Passing Optional Parameter Via Extended Class Constructor

Following is a snippet of code I copied and have a question about when extending DataGridColumn class to sort numeric for colums that have numeric values:
CustomAdvancedDataGridColumn(columnName:String=null,numeric:Object=null)
super(columnName);
initCompare(numeric);
function initCompare(numeric:Object):void
if (numeric == NUMERIC) {
sortCompareFunction = numericCompare;
The extended class is supposed to receive variable "numeric" type Object in the constructor which is then supposed to be used in the initCompare function to determine if a column contains numeric values. This code didn't work for me as numeric variable remains null. To get it working I added a new public static const and private propery "numeric" and obtained it with get() set() to see if should the column should sort numeric. This works but you have to set the property in the extended datagrid column FLEX tag.
My question is how is the variable numeric in the code snippet above supposed to get it's new data for the initCompare function? I can't get it to be anything other than null.
Thanks for any insights...I'm new to FLEX.
Jason

Still searching for a solution.
Please note, that I'm using the syntax described in
<a href="http://help.sap.com/businessobject/product_guides/boexir31/en/xi3-1_url_reporting_opendocument_en.pdf">http://help.sap.com/businessobject/product_guides/boexir31/en/xi3-1_url_reporting_opendocument_en.pdf</a>
on page 65.
So did I get anything wrong? Help would be really appreciated, also Workarounds if there's no solution for the problem.

