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    <title>DEV Community: Dave Brown</title>
    <description>The latest articles on DEV Community by Dave Brown (@dave_brown_46fcbc7803d26f).</description>
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      <title>DEV Community: Dave Brown</title>
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    <item>
      <title>Spring Boot Validation Groups</title>
      <dc:creator>Dave Brown</dc:creator>
      <pubDate>Wed, 18 Mar 2026 12:59:47 +0000</pubDate>
      <link>https://dev.to/dave_brown_46fcbc7803d26f/spring-boot-validation-groups-5ged</link>
      <guid>https://dev.to/dave_brown_46fcbc7803d26f/spring-boot-validation-groups-5ged</guid>
      <description>&lt;p&gt;If you've ever written nearly-identical CreateRequest and UpdateRequest DTOs just because the validation rules differ (ID must be null on create, required on update), there's a better way.&lt;/p&gt;

&lt;p&gt;Spring Boot's Validation Groups let you define different constraint profiles on a single DTO and activate the right one per endpoint.&lt;/p&gt;

&lt;p&gt;The setup:&lt;br&gt;
&lt;/p&gt;

&lt;div class="highlight js-code-highlight"&gt;
&lt;pre class="highlight java"&gt;&lt;code&gt;&lt;span class="kd"&gt;public&lt;/span&gt; &lt;span class="kd"&gt;interface&lt;/span&gt; &lt;span class="nc"&gt;OnCreate&lt;/span&gt; &lt;span class="o"&gt;{}&lt;/span&gt;
&lt;span class="kd"&gt;public&lt;/span&gt; &lt;span class="kd"&gt;interface&lt;/span&gt; &lt;span class="nc"&gt;OnUpdate&lt;/span&gt; &lt;span class="o"&gt;{}&lt;/span&gt;

&lt;span class="kd"&gt;public&lt;/span&gt; &lt;span class="kd"&gt;class&lt;/span&gt; &lt;span class="nc"&gt;UserRequest&lt;/span&gt; &lt;span class="o"&gt;{&lt;/span&gt;
    &lt;span class="nd"&gt;@Null&lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="n"&gt;groups&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="nc"&gt;OnCreate&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="na"&gt;class&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;
    &lt;span class="nd"&gt;@NotNull&lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="n"&gt;groups&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="nc"&gt;OnUpdate&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="na"&gt;class&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;
    &lt;span class="kd"&gt;private&lt;/span&gt; &lt;span class="nc"&gt;Long&lt;/span&gt; &lt;span class="n"&gt;id&lt;/span&gt;&lt;span class="o"&gt;;&lt;/span&gt;

    &lt;span class="nd"&gt;@NotBlank&lt;/span&gt;
    &lt;span class="kd"&gt;private&lt;/span&gt; &lt;span class="nc"&gt;String&lt;/span&gt; &lt;span class="n"&gt;name&lt;/span&gt;&lt;span class="o"&gt;;&lt;/span&gt;
&lt;span class="o"&gt;}&lt;/span&gt;
&lt;/code&gt;&lt;/pre&gt;

&lt;/div&gt;



&lt;p&gt;In your controller, swap &lt;a class="mentioned-user" href="https://dev.to/valid"&gt;@valid&lt;/a&gt; for @Validated with the group:&lt;br&gt;
&lt;/p&gt;

&lt;div class="highlight js-code-highlight"&gt;
&lt;pre class="highlight java"&gt;&lt;code&gt;&lt;span class="nd"&gt;@PostMapping&lt;/span&gt;
&lt;span class="kd"&gt;public&lt;/span&gt; &lt;span class="nc"&gt;ResponseEntity&lt;/span&gt;&lt;span class="o"&gt;&amp;lt;?&amp;gt;&lt;/span&gt; &lt;span class="n"&gt;create&lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="nd"&gt;@Validated&lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="nc"&gt;OnCreate&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="na"&gt;class&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt; &lt;span class="nd"&gt;@RequestBody&lt;/span&gt; &lt;span class="nc"&gt;UserRequest&lt;/span&gt; &lt;span class="n"&gt;req&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt; &lt;span class="o"&gt;{&lt;/span&gt; &lt;span class="o"&gt;...&lt;/span&gt; &lt;span class="o"&gt;}&lt;/span&gt;

&lt;span class="nd"&gt;@PutMapping&lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="s"&gt;"/{id}"&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;
&lt;span class="kd"&gt;public&lt;/span&gt; &lt;span class="nc"&gt;ResponseEntity&lt;/span&gt;&lt;span class="o"&gt;&amp;lt;?&amp;gt;&lt;/span&gt; &lt;span class="n"&gt;update&lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="nd"&gt;@Validated&lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="nc"&gt;OnUpdate&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="na"&gt;class&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt; &lt;span class="nd"&gt;@RequestBody&lt;/span&gt; &lt;span class="nc"&gt;UserRequest&lt;/span&gt; &lt;span class="n"&gt;req&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt; &lt;span class="o"&gt;{&lt;/span&gt; &lt;span class="o"&gt;...&lt;/span&gt; &lt;span class="o"&gt;}&lt;/span&gt;
&lt;/code&gt;&lt;/pre&gt;

&lt;/div&gt;



&lt;p&gt;Spring applies only the constraints matching the group you specify. Constraints with no group annotation apply in both cases.&lt;/p&gt;

&lt;p&gt;This scales well for lifecycle-based rules — fields that are optional on creation but locked down once a record is active, or validation that only applies during specific operations.&lt;/p&gt;

&lt;p&gt;Full article covers this plus custom field-level validators, class-level multi-field constraints, and service-layer validation: &lt;a href="https://tucanoo.com/spring-boot-input-validation-complete-guide/" rel="noopener noreferrer"&gt;https://tucanoo.com/spring-boot-input-validation-complete-guide/&lt;/a&gt;&lt;/p&gt;

&lt;h1&gt;
  
  
  SpringBoot #Java #APIDesign
&lt;/h1&gt;

</description>
      <category>webdev</category>
      <category>springboot</category>
      <category>java</category>
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