struts的No getter method问题

我在做下拉列表动态绑定是发生了No getter Method的错误，在form中，不是大小写的问题，上网查了一些资料，出的问题也和我不一样，急救啊！！！
jsp中代码如下：
<html:select property="choose">
<html:option value="0">------请选择------</html:option>
<html:optionsCollection name="bugRoleList" label="userRoleName" value="userRoleId" />
</html:select>
form中代码如下：
public class MissionForm extends ActionForm {
/**
*
*/
private static final long serialVersionUID = 1L;

/*
* Generated Methods
*/
private String misUserChoose;

private String choose;

private String misRoleChoose;

private String rwId;

private XtYh xtYh;

private String dyName;

private DyJq dyJq;

private RwSp rwSp;

private Integer rwState;

private Date rwDate = new Date();

private Set xtQxes = new HashSet(0);

public DyJq getDyJq() {
return dyJq;
}

public void setDyJq(DyJq dyJq) {
this.dyJq = dyJq;
}

public Date getRwDate() {
return rwDate;
}

public void setRwDate(Date rwDate) {
this.rwDate = rwDate;
}

public String getRwId() {
return rwId;
}

public void setRwId(String rwId) {
this.rwId = rwId;
}

public RwSp getRwSp() {
return rwSp;
}

public void setRwSp(RwSp rwSp) {
this.rwSp = rwSp;
}

public Integer getRwState() {
return rwState;
}

public void setRwState(Integer rwState) {
this.rwState = rwState;
}

public Set getXtQxes() {
return xtQxes;
}

public void setXtQxes(Set xtQxes) {
this.xtQxes = xtQxes;
}

public XtYh getXtYh() {
return xtYh;
}

public void setXtYh(XtYh xtYh) {
this.xtYh = xtYh;
}

/**
* Method validate
* @param mapping
* @param request
* @return ActionErrors
*/
public ActionErrors validate(ActionMapping mapping,
HttpServletRequest request) {
// TODO Auto-generated method stub
return null;
}

/**
* Method reset
* @param mapping
* @param request
*/
public void reset(ActionMapping mapping, HttpServletRequest request) {
// TODO Auto-generated method stub
}

public String getDyName() {
return dyName;
}

public void setDyName(String dyName) {
this.dyName = dyName;
}

public String getMisRoleChoose() {
return misRoleChoose;
}

public void setMisRoleChoose(String misRoleChoose) {
this.misRoleChoose = misRoleChoose;
}

public String getMisUserChoose() {
return misUserChoose;
}

public void setMisUserChoose(String misUserChoose) {
this.misUserChoose = misUserChoose;
}

public String getChoose() {
return this.choose;
}

public void setChoose(String choose) {
this.choose = choose;
}
}
其中，get和set方法都是自动生成的，大小写都符合要求，查询出的list没有问题,我试过了，如果不用form中的choose属性，换用form中的dyName属性，就没有问题了，郁闷中，为什么同一个form中的属性使用另外一个就可以了呢？急救啊！！！！