Similar Messages

Passing a parameter from one class to another class in the same package

Hi.
I am trying to pass a parameter from one class to another class with in a package.And i am Getting the variable as null every time.In the code there is two classes.
i. BugWatcherAction.java
ii.BugWatcherRefreshAction.Java.
We have implemented caching in the front-end level.But according to the business logic we need to clear the cache and again have to access the database after some actions are happened.There are another class file called BugwatcherPortletContent.java.
So, we are dealing with three java files.The database interaction is taken care by the portletContent.java file.Below I am giving the code for the perticular function in the bugwatcherPortletContent.java:
==============================================================
public Object loadContent() throws Exception {
Hashtable htStore = new Hashtable();
JetspeedRunData rundata = this.getInputData();
String pId = this.getPorletId();
PortalLogger.logDebug(" in the portlet content: "+pId);
pId1=pId;//done by sraha
htStore.put("PortletId", pId);
htStore.put("BW_HOME_URL",CommonUtil.getMessage("BW.Home.Url"));
htStore.put("BW_BUGVIEW_URL",CommonUtil.getMessage("BW.BugView.Url"));
HttpServletRequest request = rundata.getRequest();
PortalLogger.logDebug(
"BugWatcherPortletContent:: build normal context");
HttpSession session = null;
int bugProfileId = 0;
Hashtable bugProfiles = null;
Hashtable bugData = null;
boolean fetchProfiles = false;
try {
session = request.getSession(true);
// Attempting to get the profiles from the session.
//If the profiles are not present in the session, then they would have to be
// obtained from the database.
bugProfiles = (Hashtable) session.getAttribute("Profiles");
//Getting the selected bug profile id.
String bugProfileIdObj = request.getParameter("bugProfile" + pId);
// Getting the logged in user
String userId = request.getRemoteUser();
if (bugProfiles == null) {
fetchProfiles = true;
if (bugProfileIdObj == null) {
// setting the bugprofile id as -1 indicates "all profiles" is selected
bugProfileIdObj =(String) session.getAttribute("bugProfileId" + pId);
if (bugProfileIdObj == null) {
bugProfileId = -1;
else {
bugProfileId = Integer.parseInt(bugProfileIdObj);
else {
bugProfileId = Integer.parseInt(bugProfileIdObj);
session.setAttribute(
("bugProfileId" + pId),
Integer.toString(bugProfileId));
//fetching the bug list
bugData =BugWatcherAPI.getbugList(userId, bugProfileId, fetchProfiles);
PortalLogger.logDebug("BugWatcherPortletContent:: got bug data");
if (bugData != null) {
Hashtable htProfiles = (Hashtable) bugData.get("Profiles");
} else {
htStore.put("NoProfiles", "Y");
} catch (CodedPortalException e) {
htStore.put("Error", CommonUtil.getErrMessage(e.getMessage()));
PortalLogger.logException
("BugWatcherPortletContent:: CodedPortalException!!",e);
} catch (Exception e) {
PortalLogger.logException(
"BugWatcherPortletContent::Generic Exception!!",e);
htStore.put(     "Error",CommonUtil.getErrMessage(ErrorConstantsI.GET_BUGLIST_FAILED));
if (fetchProfiles) {
bugProfiles = (Hashtable) bugData.get("Profiles");
session.setAttribute("Profiles", bugProfiles);
// putting the stuff in the context
htStore.put("Profiles", bugProfiles);
htStore.put("SelectedProfile", new Integer(bugProfileId));
htStore.put("bugs", (ArrayList) bugData.get("Bugs"));
return htStore;
=============================================================
And I am trying to call this function as it can capable of fetching the data from the database by "getbugProfiles".
In the new class bugWatcherRefreshAction.java I have coded a part of code which actually clears the caching.Below I am giving the required part of the code:
=============================================================
public void doPerform(RunData rundata, Context context,String str) throws Exception {
JetspeedRunData data = (JetspeedRunData) rundata;
HttpServletRequest request = null;
//PortletConfig pc = portlet.getPortletConfig();
//String userId = request.getRemoteUser();
/*String userId = ((JetspeedUser)rundata.getUser()).getUserName();//sraha on 1/4/05
String pId = request.getParameter("PortletId");
PortalLogger.logDebug("just after pId " +pId); */
//Calling the variable holding the value of portlet id from BugWatcherAction.java
//We are getting the portlet id here , through a variable from BugWatcherAction.java
/*BugWatcherPortletContent bgAct = new BugWatcherPortletContent();
String portletID = bgAct.pId1;
PortalLogger.logDebug("got the portlet ID in bugwatcherRefreshAction:---sraha"+portletID);*/
// updating the bug groups
Hashtable result = new Hashtable();
try {
request = data.getRequest();
String userId = ((JetspeedUser)data.getUser()).getUserName();//sraha on 1/4/05
//String pId = (String)request.getParameter("portletId");
//String pId = pc.getPorletId();
PortalLogger.logDebug("just after pId " +pId);
PortalLogger.logDebug("after getting the pId-----sraha");
result =BugWatcherAPI.getbugList(profileId, userId);
PortalLogger.logDebug("select the new bug groups:: select is done ");
context.put("SelectedbugGroups", profileId);
//start clearing the cache
ContentCacheContext cacheContext = getCacheContext(rundata);
PortalLogger.logDebug("listBugWatcher Caching - removing markup content - before removecontent");
// remove the markup content from cache.
PortletContentCache.removeContent(cacheContext);
PortalLogger.logDebug("listBugWatcher Caching-removing markup content - after removecontent");
//remove the backend content from cache
CacheablePortletData pdata =(CacheablePortletData) PortletCache.getCacheable(PortletCacheHelper.getUserHandle(((JetspeedUser)data.getUser()).getUserName()));
PortalLogger.logDebug("listBugWatcher Caching User: " +((JetspeedUser)data.getUser()).getUserName());
PortalLogger.logDebug("listBugWatcher Caching pId: " +pId);
if (pdata != null)
// User's data found in cache!
PortalLogger.logDebug("listBugWatcher Caching -inside pdata!=null");
pdata.removeObject(PortletCacheHelper.getUserPortletHandle(((JetspeedUser)data.getUser()).getUserName(),pId));
PortalLogger.logDebug("listBugWatcher Caching -inside pdata!=null- after removeObject");
PortalLogger.logDebug("listBugWatcher Caching -finish calling the remove content code");
//end clearing the cache
// after clearing the caching calling the data from the database taking a fn from the portletContent.java
PortalLogger.logDebug("after clearing cache---sraha");
BugWatcherPortletContent bugwatchportcont = new BugWatcherPortletContent();
Hashtable httable= new Hashtable();
httable=(Hashtable)bugwatchportcont.loadContent();
PortalLogger.logDebug("after making the type casting-----sraha");
Set storeKeySet = httable.keySet();
Iterator itr = storeKeySet.iterator();
while (itr.hasNext()) {
String paramName = (String) itr.next();
context.put(paramName, httable.get(paramName));
PortalLogger.logDebug("after calling the databs data from hashtable---sraha");
} catch (CodedPortalException e) {
PortalLogger.logException("bugwatcherRefreshAction:: Exception- ",e);
context.put("Error", CommonUtil.getErrMessage(e.getMessage()));
catch (Exception e) {
PortalLogger.logException("bugwatcherRefreshAction:: Exception- ",e);
context.put(     "Error",CommonUtil.getErrMessage(ErrorConstantsI.EXCEPTION_CODE));
try {
((JetspeedRunData) data).setCustomized(null);
if (((JetspeedRunData) data).getCustomized() == null)
ActionLoader.getInstance().exec(data,"controls.EndCustomize");
catch (Exception e)
PortalLogger.logException("bugwatcherRefreshAction", e);
===============================================================
In the bugwatcher Action there is another function called PostLoadContent.java
here though i have found the portlet Id but unable to fetch that in the bugWatcherRefreshAction.java . I am also giving the code of that function under the bugWatcherAction.Java
================================================
// Get the PortletData object from intermediate store.
CacheablePortletData pdata =(CacheablePortletData) PortletCache.getCacheable(PortletCacheHelper.getUserHandle(
//rundata.getRequest().getRemoteUser()));
((JetspeedUser)rundata.getUser()).getUserName()));
pId1 = (String)portlet.getID();
PortalLogger.logDebug("in the bugwatcher action:"+pId1);
try {
Hashtable htStore = null;
// if PortletData is available in store, get current portlet's data from it.
if (pdata != null) {
htStore =(Hashtable) pdata.getObject(     PortletCacheHelper.getUserPortletHandle(
((JetspeedUser)rundata.getUser()).getUserName(),portlet.getID()));
//Loop through the hashtable and put its elements in context
Set storeKeySet = htStore.keySet();
Iterator itr = storeKeySet.iterator();
while (itr.hasNext()) {
String paramName = (String) itr.next();
context.put(paramName, htStore.get(paramName));
bugwatcherRefreshAction bRefAc = new bugwatcherRefreshAction();
bRefAc.doPerform(pdata,context,pId1);
=============================================================
So this is the total scenario for the fetching the data , after clearing the cache and display that in the portal.I am unable to do that.Presently it is still fetching the data from the cache and it is not going to the database.Even the portlet Id is returning as null.
I am unable to implement that thing.
If you have any insight about this thing, that would be great .As it is very urgent a promt response will highly appreciated.Please send me any pointers or any issues for this I am unable to do that.
Please let me know as early as possible.
Thanks and regards,
Santanu Raha.

