Casting TreeMap.Values() return value

Hi,
I'm working on an application that its main content is an object of type Instument.
Each Instrument has different attributes, one of them is its name. The names of the instruments must by unique.
In order to group all the Instruments, there is a second class names InstrumentSet. The main variable of this class (called allInstruments) is of type TreeMap<String, Instrument>, where the Instruments' names are the keys. One (static) method of this class is called 'getAllElements()' and it returns all the elements by calling the simple values() method which is a member of the TreeMap class. The return type is a the one returned by the 'values()" method - Collection<E>.
I would like to keep a reference to this set of elements, so I tried the following (this is part of the getAllElements() method):
{code}
Collection<Instrument> c = allInstruments.values();
ArrayList<Instrument> li = (ArrayList<Instrument>)c;
{code}
But it fails when run, throwing the following exception:
{code}java.lang.ClassCastException: java.util.TreeMap$Values cannot be cast to java.util.List{code}
Without a cast, if fails during compilation.
Since I still lack some generics knowledge, and all the exampel regarding the values() method deal only with iterating it, but not assigning its return value, I'm quite lost.
Can anyone enlight me with this issue?

Hi Kaj & alan_mehio,
Neither do I see any difference between the two lines.
As for the questions you asked:
1 - The Instruments are shown in a JTable. It seems to me more 'programmer friendly' to use a local reference to the set of elements instead of calling time after time to the values(). This for the first question.
2 - You know, while searching for a solution, I thought about something like
Collection<Instrument> c = allInstruments.values();but it's seems very 'general'. In a way, like declaring all the references in a program as of type Object. I guess I just was wrong, believing I can do something more specific with the values() return value.
Thanks you both for you time and effort and all the best,
Doron

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TABLE(CAST()) function not returning the correct results in few scenarios.

I am using TABLE(CAST()) operation in PL/SQL and it is returning me no data.
Here is what I have done:
1.     Created Record type
CREATE OR REPLACE TYPE target_rec AS OBJECT
target__id          NUMBER(10),
target_entity_id NUMBER(10),
dd           CHAR(3),
fd           CHAR(3),
code      NUMBER(10),
target_pct      NUMBER,
template_nm VARCHAR2(50),
p_symbol      VARCHAR2(10),
pm_init          VARCHAR2(3),
target_name     VARCHAR2(20),
targe_type     VARCHAR2(30),
target_caption     VARCHAR2(30),
sort_order      NUMBER (4)
2.     Created Table type
CREATE OR REPLACE TYPE target_arr AS TABLE OF target_rec
3.     Created Stored procedure which accepts parameter of type target_arr and runs the Table(Cast()) function on it.
     Following is the simplified form of my procedure.
     PROCEDURE get_target_weights
     p_in_template_target IN target_arr,
     p_out_count          OUT NUMBER,
     IS
     BEGIN
          SELECT count(*) into p_out_count
     FROM TABLE(CAST(p_in_template_target AS                     target_arr)) arr;
     END;
I am calling get_target_weights from my java code and passing p_in_template_target with 10140 records.
Scenario 1: If target_pct in the last record is 0, p_out_count returned from the procedure is 0.
Scenario 2: If target_pct in the last record is any other value(say 0.01), p_out_count returned from the procedure is 10140.
Please help me understand why the Table(Cast()) is not returning the correct results in Scenario 1. Also adding or deleting any record from the test data returns the correct results (i.e. if keep target_pct in the last record as 0 but add or delete any record).
Let me know how can I attach the test data I am using to help you debugging as I don’t see any Attach file button on Post Message screen on the forum.

