SpringBoot DevTools, Lombok, and Configuration Processor: A Quick Guide for Hot Deployment and Code Simplification

1. SpringBoot DevTools

SpringBoot DevTools is a tool that enables hot deployment for SpringBoot applications. It can be added by checking the option when creating a project or by adding the Maven dependency shown below.

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-devtools</artifactId>
    <optional>true</optional>
</dependency>

In IntelliJ IDEA press Ctrl+F9 after editing code to recompile; Eclipse recompiles automatically on save. To achieve automatic recompilation without manual trigger, enable the following settings in IDEA and modify the pom.xml as illustrated.

Step 1: Enable options in IDEA settings

Step 2: Place cursor after the <build> tag in pom.xml and press Alt+Shift+Ctrl+/

Step 3: Check the required options and restart IDEA

2. Lombok

Lombok simplifies JavaBean development by generating constructors, getters, and setters automatically.

You can enable Lombok by selecting the option during project initialization or by adding the following Maven dependency.

<dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId>
    <optional>true</optional>
</dependency>

IDEA also requires the Lombok plugin, as shown in the screenshot.

Example usage:

import com.baomidou.mybatisplus.annotation.TableField;
import com.baomidou.mybatisplus.annotation.TableName;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

@AllArgsConstructor // all-args constructor
@NoArgsConstructor // no-args constructor
@Data // getter + setter
public class User {
    private Long id;
    private String name;
    private Integer age;
    private String email;
}

3. Spring Configuration Processor

The Spring Configuration Processor provides property‑binding hints for @ConfigurationProperties classes, though its benefit may be limited.

Example entity with @ConfigurationProperties:

package org.lzl.HelloWorld.entity;

import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.stereotype.Component;

@Component
@ConfigurationProperties(prefix = "mypet")
public class Pet {
    private String nickName;
    private String strain;
    // getters and setters omitted for brevity
    @Override
    public String toString() {
        return "Pet [nickName=" + nickName + ", strain=" + strain + "]";
    }
}

To enable property suggestions in application.properties or application.yml , select the appropriate option when creating the SpringBoot project, or add the following Maven dependency and exclude it from the final jar to reduce size.

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-configuration-processor</artifactId>
    <optional>true</optional>
</dependency>

<build>
    <plugins>
        <plugin>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-maven-plugin</artifactId>
            <configuration>
                <excludes>
                    <exclude>
                        <groupId>org.springframework.boot</groupId>
                        <artifactId>spring-boot-configuration-processor</artifactId>
                    </exclude>
                </excludes>
            </configuration>
        </plugin>
    </plugins>
</build>