package org.apache.wicket.bean.validation;

import javax.validation.constraints.Size;

import org.apache.wicket.markup.ComponentTag;
import org.apache.wicket.markup.html.form.FormComponent;

/**
 * A tag modifier that adds the {@code maxlength} and  {@code minlength} attributes to the {@code input}
 * and {@code textarea} tag with the max/min value from the {@link Size} constraint annotation.
 * 
 * @author igor
 * 
 */
public class SizeTagModifier implements ITagModifier<Size>
{
	@Override
	public void modify(FormComponent<?> component, ComponentTag tag, Size annotation)
	{
		if (hasLengthAttribute(tag.getName()))
		{
			tag.put("maxlength", annotation.max());

			if (annotation.min() > 0)
			{
				tag.put("minlength", annotation.min());
			}
		}
	}

	protected boolean hasLengthAttribute(String tagName)
	{
		return "input".equalsIgnoreCase(tagName) || "textarea".equalsIgnoreCase(tagName);
	}
}

package org.apache.wicket.bean.validation;

import javax.validation.constraints.Size;

import org.apache.wicket.markup.ComponentTag;
import org.apache.wicket.markup.html.form.FormComponent;

/**
 * A tag modifier that adds the {@code maxlength} attribute to the {@code input} tag with the max
 * value from the {@link Size} constraint annotation.
 * 
 * @author igor
 * 
 */
public class SizeTagModifier implements ITagModifier<Size>
{
	@Override
	public void modify(FormComponent<?> component, ComponentTag tag, Size annotation)
	{
		if ("input".equalsIgnoreCase(tag.getName()))
		{
			tag.put("maxlength", annotation.max());
		}
	}
}

--- 
+++ 
@@ -6,8 +6,8 @@
 import org.apache.wicket.markup.html.form.FormComponent;
 
 /**
- * A tag modifier that adds the {@code maxlength} attribute to the {@code input} tag with the max
- * value from the {@link Size} constraint annotation.
+ * A tag modifier that adds the {@code maxlength} and  {@code minlength} attributes to the {@code input}
+ * and {@code textarea} tag with the max/min value from the {@link Size} constraint annotation.
  * 
  * @author igor
  * 
@@ -17,9 +17,19 @@
 	@Override
 	public void modify(FormComponent<?> component, ComponentTag tag, Size annotation)
 	{
-		if ("input".equalsIgnoreCase(tag.getName()))
+		if (hasLengthAttribute(tag.getName()))
 		{
 			tag.put("maxlength", annotation.max());
+
+			if (annotation.min() > 0)
+			{
+				tag.put("minlength", annotation.min());
+			}
 		}
 	}
+
+	protected boolean hasLengthAttribute(String tagName)
+	{
+		return "input".equalsIgnoreCase(tagName) || "textarea".equalsIgnoreCase(tagName);
+	}
 }
Add 'minlength' to <input> or <textarea> if Size.min() is bigger than 0

Fixes #144