I am not able to reproduce this problem with a small data set. I can only reproduce with the data having 10140 records.
I am not sure if this is the memory issue as adding a new record also solves the problem.
This should not be the error because of wrong way of filling the records in java as for testing purpose I just saved the records which I am sending from java in a table. I updated the stored procedure as well to read the data from the table and then perform TABLE(CAST()) operation. I am still getting 0 as the output for scenario 1 mentioned in my last mail.
Here is what I have updated:
1.     Created the table target_table
CREATE Table target_table
target_id          NUMBER(10),
target_entity_id NUMBER(10),
dd           CHAR(3),
fd           CHAR(3),
code      NUMBER(10),
target_pct      NUMBER,
template_nm VARCHAR2(50),
p_symbol      VARCHAR2(10),
pm_init          VARCHAR2(3),
target_name     VARCHAR2(20),
target_type     VARCHAR2(30),
target_caption     VARCHAR2(30),
sort_order      NUMBER (4)
2.     Inserted data into the table : The script has around 10140 rows. Pls let me know how can I send it to you
3.     Updated procedure to read data from table and stored into variable of type target_arr. Run Table(cast()) operation on target_arr and get the count
PROCEDURE test_target_weights
IS
     v_target_rec target_table%ROWTYPE;
     CURSOR wt_cursor IS
     Select * from target_table;
     v_count NUMBER := 1;
     v_target_arr cws_target_arr:= target_arr ();
     v_target_arr_rec target_rec;
     v_rec_count NUMBER;
     BEGIN
     OPEN wt_cursor;
     loop
          fetch wt_cursor into v_target_rec; -- fetch data from table into local           record.
          exit when wt_cursor%notfound;
          --move data into target_arr
          v_target_arr_rec :=                     cws_curr_pair_entity_wt_rec(v_target_rec target_id,v_target_rec. target_entity_id,
                    v_target_rec.dd,v_target_rec.fd,v_target_rec.code,v_target_rec.target_pct,
     v_target_rec.template_nm,v_target_rec.p_symbol,v_target_rec.pm_init,v_target_rec.template_name,
     v_target_rec.template_type,v_target_rec.template_caption,v_target_rec.sort_order);
          v_target_arr.extend();
          v_target_arr(v_count) := v_target_arr_rec;
          v_count := v_count + 1;
     end loop;
     close wt_cursor;
     -- run table cast on target_arr
     SELECT count(*) into v_rec_count
     FROM TABLE(CAST(v_target_arr AS target_arr)) arr;
     DBMS_OUTPUT.enable;
     DBMS_OUTPUT.PUT_LINE('p_out_count ' || v_rec_count);
     DBMS_OUTPUT.PUT_LINE('v_count ' || v_count);
END;
Output is
p_out_count 0
v_count 10140
Expected output
p_out_count 10140
v_count 10140

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Hi,
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at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
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If you run this code in a stand alone program, this problem doesn't happen. It only happen when running in the web server.
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Thanks,
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I'm not familiar with any specifics of IBM's implementation but from an EJB 3 spec perspective there is no need to use PortableRemoteObject.narrow() if you're retrieving an EJB 3.0 Remote Business interface, regardless of the component type( stateful vs. stateless). In addition, the "_Stub" class should never have to be part of your client programming model. That should be hidden within the vendor's implementation, if present at all.
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@Remote
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I am wondering what is the best way to change a value in a TreeMap? I have retrieved a value by .get on the key i.e.
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type_cast_crazy.vi ‏13 KB

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Hello,
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Client code cast error:EJB returning data in Collection of Objects

Still trying to understand this EJB stuff.....
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regards
srini

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I have a simple report with two column. The query is as below.
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FROM applicationformdtl
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caste total
sc/st 3
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throw new RuntimeException(clz + " is not assignable from " + value.getClass()) ;
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Not many languages can take this into consideration. In a way, it makes the return type part of the signature.
Advantages:
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- Members can be treated uniformly, such a through iteration
Disadvantages:
- Involve the confusing zero-length var-args in the api that must be ignored
- Type is inferred to be Object when the return value is not assigned
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Edited by: crackleOK on Jul 21, 2009 4:46 AM

crackleOK wrote:
JoachimSauer wrote:
The only redeeming quality is that it can be very nice to use such code.API's are to use (and often have ugly guts). Unfortunately true, but not a good reason to write ugly implementation code. If you only care about code quality up to the API, then you only care about the shiny coating of your car as well and don't mind the rust as long as you don't see it.
As I said: sometimes the tradeoff is worth it, but it should still be weighted.
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public <T> T get(String name, T...ts)
// with
public <T> T get(String name)without any loss of functionality.

