How to make sorting in hash table efficient

Hi guys,
I am relatively new to collections.
I have a HashTable which has 100000 records in it, when I sort it, it takes a lot of time to get it done.
As the Hashtable methods are synchronised so even I can't use threads to perform this quickely for me.
Can any one provide any solution using multi threading or any other method to achieve the optimization in
sorting the hashtable.
Thanks,
Atul

As already suggested, use TreeMap if you want to build your table in sorted key order. Otherwise, if you want to sort after the fact, you could do one of the following:
SortedSet sortedKeys = new TreeSet(map.keySet());
// or
List sortedKeys = new TreeSet(map.keySet());
Collections.sort(sortedKeys);Note that this will NOT affect that order in the map. It only affects the order of the extracted keys.
Also not that if sorting 100,000 items is taking "a long time," then you probably wrote your own sort algorithm and it's probably O(n^2) or something.

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How to make column headers in table in PDF report appear bold while datas in table appear regular from c# windows forms with sql server2008 using iTextSharp

Hi my name is vishal
For past 10 days i have been breaking my head on how to make column headers in table appear bold while datas in table appear regular from c# windows forms with sql server2008 using iTextSharp.
Given below is my code in c# on how i export datas from different tables in sql server to PDF report using iTextSharp:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Data.SqlClient;
using iTextSharp.text;
using iTextSharp.text.pdf;
using System.Diagnostics;
using System.IO;
namespace DRRS_CSharp
public partial class frmPDF : Form
public frmPDF()
InitializeComponent();
private void button1_Click(object sender, EventArgs e)
Document doc = new Document(PageSize.A4.Rotate());
var writer = PdfWriter.GetInstance(doc, new FileStream("AssignedDialyzer.pdf", FileMode.Create));
doc.SetMargins(50, 50, 50, 50);
doc.SetPageSize(new iTextSharp.text.Rectangle(iTextSharp.text.PageSize.LETTER.Width, iTextSharp.text.PageSize.LETTER.Height));
doc.Open();
PdfPTable table = new PdfPTable(6);
table.TotalWidth =530f;
table.LockedWidth = true;
PdfPCell cell = new PdfPCell(new Phrase("Institute/Hospital:AIIMS,NEW DELHI", FontFactory.GetFont("Arial", 14, iTextSharp.text.Font.BOLD, BaseColor.BLACK)));
cell.Colspan = 6;
cell.HorizontalAlignment = 0;
table.AddCell(cell);
Paragraph para=new Paragraph("DCS Clinical Record-Assigned Dialyzer",FontFactory.GetFont("Arial",16,iTextSharp.text.Font.BOLD,BaseColor.BLACK));
para.Alignment = Element.ALIGN_CENTER;
iTextSharp.text.Image png = iTextSharp.text.Image.GetInstance("logo5.png");
png.ScaleToFit(105f, 105f);
png.Alignment = Element.ALIGN_RIGHT;
SqlConnection conn = new SqlConnection("Data Source=NPD-4\\SQLEXPRESS;Initial Catalog=DRRS;Integrated Security=true");
SqlCommand cmd = new SqlCommand("Select d.dialyserID,r.errorCode,r.dialysis_date,pn.patient_first_name,pn.patient_last_name,d.manufacturer,d.dialyzer_size,r.start_date,r.end_date,d.packed_volume,r.bundle_vol,r.disinfectant,t.Technician_first_name,t.Technician_last_name from dialyser d,patient_name pn,reprocessor r,Techniciandetail t where pn.patient_id=d.patient_id and r.dialyzer_id=d.dialyserID and t.technician_id=r.technician_id and d.deleted_status=0 and d.closed_status=0 and pn.status=1 and r.errorCode<106 and r.reprocessor_id in (Select max(reprocessor_id) from reprocessor where dialyzer_id=d.dialyserID) order by pn.patient_first_name,pn.patient_last_name", conn);
