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package org.apache.poi.xssf.model;
import org.apache.poi.ss.usermodel.RichTextString;
/**
* Table of strings shared across all sheets in a workbook.
*
* A workbook may contain thousands of cells containing string (non-numeric) data. Furthermore this data is very
* likely to be repeated across many rows or columns. The goal of implementing a single string table that is shared
* across the workbook is to improve performance in opening and saving the file by only reading and writing the
* repetitive information once.
*
*
* Consider for example a workbook summarizing information for cities within various countries. There may be a
* column for the name of the country, a column for the name of each city in that country, and a column
* containing the data for each city. In this case the country name is repetitive, being duplicated in many cells.
* In many cases the repetition is extensive, and a tremendous savings is realized by making use of a shared string
* table when saving the workbook. When displaying text in the spreadsheet, the cell table will just contain an
* index into the string table as the value of a cell, instead of the full string.
*
*
* The shared string table contains all the necessary information for displaying the string: the text, formatting
* properties, and phonetic properties (for East Asian languages).
*
*/
public interface SharedStrings {
/**
* Return a string item by index
*
* @param idx index of item to return.
* @return the item at the specified position in this Shared String table.
*/
RichTextString getItemAt(int idx);
/**
* Return an integer representing the total count of strings in the workbook. This count does not
* include any numbers, it counts only the total of text strings in the workbook.
*
* @return the total count of strings in the workbook
*/
int getCount();
/**
* Returns an integer representing the total count of unique strings in the Shared String Table.
* A string is unique even if it is a copy of another string, but has different formatting applied
* at the character level.
*
* @return the total count of unique strings in the workbook
*/
int getUniqueCount();
}