Have you run it in a debugger? That will show you exactly what is happening and why.

Passing optional parameter to subreport

Hi,
I am having a CR 2008 report based on BW query. The query has optional parameter (the value can be set to NULL). When I try to use this report as subreport in my main report, I am unable to pass Null(equivalent to set to NULL) to my subreport using subreport link. I tried blank and "" in a formula field and try to link it to the subreport parameter but it doesn't work. Kindly guide me in this regard.
Thanks and Regards,
Subbu S

Hi Subbu,
Try to create a formula and pass the formula value to your sub report parameter and in sub report record selection based on main report formula value try to filter the records.
Ex: Main report create the following formula :
Whileprintingrecords;
Shared Stringvar x;
If not hasvalue({?Optional}) then
x:='No Value'
else
x:={?Optional}
Now link this to your sub report parameter
In sub report record selection
If {?parameter} = 'No Value ' then true else {?Parameter} = FieldValue.
Thanks,
Sastry

How to pass importing parameter of super class method to subclass method?

hi all,
i have defined a class
CLASS CUST_REPORT DEFINITION.
PUBLIC SECTION.
    METHODS:DATA_RETRIVE IMPORTING CUSTID_LOW TYPE ZCUSTOMER-ZCUSTID
                                   CUSTID_HIGH TYPE ZCUSTOMER-ZCUSTID.
    DATA:IT_CUST TYPE TABLE OF ZCUSTOMER,
         WA_CUST TYPE ZCUSTOMER.
ENDCLASS.                    "cust_report DEFINITION
The method DATA_RETRIVE   in this class has two importing parameters named CUSTID_LOW   and CUSTID_HIGH.
then i have defined subclas of this clas.
LASS CUST_ORD DEFINITION INHERITING FROM CUST_REPORT.
PUBLIC SECTION.
    DATA:IT_ORD TYPE TABLE OF ZORDER.
    METHODS:DATA_RETRIVE REDEFINITION,
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Method DATA_RETRIVE   is redefined.
So how to pass importing parameteres of super class method to sub class method with the same name.
Thanks and Regards,
Arpita

Hi,
I tried like this.
METHOD DATA_RETRIVE.
CALL METHOD SUPER->DATA_RETRIVE
      EXPORTING
        CUSTID_LOW = I_CUSTLOW
        CUSTID_HIGH = I_CUSTHIGH.
ENDMETHOD.
But parameters I_CUSTLOW and I_CUSTHIGH are not getting values after call to method.
Thanks and Regards,
Arpita

Pass a parameter in a class [(embed.....)]