conn.Open();
SqlDataReader dr;
dr = cmd.ExecuteReader();
table.AddCell("Reprocessing Date");
table.AddCell("Patient Name");
table.AddCell("Dialyzer(Manufacturer,Size)");
table.AddCell("No.of Reuse");
table.AddCell("Verification");
table.AddCell("DialyzerID");
while (dr.Read())
table.AddCell(dr[2].ToString());
table.AddCell(dr[3].ToString() +"_"+ dr[4].ToString());
table.AddCell(dr[5].ToString() + "-" + dr[6].ToString());
table.AddCell("@count".ToString());
table.AddCell(dr[12].ToString() + "-" + dr[13].ToString());
table.AddCell(dr[0].ToString());
dr.Close();
table.SpacingBefore = 15f;
doc.Add(para);
doc.Add(png);
doc.Add(table);
doc.Close();
System.Diagnostics.Process.Start("AssignedDialyzer.pdf");
if (MessageBox.Show("Do you want to save changes to AssignedDialyzer.pdf before closing?", "DRRS", MessageBoxButtons.YesNoCancel, MessageBoxIcon.Exclamation) == DialogResult.Yes)
var writer2 = PdfWriter.GetInstance(doc, new FileStream("AssignedDialyzer.pdf", FileMode.Create));
else if (MessageBox.Show("Do you want to save changes to AssignedDialyzer.pdf before closing?", "DRRS", MessageBoxButtons.YesNoCancel, MessageBoxIcon.Exclamation) == DialogResult.No)
this.Close();
The above code executes well with no problem at all!
As you can see the file to which i create and save and open my pdf report is
AssignedDialyzer.pdf.
The column headers of table in pdf report from c# windows forms using iTextSharp are
"Reprocessing Date","Patient Name","Dialyzer(Manufacturer,Size)","No.of Reuse","Verification" and
"DialyzerID".
However the problem i am facing is after execution and opening of document is my
column headers in table in pdf report from
c# and datas in it all appear in bold.
I have browsed through net regarding to solve this problem but with no success.
What i want is my pdf report from c# should be similar to following format which i was able to accomplish in vb6,adodb with MS access using iTextSharp.:
Given below is report which i have achieved from vb6,adodb with MS access using iTextSharp
I know that there has to be another way to solve my problem.I have browsed many articles in net regarding exporting sql datas to above format but with no success!
Is there is any another way to solve to my problem on exporting sql datas from c# windows forms using iTextSharp to above format given in the picture/image above?!
If so Then Can anyone tell me what modifications must i do in my c# code given above so that my pdf report from c# windows forms using iTextSharp will look similar to image/picture(pdf report) which i was able to accomplish from
vb6,adodb with ms access using iTextSharp?
I have approached Sound Forge.Net for help but with no success.
I hope anyone/someone truly understands what i am trying to ask!
I know i have to do lot of modifications in my c# code to achieve this level of perfection but i dont know how to do it.
Can anyone help me please! Any help/guidance in solving this problem would be greatly appreciated.
I hope i get a reply in terms of solving this problem.
vishal

