Detailed method of using Genjava CSV framework in the Java library detailed explanation
Detailed method of using Genjava CSV framework in the Java library detailed explanation
CSV (comma division value) is a common file format that stores and exchange simple data tables.In Java development, processing CSV files is one of the common tasks.Genjava is an open source Java class library that provides the function of processing CSV files and simplifies the reading and writing operation of CSV files.This article will introduce the use of the Genjava CSV framework in the Java class library in detail, and provide the corresponding Java code example.
## 1. Genjava CSV Introduction
Genjava CSV is an open source Java class library that provides rich functions to process CSV files.It has the characteristics of high performance, ease of use and flexibility.Genjava CSV can help developers simplify the interaction with CSV files and provide a series of APIs for reading and writing CSV files.
## 2. Genjava CSV installation
To use the Genjava CSV in the Java project, you need to add it to the dependence of the project.Can be installed and configured by adding jar files by Maven or manually.The following are examples of adding Genjava CSV dependency items with Maven:
<dependency>
<groupId>com.genjava</groupId>
<artifactId>genjava-csv</artifactId>
<version>1.0.0</version>
</dependency>
## 3. Read csv file
It is very simple to read the CSV file with Genjava CSV.First, you need to create a CSVReader object and specify the path of the CSV file to be read.You can then read the contents of the CSV file with the method of the CSVReader object.
The following is an example of reading CSV files:
import com.genjava.csv.CSVReader;
public class CSVReaderExample {
public static void main(String[] args) {
try {
CSVReader csvReader = new CSVReader("path/to/csv/file.csv");
String[] row;
while ((row = csvReader.readNextRow()) != null) {
for (String cell : row) {
System.out.print(cell + ", ");
}
System.out.println();
}
csvReader.close();
} catch (Exception e) {
e.printStackTrace();
}
}
}
In the above example, first create a CSVReader object, and then read the content of the CSV file by calling the method by calling `ReadnextRow ()` and store the data of each line in a string array.Then traverse the array and print the value of each cell.Finally, call the `Close () method to close the CSVReader object.
## 4. Write into CSV files
It is also very simple to write data to the CSV file with Genjava CSV.First of all, you need to create a CSVWriter object and specify the path of the CSV file to be written.You can then write the data into the CSV file by using the CSVWriter object.
The following is an example of a CSV file:
import com.genjava.csv.CSVWriter;
public class CSVWriterExample {
public static void main(String[] args) {
try {
CSVWriter csvWriter = new CSVWriter("path/to/csv/file.csv");
String[] row1 = {"John", "Doe", "john.doe@example.com"};
String[] row2 = {"Jane", "Smith", "jane.smith@example.com"};
csvWriter.writeNextRow(row1);
csvWriter.writeNextRow(row2);
csvWriter.close();
} catch (Exception e) {
e.printStackTrace();
}
}
}
In the above example, first create a CSVWriter object, and then write the data to the CSV file by calling the method by calling the method by calling `` `` `` `` `` `` `` `` `` `` `` `` `` `` `` `` `` `` `` `` `` `sayNenextrow (method.Each data row is expressed as a string array.Finally, call the `Close ()" method to close the CSVWRiter object.
## 5. Genjava CSV advanced function
In addition to basic reading and writing operations, Genjava CSV also provides other functions that can further customize and control the processing process of CSV files.Here are some common advanced functions:
-Set the field separation symbol: Set the field separation symbol by calling the method by calling the `SetDelimiter ()` method, the default is the comma.
-Set the text packaging: You can set the text packaging symbol by calling the method by calling the method of calling `setquotechar ()`, and the default is dual quotation marks.
-Admail: You can set whether to ignore the empty line by calling the method settings by calling `setskipemptyrows ()` `` `). The default is false.
-S selective reading/Writing column: You can selectively read or write a specific column by setting a column number or column name.
The above are just examples of some common functions. Genjava CSV also provides some other advanced functions, such as processing large CSV files and processing CSV files containing nested structures.
In summary, the Genjava CSV framework is a powerful and easy -to -use Java class library that can be used to read and write CSV files.By using Genjava CSV, developers can simplify interaction with CSV files and easily process CSV data.It is hoped that the detailed methods and examples provided in this article can help readers better understand and use the Genjava CSV framework.
