer;
//stato attuale dell'offerta
private OfferState state;
public Offer(){}
public Offer(Product product, RegisteredUser user, float amount)
{
this.user = user;
this.amount = amount;
this.product = product;
bestOffer = new BestOffer(this);
overtakenOffer = new OvertakenOffer(this);
winnerOffer = new WinnerOffer(this);
loserOffer = new LoserOffer(this);
state = bestOffer;
}
public RegisteredUser getUser() {
return user;
}
public float getAmount() {
return amount;
}
public void setAmount(float amount) {
this.amount = amount;
}
@Override
public int compareTo(Object arg0) {
return Float.compare(amount, ((Offer) arg0).getAmount());
}
public OfferState getBestOffer() {
return bestOffer;
}
public OfferState getOvertakenOffer() {
return overtakenOffer;
}
public OfferState getWinnerOffer() {
return winnerOffer;
}
public OfferState getLoserOffer() {
return loserOffer;
}
public OfferState getState() {
return state;
}
public void setState(OfferState state) {
this.state = state;
}
public void reciveOffer()
{
try
{
state.reciveOffer();
}
catch (UnsupportedOperationException e) {
}
}
public void deadline()
{
try
{
state.deadline();
}
catch (UnsupportedOperationException e) {
}
}
public Product getProduct() {
return product;
}
}
import java.io.Serializable;
公共类提供实现了可比较的、可序列化的{
私有静态最终长serialVersionUID=1L;
私人产品;
私人注册用户;
私人浮动金额;
//德尔奥弗塔车站
私人报价州最佳报价;
私人要约人;国家超越要约人;
私人报价人州winnerOffer;
私人发盘州输家;
//德尔奥弗塔酒店
私人要约人国家;
公开发售({}
公开发售(产品、注册用户、浮动金额)
{
this.user=用户;
这个。金额=金额;
本产品=产品;
最佳报价=新的最佳报价(本);
超车者=新超车者(本);
winnerOffer=新winnerOffer(本);
Loserofer=新的Loserofer(本);
状态=最佳报价;
}
公共注册服务器getUser(){
返回用户;
}
公共浮动金额(){
退货金额;
}
公开作废设置金额(浮动金额){
这个。金额=金额;
}
@凌驾
公共整数比较对象(对象arg0){
返回Float.compare(amount,((Offer)arg0.getAmount());
}
公开发售状态getBestOffer(){
返回最佳报价;
}
公开募股人州政府{
返回到noffer;
}
公开发售状态getWinnerOffer(){
返回winnerOffer;
}
公开发售状态getLoserOffer(){
返回loserOffer;
}
公开发售状态getState(){
返回状态;
}
公共无效设置状态(报价状态状态){
this.state=状态;
}
公开无效接收要约()
{
尝试
{
state.receiveoffer();
}
捕获(不支持操作异常e){
}
}
公众假期截止日期()
{
尝试
{
state.deadline();
}
捕获(不支持操作异常e){
}
}
公共产品{
退货产品;
}
}
所有成员,如Product、RegisteredUser、OfferState,也必须可序列化或标记为transient。我想它们不是你必须做的。这里有一个很好的例子:
该类是否位于“共享”文件夹中,供客户端和服务器包使用?