How to access a value defined in the application.properties file in Spring Boot

You can use the @Value annotation and access the property in whichever Spring bean you're using

@Value("${userBucket.path}")
private String userBucketPath;

The Externalized Configuration section of the Spring Boot docs, explains all the details that you might need.

Another way is injecting org.springframework.core.env.Environment to your bean.

@Autowired
private Environment env;
....

public void method() {
    .....  
    String path = env.getProperty("userBucket.path");
    .....
}

@ConfigurationProperties can be used to map values from .properties( .yml also supported) to a POJO.

Consider the following Example file.

.properties

cust.data.employee.name=Sachin
cust.data.employee.dept=Cricket

Employee.java

import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Configuration;

@ConfigurationProperties(prefix = "cust.data.employee")
@Configuration("employeeProperties")
public class Employee {

    private String name;
    private String dept;

    //Getters and Setters go here
}

Now the properties value can be accessed by autowiring employeeProperties as follows.

@Autowired
private Employee employeeProperties;

public void method() {

   String employeeName = employeeProperties.getName();
   String employeeDept = employeeProperties.getDept();

}