Interpretation of the technical principles of Table/IO CSV SUPPORT framework in Java
Table/IO CSV support framework technical principle interpretation
In the Java class library, the Table/IO CSV support framework is a powerful tool to process the CSV (comma separation value) file.This article will explain the technical principles of the framework and how to use it in the Java code to read and write into the CSV file.
Technical principle:
The table/IO CSV support framework is based on Java's TABLE API and IO library, providing high -level and easy -to -use functions to process CSV files.Its main principle is to analyze the CSV file as a Table object of Java, so that the CSV data can be easily stored as a form and processed by table operation.
The important components of this framework include the following aspects:
1. CSV parser (CSV Parser): This module can read and analyze CSV files and convert data to table format.It supports customized separators, quotes characters, and rotary characters to adapt to different CSV file formats.
2. Table Data Structure: Table/IO CSV support framework uses Java's Table data structure to store CSV data.The form is similar to the traditional two -dimensional table, which can contain multi -line and multi -row data, and provides rich operating methods, such as filtering, sorting, and aggregation.
3. Data Writer: This module is responsible for writing the data of the Table object into the CSV file.It supports the form data to write the file according to the specified format, and can be selectively included in the title and quotation marks.
Example:
Below is a sample code that demonstrates how to use Table/IO CSV support framework to read and write CSV files.
import com.google.common.io.Files;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.Lists;
import tech.tablesaw.api.Table;
import tech.tablesaw.io.csv.CsvReadOptions;
import tech.tablesaw.io.csv.CsvWriteOptions;
import tech.tablesaw.io.csv.CsvWriter;
import java.io.File;
import java.io.IOException;
public class CsvExample {
public static void main(String[] args) {
// Read the CSV file
Table table = null;
try {
CsvReadOptions options = CsvReadOptions.builder(new File("data.csv")).build();
table = Table.read().csv(options);
} catch (IOException e) {
e.printStackTrace();
}
// Execute the operation in the table
Table filteredTable = table.where(table.column("Age").isGreaterThan(25));
// Write into CSV files
try {
CsvWriteOptions options = CsvWriteOptions.builder(new File("filtered_data.csv"))
.header(true)
.build();
CsvWriter writer = new CsvWriter();
writer.write(filteredTable, options);
} catch (IOException e) {
e.printStackTrace();
}
}
}
In the above sample code, first specify the CSV file to be read through the `CSVReadoptions` Constructioner, and call the` Table.read (). CSV (Options) method to read it as a Table object.Then, use Table objects for various operations, such as filtering.Finally, use the CSV file to be written with the `CSVWREOPTIONS` Constructioner, and call the` WRITE` method of `csvwriter` to write the form data into the file.
Using Table/IO CSV Support framework, we can easily read and write CSV files and use powerful table operations to process data.It provides a form -based method, simplifies the complexity of handling CSV files, and provides developers with more efficient and convenient ways to process and analyze CSV data.