Hello:
I have seen this code in ultitouch gesture samples. But I don't kno how can I pass a bitmap parameter to the stateme
nt [Embed(source="imagenes/prueba.jpg")],
please, can you tell me how can I use this code with other bitmaps using parameters in this class?
Many thanks to all of you.
package
     import flash.display.Bitmap;
     import flash.display.Sprite;
     import flash.events.TransformGestureEvent;
     import flash.text.TextField;
     import flash.text.TextFormat;
     import flash.ui.Multitouch;
     import flash.ui.MultitouchInputMode;
     import flash.events.TouchEvent;
     import flash.events.Event;
     import flash.display.Stage;
[SWF(width=320, height=480, frameRate=60, backgroundColor=0x000000)]
public class GestureExample extends Sprite
     [Embed(source="imagenes/prueba.jpg")]
     public var ElephantImage:Class;

ok still not really sure what you're after but you can embed 2 images
[Embed(source="imagenes/image1.jpg")]
public var Image1:Class;
[Embed(source="imagenes/image2.jpg")]
public var Image2:Class;
and then
create the 2 images
var image1:Bitmap = new Image1();
var image2:Bitmap = new Image2();
if you want to do this within a class you cna define a constructor
public class Foo
     [Embed(source="imagenes/image1.jpg")]
     public var Image1:Class;
     [Embed(source="imagenes/image2.jpg")]
     public var Image2:Class;
     public var image:Bitmap;
     public function Foo(image1:Boolean):void
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          else
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How to set no_value to Optional parameter in XI 3.0 by OpenDoc URL linking

I found in "BusinessObjects XI 3.0 Viewing reports and documents using URLs Howto.doc"
"You can remove an optional parameter from the prompt by setting it to no_value in the OpenDocument query string."
I tested: response.sendRedirect("/OpenDocument/opendoc/openDocument.jsp?sIDType=CUID&iDocID=AaVxpKuKNBxKnHUJCqwuRi0&lsSCountry=""no_value""&token=" + logonToken);
But it will filter no data, because no country call "no_value". I still need to delete the value, and click Apply, to get all data.
I wonder how to achieve optional parameter via opendocument linking, to get a report with "full data set".
Any one can help?
Thanks in advance!
Jennie

Hi Jennie,
I'm wondering if "1203675 - Cannot specify an empty string for an optional string parameter through the refresh prompts page which displays "no value" unlike the parameter panel" is related to this.
Instead of using no value or empty string, how about if you use ALL value for the parameter to bring full data? Check "1218621 - Option "All" in list of values for a dynamic prompt in XI"
Hitomi

Passing an array method to a constructor

I'm studying Java this summer (in NZ) and having a bit of trouble with an exersize in my book, the lab isn't open for marking at the moment, so I'm trying to do it at home.
I have a method readArray in the application method, which returns an array. I wish to pass it to the support class Constructor, and have the constructor store the array as instance data so I can sort it later. I can pass it fine by doing:
ReadData data = new ReadData(readArray());
from the main method.
However, I don't know how to store it as instance data, this is all I have so far within the support class:
private int[] array;
public ReadData(int[]array){
this.array[] = array[];
However, while compiling i get an error: not a statement. I am pretty certain that I simply have done it wrong. Can someone give me a hand?

is this what you are trying to do?
i think the following will help you
class Demo {
     private int arr [] = new int[10];
     public Demo(){
     public Demo(int arr[]){
          this.arr = arr;
     public void printArr(){
          for(int i =0;i<arr.length;i++){
               System.out.println(" "+arr);
public class Test{
     public static void main(String args[]){
          Test t = new Test();
          Demo d = new Demo(t.readArray());
          d.printArr();
     public int[] readArray(){
          int arr[]= {10,20,30,40,50,60,70,80,90,100};
          return arr;

Set fields of derived class in base class constructor via reflection?