Hi,
About iTextSharp component issue , I think this case is off-topic in here.
I suggest you consulting to compenent provider.
http://sourceforge.net/projects/itextsharp/
Regards,
Marvin
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URGENT can anyone let me know how to include sort buttons in table maintian

hi
can anyone let me know how to include sort buttons in table maintianence
as generally table maintianec done have sort buttons i need to include the sort buttons kindly let me know on that asap
or can we use module pool in between table maintianece screen
if yes how touse and how to cod for that
regards
Arora

You can change the coding of Table Maintenance.
>> Goto SM30, give table name and goto Display/Maintain mode and copy all the GUI status from standard program into your function group. Add sort button in the GUI Status of Maintain & Display mode.
>> Goto to tablemaintenance screen generated using SE51.
>> Select change mode.
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How to make a column in Table popin read only

Hi Everyone
Could anyone let me know how to make a column in table popin read only.
Regards

if you ar eusing an ALV table
try this
DATA: lr_salv_wd_table TYPE REF TO iwci_salv_wd_table,
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* get reference to ALV component interface
lr_salv_wd_table = wd_this->wd_cpifc_alvmain( ).
* get ConfigurationModel from ALV Component
wd_this->r_table = lr_salv_wd_table->get_model( ).
* init ColumnSettings
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lr_column_settings ?= wd_this->r_table.
* get table of column settings - each line one column
DATA: lt_columns TYPE salv_wd_t_column_ref.
lt_columns = lr_column_settings->get_columns( ).
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DATA: ls_column TYPE salv_wd_s_column_ref.
* define visible columns (fields) by naming them,
* exclude others by setting visibility to none
DATA: ls_tooltip TYPE string.
LOOP AT lt_columns INTO ls_column.
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ENDLOOP.
Or see this document for more tips.
<a href="https://www.sdn.sap.comhttp://www.sdn.sap.comhttp://www.sdn.sap.com/irj/sdn/go/portal/prtroot/docs/library/uuid/40794172-b95a-2910-fb98-b86d8a0918b4">https://www.sdn.sap.comhttp://www.sdn.sap.comhttp://www.sdn.sap.com/irj/sdn/go/portal/prtroot/docs/library/uuid/40794172-b95a-2910-fb98-b86d8a0918b4</a>
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How to make records to the table TRFCQIN

hi all,
anyone can tell me
how to make records to the table TRFCQIN
regards

Hi Wanna,
Write a module pool program to enter record into table TRFCQIN.
Take fields to which u want to make entries in module pool.
Use insert command to append data in table TRFCQIN.
Refer this code :
CASE OK_CODE_101.
WHEN 'SAV1'.
TRFCQIN-QNAME = 'XYZ'.
TRFCQIN-QCOUNT = "Screen field name at which user will enter value
INSERT TRFCQIN.
if sy-subrc <> 0.
message e007.
else.
clear TRFCQIN.
clear ok_code_101.
endif.
endcase.
Reward points if helpful.
Regards,
Heamnt

What is the difference between standard,sorted and hash table

<b>can anyone say what is the difference between standard,sorted and hash tabl</b>

Hi,
Standard Tables:
Standard tables have a linear index. You can access them using either the index or the key. If you use the key, the response time is in linear relationship to the number of table entries. The key of a standard table is always non-unique, and you may not include any specification for the uniqueness in the table definition.
This table type is particularly appropriate if you want to address individual table entries using the index. This is the quickest way to access table entries. To fill a standard table, append lines using the (APPEND) statement. You should read, modify and delete lines by referring to the index (INDEX option with the relevant ABAP command). The response time for accessing a standard table is in linear relation to the number of table entries. If you need to use key access, standard tables are appropriate if you can fill and process the table in separate steps. For example, you can fill a standard table by appending records and then sort it. If you then use key access with the binary search option (BINARY), the response time is in logarithmic relation to
the number of table entries.
Sorted Tables:
Sorted tables are always saved correctly sorted by key. They also have a linear key, and, like standard tables, you can access them using either the table index or the key. When you use the key, the response time is in logarithmic relationship to the number of table entries, since the system uses a binary search. The key of a sorted table can be either unique, or non-unique, and you must specify either UNIQUE or NON-UNIQUE in the table definition. Standard tables and sorted tables both belong to the generic group index tables.
This table type is particularly suitable if you want the table to be sorted while you are still adding entries to it. You fill the table using the (INSERT) statement, according to the sort sequence defined in the table key. Table entries that do not fit are recognised before they are inserted. The response time for access using the key is in logarithmic relation to the number of
table entries, since the system automatically uses a binary search. Sorted tables are appropriate for partially sequential processing in a LOOP, as long as the WHERE condition contains the beginning of the table key.
Hashed Tables:
Hashes tables have no internal linear index. You can only access hashed tables by specifying the key. The response time is constant, regardless of the number of table entries, since the search uses a hash algorithm. The key of a hashed table must be unique, and you must specify UNIQUE in the table definition.
This table type is particularly suitable if you want mainly to use key access for table entries. You cannot access hashed tables using the index. When you use key access, the response time remains constant, regardless of the number of table entries. As with database tables, the key of a hashed table is always unique. Hashed tables are therefore a useful way of constructing and
using internal tables that are similar to database tables.
Regards,
Ferry Lianto

Sorted and hashed tables

what happens when duplicate entries are present in sorted and hashed tables?

