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Java how to get rid of redundant code

In Java I parse a XML document. This XML is a Purchase Order and from this XML I create a PO document in our ERP-system.
I use domparser to parse the XML.
So eventually I have code like this:
--this is an excerpt --
//ShipTo
Element shipToElement = CXMLHandlerObj.getChildElement(elementOrderRequestHeader, "ShipTo");
//Address
Element shipToAddressElement = CXMLHandlerObj.getChildElement(shipToElement, "Address");
/*get attributes of Address*/
notesHandlerObj.docOrder.replaceItemValue("ShipToParty_addressID", shipToAddressElement.getAttribute("addressID"));
notesHandlerObj.docOrder.replaceItemValue("ShipToParty_addressIDDomain", shipToAddressElement.getAttribute("addressIDDomain"));
notesHandlerObj.docOrder.replaceItemValue("ShipToParty_isoCountryCode", shipToAddressElement.getAttribute("isoCountryCode"));
But the XML also contains at the top a OrderRequestHeader which has a type attribute in it:
<OrderRequestHeader orderDate="2017-04-04T12:00:00+00:00" orderID="4550144777" orderType="regular" orderVersion="1" type="new">
Below this element all the details of the order are found.
The "type" attribute can have values like : New or Update.
The type will be "new" if the PO XML is send for the first time and the type will be "update" if the same PO is sent but then with an update contained within it.
Note that the XML structure is the same but only the type is different.
When the type is "New", I will just parse the XML and create the PO document. But if the type is "Update" then I want to check every element and update the document and mail the changes accordingly..
Now the problem is that for the parsing of the XML I need to create a new PO or update an existing one. This I can do by the following ways:
1. creating two methods :
1. create new PO
2. update PO
In the create method I can parse the xml and add values from element to the document.
In the update method I can parse again all elements but also check which data has been changed.
2. I can put a if and else statement before every element
The methods of above are a bit redudant is there any simpler way of doing this?

Java XML Parsing into object

We have a requirement of parsing xml data in java.
The xml data looks like this:
xml_data
1> The first question here is how to parse such data.I have tried the code suggested in this link :
xmlparse with Node
and have partial success. The only doubt here is how can i can to reach "" tag.
2>The second question is if the data is parsed how can we can store the values in single object,so that we can get length and values of "CRAWL", "Test", "Check"(Tables) separately(from single object)?
Please help me as how can we achieve this?
Abhi

Extracting Element Value from jPOS ISO

I am trying to extract a value within an ISO String which I get from a jPOS Structured Data. The string looks like this:
221ThirdPartyBillPayment3125
<ThirdPartyBillPayment>
<BillPaymentRequest>
<ReferenceId>1111111111</ReferenceId>
</BillPaymentRequest>
</ThirdPartyBillPayment>
Is there a way I can get the value "1111111111" of ReferenceId node?

The sample data is a postilion structured data field which uses kind of a TLV (tag length value format).
221ThirdPartyBillPayment3125
<ThirdPartyBillPayment>
<BillPaymentRequest>
<ReferenceId>1111111111</ReferenceId>
</BillPaymentRequest>
221ThirdPartyBillPayment
Here 2 is the length of length (21), 21 is the length of the tag ThirdPartyBillPayment
3125
<ThirdPartyBillPayment>
<BillPaymentRequest>
<ReferenceId>1111111111</ReferenceId>
</BillPaymentRequest>
</ThirdPartyBillPayment>
Here 3 is the length of length (125), 125, is the length of data to follow.
You could write code to get access to xml iteratively for all thats available in structured data and then parse out the xml data within.
Or
You could ask Postilion for the dtd/schema for the xml used in their structured data iso field and use jaxb to access the data.
It will boil down to a name value pair
ThirdPartyBillPayment= <ThirdPartyBillPayment><BillPaymentRequest<ReferenceId>1111111111</ReferenceId></BillPaymentRequest>
</ThirdPartyBillPayment>

You've got some custom data in a mix of some fixed fields and some XML there, so you first need to get the whole field off your ISOMsg, i.e:
String s = m.getString("127.1"); // provided your data comes in field 127.1
Then figure out where the XML starts (in this case, at indexOf('<')), then you need feed that XML in an XML parser (you can use jdom that comes as a jPOS dependency), parse the XML and get the child element ReferenceId.

How to write a http get request when a key's value is an array?

