The core technical principles of the CLJ Excel framework in the Java class library

The core technical principle of the CLJ Excel framework in the Java class library The CLJ Excel framework is a powerful Java class library that is used to handle the reading and writing of the Excel file.It is based on Java's Apache Poi library and provides more concise API and more efficient performance.This article will introduce the core technical principles of the CLJ Excel framework, including the processing of workbooks, workheets (sheets), cells, and formula. 1. Workbook (Workbook): The CLJ Excel framework uses the workbook object to represent the excel file, which is the entrance to all operations.The workbook can be initialized by reading the existing Excel file or creating a new Excel file. The following is a sample code for creating a new workbook: Workbook workbook = Excel.createWorkbook(); Or you can initialize by reading the existing Excel file: Workbook workbook = Excel.readFile("path/to/excel.xls"); 2. SHEET: The CLJ Excel framework uses Sheet objects to represent the worksheet in Excel file.The worksheet can be accessed by indexes or names.In the worksheet, you can perform operations (ROW) and Column. The following is a sample code for creating a new worksheet in the workbook: Sheet sheet = workbook.createSheet("Sheet1"); Or you can obtain the worksheet through the index: Sheet sheet = workbook.getSheet(0); 3. CELL: The CLJ Excel framework uses cell objects to represent the cell in the excel file.The cell can be accessed through the indexes of lines and columns.You can set and obtain attributes such as values, styles and formulas of cells. Here are examples of setting and obtaining the unit value of the unit: Cell cell = sheet.getCell(0, 0); cell.setValue("Hello, World!"); String value = cell.getValue(); You can use different data types to set the value of the cell, such as string, numbers, and dates. 4. Official (formula): The CLJ Excel framework supports the formula in the cell.It can be achieved by setting the formula attributes of the cell.The formula can quote other cells and have a variety of built -in functions for calculation. The following is a sample code for setting the cell formula: Cell cell = sheet.getCell(1, 0); cell.setFormula("SUM(A1:A3)"); String formula = cell.getFormula(); The formula of the cell will automatically value when calculating, and the results are displayed in the corresponding cell. Summarize: The CLJ Excel framework is a powerful Java class library, which provides a more concise and efficient API based on the Apache Poi library.This article introduces the core technical principles of the CLJ Excel framework, including the processing of workbooks, worksheets, cells and formulas.By using these core technologies, you can easily read and write with Excel files, and perform various operations and calculations.Regardless of whether you are processing data, reporting, or other Excel -related tasks, the CLJ Excel framework is a choice worth trying.