http://www.dropwizard.io/2.0.18/dropwizard-bom/dropwizard-dependencies/dropwizard-parent/dropwizard-validation: Dropwizard is a Java framework for developing ops-friendly, high-performance, RESTful web applications.
  • Coda Hale
  • Nick Telford
  • Graham O'Regan
  • Ryan Kennedy
  • Camille Fournier
  • Carlo Barbara
  • Matt Veitas
  • Ryan Tenney
  • Jochen Schalanda
  • Glenn McAllister
  • Nick Babcock
  • Justin Plock
  • Artem Prigoda 
package io.dropwizard.validation;

import io.dropwizard.util.Size;
import io.dropwizard.util.SizeUnit;

import javax.validation.ConstraintValidator;
import javax.validation.ConstraintValidatorContext;


Check that a Size being validated is greater than or equal to the minimum value specified. 
/**
 * Check that a {@link Size} being validated is greater than or equal to the
 * minimum value specified.
 */
public class MinSizeValidator implements ConstraintValidator<MinSize, Size> {

    private long minQty = 0;
    private SizeUnit minUnit = SizeUnit.BYTES;

    @Override
    public void initialize(MinSize constraintAnnotation) {
        this.minQty = constraintAnnotation.value();
        this.minUnit = constraintAnnotation.unit();
    }

    @Override
    public boolean isValid(Size value, ConstraintValidatorContext context) {
        return (value == null) || (value.toBytes() >= minUnit.toBytes(minQty));
    }
}