在struts2 in action中所见，这样封装后省去了大部分crud反复代码。尽管还不能理悟。先记下来。
abstract class BaseAction extends ActionSupport {
protected DB db;
protected static Log log = LogFactory.getLog(BaseAction.class);
private long requestId;
private boolean readOnly = false;
private String mappedRequest;
@SkipValidation
public String show(){
setReadOnly(true);
setMappedRequest(Constants.LIST);
return SUCCESS;
}
@SkipValidation
public String add(){
setMappedRequest(Constants.SAVE);
return SUCCESS;
}
public String save(){
db.save(getModel());
return list();
}
@SkipValidation
public String edit(){
setMappingRequest(Constants.UPDATE);
return SUCCESS;
}
public String update(){
db.save(getModel());
return list();
}
@SkipValidation
public String destroy(){
setReadOnly(true);
setMappingRequest(Constants.REMOVE);
return Constants.SUCCESS;
}
public String remove(){
db.remove(getModel());
return list();
}
@SkipValidation
public String list(){
setMappingedRequest(Constants.LIST);
return Constants.LIST;
}
public String getActionClass(){
return getClass().getSimpleName();
}
public String getDestination(){
return getClass().getSimpleName();
}
public String getActionMethod(){
return mappedRequest;
}
public void setActionMethod(String method){
this.mappedRequest = method;
}
public void setMappedRequest(String actionMethed){
this.mappedRequest = getActionClass() + "_" + actionMethed;
log.debug("setting mappedRequest to "+ getActionClass() + "_" + actionMethed);
}
public void setReadOnly(boolean readOnly){
this.readOnly = readOnly;
log.debug("setting readOnly to "+readOnly);
}
public long getRequestId(){
return requestId;
}
public void setRequestId(long requestId){
this.requestId = requestId;
}
public void setDb(DB db){
this.db = db;
}
public boolean isReadOnly(){
return readOnly;
}
public abstract Object getModel();
}public class MemberAction extends BaseAction implements ModelDriven,Preparable {
private Member model;
public Member getModel(){
return model;
}
public void prepare() throws Exception{
if(getRequestId() == 0){
model = new Member();
}else{
model = (Member) db.get(getRequestId);
}
}
}