Purecsv framework example: How to use the Java class library to analyze CSV files
Purecsv framework example: How to use the Java class library to analyze CSV files
introduce:
CSV (comma segmental value) is a commonly used data format that is widely used in many applications.In Java, many types of libraries can help us analyze and process CSV files.PURECSV is one of the simple and easy -to -use Java libraries. This article will introduce how to use the PureCSV framework to resolve the CSV file.
PURECSV is an open source Java class library that provides a simple API to read and write CSV files.It has excellent performance and flexible functions, and can adapt to a variety of different CSV formats.
Step 1: Add PureCSV dependencies
First, we need to add the dependencies of Purecsv to the project.In the pom.xml file, add the following dependent configuration:
<dependency>
<groupId>com.googlecode.jcsv</groupId>
<artifactId>javacsv</artifactId>
<version>2.0</version>
</dependency>
Step 2: Create CSV files
Before analyzing the CSV file, we need to create a CSV file of an example.You can use any text editor to create a file with a comma (or other separators) separate fields, such as:
Name,Age,City
Alice,28,Shanghai
Bob,35,Beijing
Charlie,42,Guangzhou
Save the file to "example.csv".
Step 3: Analyze CSV files
Now, we will show how to use the PureCSV library to analyze the CSV file created in the previous step.
First of all, we need to create a Pojo class class to represent the data row in the CSV file.In this example, we create a class called "Person", which has names, age, and urban attributes.
public class Person {
private String name;
private int age;
private String city;
// Construct function, Getter, Setter method, etc.
// Tostring () Method for printing object information
@Override
public String toString() {
return "Person [name=" + name + ", age=" + age + ", city=" + city + "]";
}
}
Next, we use PureCSV to parse the CSV file and map each row of data to the Person object.
import com.googlecode.jcsv.CSVStrategy;
import com.googlecode.jcsv.reader.CSVReader;
import com.googlecode.jcsv.reader.internal.CSVReaderBuilder;
import java.io.FileReader;
import java.io.IOException;
import java.util.List;
public class CSVParserExample {
public static void main(String[] args) throws IOException {
String csvFile = "example.csv";
CSVReader<Person> csvReader = new CSVReaderBuilder<Person>(new FileReader(csvFile))
.strategy(CSVStrategy.UK_DEFAULT)
.entryParser(new BeanEntryParser<Person>(Person.class))
.build();
List<Person> persons = csvReader.readAll();
for (Person person : persons) {
System.out.println(person);
}
csvReader.close();
}
}
In the above code, we first create a CSVReader object and pass the reader and analytical strategy of the CSV file.Then, we read all the data rows through the method of `Readall ()` and map each row of data to the Person object.
Finally, we traverse the Person object list and print the information of each object.
Step 4: Running program
Now, we can run the above code to analyze the "Example.csv" file.After running the program, the output will print the information of each person object.
Person [name=Alice, age=28, city=Shanghai]
Person [name=Bob, age=35, city=Beijing]
Person [name=Charlie, age=42, city=Guangzhou]
The above is the example code of the PureCSV framework to resolve the CSV file.PURECSV provides a simple, flexible and efficient way to handle CSV files.Through the introduction of this article, I believe you have learned how to use the PureCSV framework to analyze the CSV file.
