How Java creates YAML files using the APIs of Jackson, SnapeYAML, or YamlBeans libraries
To create YAML files using the Jackson library, you need to add the following dependencies to your Maven project:
<dependency>
<groupId>com.fasterxml.jackson.dataformat</groupId>
<artifactId>jackson-dataformat-yaml</artifactId>
<version>2.12.5</version>
</dependency>
The following is an example of a YAML file:
yaml
users:
- name: John
age: 25
- name: Jane
age: 30
The example code for creating this YAML file using the Jackson library is as follows:
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.dataformat.yaml.YAMLFactory;
import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
public class Main {
public static void main(String[] args) {
User user1 = new User("John", 25);
User user2 = new User("Jane", 30);
List<User> users = new ArrayList<>();
users.add(user1);
users.add(user2);
UsersWrapper wrapper = new UsersWrapper(users);
ObjectMapper mapper = new ObjectMapper(new YAMLFactory());
try {
mapper.writeValue(new File("path/to/output.yaml"), wrapper);
} catch (IOException e) {
e.printStackTrace();
}
}
static class User {
private String name;
private int age;
public User() {}
public User(String name, int age) {
this.name = name;
this.age = age;
}
// Getters and setters
}
static class UsersWrapper {
@JsonProperty("users")
private List<User> users;
public UsersWrapper() {}
public UsersWrapper(List<User> users) {
this.users = users;
}
// Getters and setters
}
}
To create YAML files using the SnapeYAML library, you need to add the following dependencies to your maven project:
<dependency>
<groupId>org.yaml</groupId>
<artifactId>snakeyaml</artifactId>
<version>1.28</version>
</dependency>
The following is an example of a YAML file (as above).
The example code for creating this YAML file using the SnapeYAML library is as follows:
import org.yaml.snakeyaml.Yaml;
import java.io.FileWriter;
import java.io.IOException;
import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
public class Main {
public static void main(String[] args) {
User user1 = new User("John", 25);
User user2 = new User("Jane", 30);
List<User> users = new ArrayList<>();
users.add(user1);
users.add(user2);
Map<String, List<User>> data = new LinkedHashMap<>();
data.put("users", users);
Yaml yaml = new Yaml();
try {
FileWriter writer = new FileWriter("path/to/output.yaml");
yaml.dump(data, writer);
} catch (IOException e) {
e.printStackTrace();
}
}
static class User {
private String name;
private int age;
public User() {}
public User(String name, int age) {
this.name = name;
this.age = age;
}
// Getters and setters
}
}
To create YAML files using the YamlBeans library, you need to add the following dependencies to your Maven project:
<dependency>
<groupId>com.esotericsoftware</groupId>
<artifactId>yamlbeans</artifactId>
<version>1.14</version>
</dependency>
The following is an example of a YAML file (as above).
The example code for creating this YAML file using the YamlBeans library is as follows:
import com.esotericsoftware.yamlbeans.YamlWriter;
import java.io.FileWriter;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
public class Main {
public static void main(String[] args) {
User user1 = new User("John", 25);
User user2 = new User("Jane", 30);
List<User> users = new ArrayList<>();
users.add(user1);
users.add(user2);
UsersWrapper wrapper = new UsersWrapper(users);
try {
FileWriter writer = new FileWriter("path/to/output.yaml");
YamlWriter yamlWriter = new YamlWriter(writer);
yamlWriter.write(wrapper);
yamlWriter.close();
} catch (IOException e) {
e.printStackTrace();
}
}
static class User {
private String name;
private int age;
public User() {}
public User(String name, int age) {
this.name = name;
this.age = age;
}
// Getters and setters
}
static class UsersWrapper {
private List<User> users;
public UsersWrapper() {}
public UsersWrapper(List<User> users) {
this.users = users;
}
// Getters and setters
}
}
Please replace the 'path/to/output. yaml' in the code with the file path you want to output to.