Hi,
Sorted internal tables can be of two types:
unique or non unique.
If u enter duplicate records in Sorted tables with unique it will show error.
If u enter duplicate records in Sorted tables with non-unique key it will not show error.
Hashed tables are with only unique key
so no way to enter the duplicate records.
for more information see the following link
http://help.sap.com/saphelp_nw70/helpdata/en/fc/eb35de358411d1829f0000e829fbfe/content.htm
Reward if helpful.
Jagadish

Hash Table efficiency question

Hi experts,
In my program, I want to read in a lot of string and store the occurance of each string. I found that hash table is the best and most efficient option, but the problem is that, hash table only store one item.
So, I either have to:
1) store an array object into each hash table entries. ie String[String][Occurance]
2) create two hash table based on the hash code of the string.
For 2) I am planning to store all distinct String into one hashtable using the string as the hashcode, then create another hashtable to store the occurance using the String as the hashcode.
My question is that:
1)which implementation is more efficient? Constantly creating String array for each entry or create two hashtables?
2) Is the second implementation possible? Would the hashcode be mapped to different cell in the hashtable even the two hashtable are using the same hashcode and the same size?
Thank you very much for your help.
Kevin

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If you really wanna store another reference for that string, create a simple object
public final class WordCount {
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   * @since 1.1
private String _word;
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   * @since 1.1
private int _count;
   * Creates a new instance of the Word Count Object.
   * @param word The Word being counted.
   * @since 1.1
public WordCount(final String word) {
    super();
    _word = word;
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   * Call this method to increment the Count for the Word.
   * @since 1.1
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   * Retrieves the word being counted.
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   * @since 1.1
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   * Return the Count for the Word.
   * @return Non-negative count for the Word.
   * @since 1.1
public int getCount() {
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}Then your method can be as follows
* Counts the Number of Occurrences of Words within the String
* @param someString The String to be counted for
* @param pattern Pattern to be used to split the String
* @since 1.1
public static final WordCount[] countWords(final String someString, final String pattern) {
StringTokenizer st = new StringTokenizer(someString, pattern);
HashMap wordCountMap = new HashMap();
while (st.hasMoreTokens()) {
    String token = st.nextToken();
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      ((WordCount) wordCountMap.get(token)).increment();
    } else {
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Collection values = wordCountMap.values();
return (WordCount[]) values.toArray(new WordCount[values.size()]);
}Now you can create your own comparator classes to sort the entire array of Word Count Objects. I hope that helps
Regards
Jega

How to get values from Hash Table

Hi all,
I have a hash table "lovResults" craeted with following code -
String lovInputSourceId = pageContext.getParameter(SOURCE_PARAM);
Hashtable lovResults = pageContext.getLovResultsFromSession(lovInputSourceId);
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Hi Amit ,
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Keerthi
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How to make entry in a table e.g. vbak table

how make entries in a table.
what is the procedure.
can i do it in production directly?

>
Vijay Babu Dudla wrote:
> it is not possible to do it directly in production. if you do that you will loose your job, don't practice those on production.
More than loosing you job you are violating the contractual terms with SAP. You will simply loose all Support from SAP.
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Hi
i need to dispaly to dispaly data matrix and table . but matrix data on first page and table data on second page.
how to achive this . if i give pagebreak for every new instance for matrix, only matrix data is getting dispalyed in one page and on the second page seocond record date is getting displayed. after all matrix data is displayed ( in separate pages) , table
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OK. you have your hash table. What you want it to do is keep key/value pairs in linked lists, so that when there is a collision, you add the key/value pair to the linked list rather than searching for free space on the table.
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