Does the Java Language Specification explicitly allow setting of fields of a derived class from within the base class' constructor via reflection? The following test case runs green, but I would really like to know if this Java code is compatible among different VM implementations.
Many thanks for your feedback!
Norman
public class DerivedClassReflectionWorksInBaseClassConstructorTest extends TestCase {
abstract static class A {
    A() {
        try {
            getClass().getDeclaredField("x").setInt(this, 42);
        } catch (Exception e) {
            throw new RuntimeException(e);
static class B extends A {
    int x;
    B() {
    B(int x) {
        this.x = x;
public void testThatItWorks() {
    assertEquals(42, new B().x);
    assertEquals(99, new B(99).x);
}

why not just put a method in the superclass that the subclasses can call to initialize the subclass member variable?In derived classes (which are plug-ins), clients can use a field annotation which provides some parameter metadata such as validators and the default value. The framework must set the default value of fields, before the class' initializer or constructors are called. If the framework would do this after derived class' initializer or constructors are called, they would be overwritten:
Framework:
public abstract class Operator {
    public abstract void initialize();
}Plug-In:
public class SomeOperator extends Operator {
    @Parameter(defaultValue="42", interval="[0,100)")
    double threshold;
    @Parameter(defaultValue="C", valueSet="A,B,C")
    String mode;
    public void setThreshold(double threshold) {this.threshold = threshold;}
    public void setMode(String mode) {this.mode = mode;}
    // called by the framework after default values have been set
    public void initialize() {
}On the other hand, the default values and other metadata are also used to create GUIs and XML I/O for the derived operator class, without having it instantiated. So we cannot use the initial instance field values for that, because we don't have an instance.

How to pass this multi-value parameter via GoURL?

Currency is equal to / is in 'USD', 'GBR', 'RUR'. How to pass such multi-value parameter via GoURL?
P0=1&P1=eq&P2=Measures.Currency&P3=?

Found. P0=1&P1=eq&P2=Measures.Currency&P3=3+USD+GBR+RUR

Passing select option parameter to a procedure

Hello, i need to know pass a select option parameter to a procedure. I tried the following
For eg if i have a select option called so_belnr & i call the procedure using the following
PERFORM VALIDATE_DOCUMENT TABLES SO_BELNR USING GJAHR BUKRS , i still cannot use the
select option paramter in the called procedure.
Pls help.

Hi,
in topinclude...
data: lr_belnr type RNG_BELNR.
at start-of-sel.....
move so to range..
refresh: lr_belnr.
lr_belnr[] = so_belnr[].
PERFORM VALIDATE_DOCUMENT TABLES lr_belnr USING GJAHR BUKRS .
in form:
... tables lr_belnr like structure of RNG_BELNR.
reason(my definietion): perfom doesn´t know if the select-options is availible.....
bestreg
Robert

Select-option parameter passed to function module

hi,
I have passed the select-option parameter as a table to my function module,
suppose i have passed it as date(it contains field date-high and date-low)
In my function module while i am looping the table and selecting the data according to date_low,it is going to select only the data according to date_low.
since the table contains only one row.
loop at date.
select the data according to date_low.
date_low = date_low +1.
modify date_low.
endloop.
how can i select all the data from date_low and date_high?

Hi,
there is issue design of ur FM .
You have to put 2 table parametrs or 2 import paremeters in the FM ,after that with in the Function module fill the internal table of type ranges (say itab).
After filling the ranges internal table, this can be used in ur select stament just as select option ( select ...where podat in itab)
revrt back if any issues.
regards,
Naveen

Inherit / extend class calls constructor...

Hi,
Class A extends class B like so:
public class A extends B{}
Why is class B's constructor called? I thought when A extends
B, A gets all of B's methods and variables, great; but I don't need
the constructor called because class B has already been created. I
just want class A to inherit all of B's methods and variables. Can
a class have two constructors, so when I extend class B an empty
constructor is called but when I instantiate it the constructor
with code is called?
I feel like I’m missing something here.
Thanks,
4dplane

Yep you are missing something. :)
The constructor is just that -- it builds each instance of
the class, puts it together if you will. Without a call to the
superclass's constructor you won't get all its properties, methods,
etc.
You'll notice that the B constructor is even call first. That
is to make sure that everything is ready and accessable to A
It sounds like whatever you are trying to do isn't really a
good candidate for extension.. Fill us in a bit more and perhaps we
can come up with some ideas..

Class field initialization outside class constructor

Hi,
what are the benefits of initializing a class field outside the class constructor? I use this for fields, that i do not need to pass parameter to via the constructor. The code seems more clear/easy to read.