I have written a java servlet to deal with http get request.I know ,the common format of get request is like this:http://IP_ADDRESS:8080/test?name="jack"&value="shit.
But now ,I have a list of values to transfer,such as an user id list[1,2,3,4].So ,my question is ,how should I write my http get request to express this?And in java servets doGet(),can I use request.getParameterValues to get such an array?

if you are using GET method your url should be looking like that :
http://IP_ADDRESS:8080/test?list=1&list=2&list=3
for retrieving it:
String[] arrlist=request.getParameterValues('list');
your array will be filled with separated values:
//["1","2","3"]
UPDATE : if to write it list[] or list?
when you retrieving your list parameters it wouldn't be parsed as array but as a series of String which will be grouped later on into an array.
Which means even if you write it list[]=1&list[]=2&list[]=3, list[=1&list[=2&list[=3, list*=1&list*=2&list*=3 or list=1&list=2&list=3 it would always be giving you the same answer whether you retrieve it as
request.getParameterValues('list[]') //["1","2","3"]
request.getParameterValues('list[') //["1","2","3"]
request.getParameterValues('list*') //["1","2","3"]
request.getParameterValues('list') //["1","2","3"]

While ,the http request format should be like this:localhost:8080/test?list[]=1&list[]=2&list[]=3

Maybe too simple, but what about repeat parameters name?
http://IP_ADDRESS:8080/test?userId=1&userId=2&userId=3

retrieving the values from the nested hashmap

I have a XML file with many copies of table node structure as below:
<databasetable TblID=”123” TblName=”Department1_mailbox”>
<SelectColumns>
<Slno>dept1_slno</Slno>
<To>dept1_to</To>
<From>dept1_from</From>
<Subject>dept1_sub</Subject>
<Body>dept1_body</Body>
<BCC>dept1_BCC</BCC>
<CC>dept1_CC</CC>
</SelectColumns>
<WhereCondition>MailSentStatus=’New’</WhereCondition>
<UpdateSuccess>
<MailSentStatus>’Yes’</MailSentStatus>
<MailSentFailedReason>’Mail Sent Successfully’</MailSentFailedReason>
</UpdateSuccess>
<UpdateFailure>
<MailSentStatus>’No’</MailSentStatus>
<MailSentFailedReason>’Mail Sending Failed ’</MailSentFailedReason>
</ UpdateFailure>
</databasetable>
As it is not an efficient manner to traverse the file for each time to fetch the details of each node for the queries in the program, I used the nested hashmap concept to store the details while traversing the XML file for the first time. The structure I used is as below:
MapMaster
Key Value
123 MapDetails
Key Value
TblName Department1_mailbox
SelectColumns mapSelect
Key Value
Slno dept1_slno
To dept1_to
From dept1_from
Subject dept1_sub
Body dept1_body
BCC dept1_BCC
CC dept1_CC
WhereCondition MailSentStatus=’New’
UpdateSuccess mapUS
MailSentStatus ’Yes’
MailSentFailedReason ’Mail Sent Successfully’
UpdateFailure mapUF
MailSentStatus ’No’
MailSentFailedReason ’Mail Sending Failed’
But the problem I’m facing now is regarding retrieving the Value part using the nested Keys. For example,
If I need the value of Slno Key, I have to specify TblID, SelectColumns, Slno in nested form like:
Stirng Slno = ((HashMap)((HashMap)mapMaster.get(“123”))mapDetails.get(“SelectColumns”))mapSelect.get(“Slno”);
This is unconvinent to use in a program. Please suggest a solution but don’t tell that iterators are available. As I’ve to fetch the individual value from the map according to the need of my program.
EDIT:my program has to fetch the IDs of the department for which there is privilege to send mails and then these IDs are compared with the IDs in XML file. Only information of those IDs are fetched from XML which returned true in comparison. This is all my program. Please help.
Thanks in advance,
Vishu

Never cast to specific Map implementation. Better use casting to Map interface, i.e.
((Map)one.get("foo")).get("bar")
Do not use casting in your case. You can define collection using generics, so compiler will do work for you:
Map<String, Map> one = new HashMap<String, Map>();
Map<String, Integer> two = new HashMap<String, Integer>();
Now your can say:
int n = one.get("foo").get("bar");
No casting, no problems.
But the better solution is not to use nested tables at all. Create your custom classes like SelectColumns, WhereCondition etc. Each class should have appropriate private fields, getters and setters. Now parse your XML creating instance of these classes. And then use getters to traverse the data structure.
BTW if you wish to use JAXB you do not have to do almost anything! Something like the following:
Unmarshaller u = JAXBContext.newInstance(SelectColumns.class, WhereCondition.class).createUnmarshaller();
SelectColumns[] columns = (SelectColumns[])u.unmarshal(in);

One approach to take would be to generate fully qualified keys that contain the XML path to the element or attribute. These keys would be unique, stored in a single hashmap and get you to the element quickly.
Your code would simply have to generate a unique textual representation of the path and store and retrieve the xml element based on the key.