How to cast a fieldinput value to upper case.

Im not a java programer I guess that this must be a silly thing.
Im searching data in R/3 from 2 fields 1 numeric and the other alphanumeric. This alphanumeric fields if I put it in upper case works, if I wirte it in lower case doesnt works.
In R/3 when I test the FM doesnt matter if I put it lower or upper case, it works fine.
so I wanna know how can I in WD cast the value that I put in that fieldinput be converted to upper case when I hit the search button.
Thx

> Im not a java programer I guess that this must be a
> silly thing.
>
> Im searching data in R/3 from 2 fields 1 numeric and
> the other alphanumeric. This alphanumeric fields if I
> put it in upper case works, if I wirte it in lower
> case doesnt works.
>
> In R/3 when I test the FM doesnt matter if I put it
> lower or upper case, it works fine.
>
> so I wanna know how can I in WD cast the value that I
> put in that fieldinput be converted to upper case
> when I hit the search button.
>
> Thx
Hi,
When you test the FM in SE37 in R3 there is an option at the top of the screen Called Uppercase/Lowercase - this controls whether the input is automatically converted to upper case for alphanumeric fields.
The other option you have, if it is a custom FM, is to translate the input of the alphanumeric fields in the ABAP - it is quite common to have to translate or convert input data to make sure it is in the same format as the backend system.
I prefer to do this sort of conversion on the backend system as usually you have a better guarentee that it will be in the correct format, than if you do it in the Java element.
Just my opinion,
Gareth.

Error while reading UcdContext [trying to read / set application values for users]

Hi,
I am trying to write a program to store user selected values on NW7.3 Portal using "User Content Directory". I can see and read some code snippets on how to set and read the context but I am getting one error after another.
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1) I tried different ways to have a lookup and always gave message as "look up not found" and for pcd:portal_content came up with above error.
2) Once I read the UCD context, I would like to store some values based on user selection and store them. User may change the values whenever they like and I will be using the values for other purposes in another application.
3) Has any one successful in setting and reading UCD Context in NW 7.3. Will it be possible to share such sample code as the code snippets at http://help.sap.com/saphelp_nw73ehp1/helpdata/en/4a/8e1bce28e24dd8abd9f4de05e5587d/content.htm are not much of use unless I am able to read the UCD.
Thanks for your help!
Regards,
Raju
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InitialContext initialContext = null;
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env.put(UCD_INITIAL_CONTEXT_FACTORY, UCD_INITIAL_CONTEXT_FACTORY);
env.put(Context.SECURITY_PRINCIPAL, request.getUser());
env.put(Constants.REQUESTED_ASPECT, IPcdAttribute.PERSISTENCY_ASPECT);
try{
initialContext = new InitialContext(env);
//response.write("Before pcdCtx lookup");
try {
pcdCtx = (com.sapportals.portal.pcd.gl.PcdGlContext) initialContext.lookup("pcd:portal_content");
} catch(Exception e){
response.write("Some problem with lookup" + e.getMessage());

Hi,
There are quite few differences in the standard code snippet given by SAP Help on UCD and the once that you put above in the question.
Below is standard snippet.
Hashtable<Object, Object> env = new Hashtable<Object, Object>();
env.put(Context.INITIAL_CONTEXT_FACTORY,
IPcdContext.UCD_INITIAL_CONTEXT_FACTORY);
env.put(Context.SECURITY_PRINCIPAL, user);
InitialContext ctx = new InitialContext(env);
pcdCtx = (IPcdContext) ctx.lookup("");
============================
Check the ones highlighted in BOLD and compare them in your code. In your code when ur doing initial lookup you are not using the Correct class type cast for the returned lookup object!
Your code shows as below:
pcdCtx = (com.sapportals.portal.pcd.gl.PcdGlContext) initialContext.lookup("pcd:portal_content");
But may be it shd have been something like below:
pcdCtx = (IPcdContext) initialContext.lookup("pcd:portal_content");
Pls verify and hopefully this resolves your issues around look up.
Thanks,
Swapna Priya.

Casting TreeMap.Values() return value

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