Hi,
what are the benefits of initializing a class field
outside the class constructor? I use this for
fields, that i do not need to pass parameter to via
the constructor.
The code seems more clear/easy to read.That's a pretty big benefit.
For another, consider when you have multiple constructors: you've factored
common code out of them (good) and made it impossible to forget to
initialize that field later when, later on, you write another constructor(also good).

More:Could u pls complete the following code by adding a class constructor?

Thank you for your concern about my post. Actually it is an exercise in book "Thinking in Java, 2nd edition, Revision 12" chapter 8. The exercise is described as below:
Create a class with an inner class that has a nondefault constructor. Create a second class with an inner class that inherits from the first inner class.
And I make some changes for the above exercise requiring the class which encloses the first inner class has a nondefault constructor.
There is something related to this topic in chapter 8 picked out for reference as below:
Inheriting from inner classes
Because the inner class constructor must attach to a reference of the enclosing class object, things are slightly complicated when you inherit from an inner class. The problem is that the �secret?reference to the enclosing class object must be initialized, and yet in the derived class there�s no longer a default object to attach to. The answer is to use a syntax provided to make the association explicit:
//: c08:InheritInner.java
// Inheriting an inner class.
class WithInner {
class Inner {}
public class InheritInner
extends WithInner.Inner {
//! InheritInner() {} // Won't compile
InheritInner(WithInner wi) {
wi.super();
public static void main(String[] args) {
WithInner wi = new WithInner();
InheritInner ii = new InheritInner(wi);
} ///:~
You can see that InheritInner is extending only the inner class, not the outer one. But when it comes time to create a constructor, the default one is no good and you can�t just pass a reference to an enclosing object. In addition, you must use the syntax
enclosingClassReference.super();
inside the constructor. This provides the necessary reference and the program will then compile.
My previous post is shown below, could you help me out?
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
//Could you please help me complete the following code by generating
// the Test class constructor to ensure error free compilation? Please
// keep the constructor simple just to fulfill its basic functionality
// and leave the uncommented part untouched.
class Outer {
Outer (int i) {
System.out.println("Outer is " + i);
class Inner {
int i;
Inner (int i) {
this.i = i;
void prt () {
System.out.println("Inner is " + i);
public class Test extends Outer.Inner {
// Test Constructor
// is implemented
// here.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Test(Outer o, int i) {
o.super(i);
}Note that this doesn't quite answer the question from Thinking In Java, since your Test class is not an inner class (though there is no difference to the constructor requirements if you do make it an inner class).

Can't get extended class to work with asbstract class

I am having trouble working an extended class to work with my base abstract class. I keep getting this error message: "Fiction.java:4: invalid method declaration; return type required" public FictionBook()" Can someone give me some advice and or guidance on what I need to do? Thanks.
Here is my abstract class:
import javax.swing.*;
public abstract class Book
     protected String bookTitle;
     protected double bookPrice;
     public abstract double setPrice();
public Book()
          setBookPrice();
public double getBookPrice()
          return bookPrice;
public abstract void setBookPrice();
Here is the extended class that I have:
import javax.swing.*;
public class Fiction extends Book
     public Fiction()
          super();
          setBookPrice();
     public void setBookPrice();
          bookPrice = 24.95;
     public String toString()
          return("Fiction Book Price is $" + bookPrice);
}

Fiction.java:2: Fiction is not abstract and does not override abstract method setPrice() in BookThis one is pretty straightfoward: Book declares an abstract setPrice() method. In effect is promises "every concrete subclass of Book will define an implementation of setPrice()". But your Fiction class does not do this - it does not give an implementation of setPrice() even though as a Book it is required to do so. That is what the compiler is complaining about.
Fiction.java:6: call to super must be first statement in constructorThis one is slightly cryptic. If you use super() it must be as the first line of a constructor. You are using it as the first line of Fiction() so that looks OK - until you realise that Fiction() is not a constructor! That's because you declare it as a method returning void. Remove the "void" and the compiler will recognise it as a constructor and will be happy about your use of super().
Edited by: pbrockway2 on Sep 13, 2008 12:13 PM
Just a general point: it might be worth writing very brief comments for your abstract class to say what the methods are supposed to do. It isn't really clear what setBookPrice() is supposed to do given that it isn't passed any argument. Likewise setPrice(), how does it differ from setBookPrice()? what is the double value that it returns?

Passing Optional Parameter Via Extended Class Constructor

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