Introduction to the advanced function and extension of the JXLS Reader framework
JXLS Reader is a Java framework that is used to analyze the Excel file and provide the function of reading data.It is an extension of the Apache Poi library that provides some advanced functions and extension options to facilitate developers to be more flexible and efficient when processing Excel files.
Here are some advanced functions and extensions of the JXLS Reader framework:
1. Table read: JXLS Reader supports the data in Excel files in the form of a table.According to the definition of the template file, it maps the data in Excel into the Java object and simplifies the process of data reading.Developers can specify the mapping relationship of the data position and target Java object attributes to be read by configure the template file.
The following is an example. Demonstrate how to use JXLS Reader to read the data in Excel to the Java object:
try (InputStream is = new FileInputStream("input.xls")) {
JxlsReader reader = new JxlsReader();
List<MyObject> objects = reader.read(is, MyObject.class);
for (MyObject obj : objects) {
// Do something with obj
System.out.println(obj.getName());
}
} catch (IOException e) {
e.printStackTrace();
}
2. Dynamic table: JXLS Reader supports the reading of the dynamic table, that is, the data range to be read is determined based on the layout in Excel.This is very useful for processing the Excel file with variable columns and rows.Developers only need to specify the position of the data start, and JXLS Reader will automatically expand the range to read all data.
The following is an example to display the data of how to read the dynamic table:
try (InputStream is = new FileInputStream("input.xls")) {
JxlsReader reader = new JxlsReader();
List<List<Object>> data = reader.readDynamicTable(is, 1, 1);
for (List<Object> row : data) {
for (Object cellValue : row) {
// Do something with cellValue
System.out.println(cellValue);
}
}
} catch (IOException e) {
e.printStackTrace();
}
3. Custom converter: JXLS Reader supports custom converter, allowing developers to customize the conversion operation of read data according to business needs.Developers can implement the Converter interface and register it into the JXLS Reader for the corresponding conversion when reading data.
The following is an example, how to register and use a custom converter for demonstration:
public class MyConverter implements Converter {
@Override
public Object convert(Object value) throws ParseException {
// Custom conversion logic
return value.toString().toUpperCase();
}
}
try (InputStream is = new FileInputStream("input.xls")) {
JxlsReader reader = new JxlsReader();
reader.registerConverter(String.class, new MyConverter());
List<MyObject> objects = reader.read(is, MyObject.class);
for (MyObject obj : objects) {
// Do something with obj
System.out.println(obj.getName());
}
} catch (IOException e) {
e.printStackTrace();
}
Summarize:
The JXLS Reader framework provides many advanced functions and extensions to simplify the process of Excel data reading.Read data in the form of tables, support dynamic table reading, and use a custom converter to convert the read data.These functions enable developers to process data in Excel files more flexible and efficiently.
