EmailAddress.java

package com.oreilly.springdata.jdbc.domain;

import org.springframework.util.Assert;

import java.util.regex.Pattern;

/**
 */
public class EmailAddress {

	private static final String EMAIL_REGEX = "^[_A-Za-z0-9-]+(\\.[_A-Za-z0-9-]+)*@[A-Za-z0-9]+(\\.[A-Za-z0-9]+)*(\\.[A-Za-z]{2,})$";
	private static final Pattern PATTERN = Pattern.compile(EMAIL_REGEX);

	private String value;

	protected EmailAddress() {
	}

	public EmailAddress(String emailAddress) {
		Assert.isTrue(isValid(emailAddress), "Invalid email address!");
		this.value = emailAddress;
	}

	public static boolean isValid(String candidate) {
		return candidate == null ? false : PATTERN.matcher(candidate).matches();
	}

	@Override
	public boolean equals(Object o) {
		if (this == o) return true;
		if (o == null || getClass() != o.getClass()) return false;

		EmailAddress that = (EmailAddress) o;

		if (value != null ? !value.equals(that.value) : that.value != null) return false;

		return true;
	}

	@Override
	public int hashCode() {
		return value != null ? value.hashCode() : 0;
	}

	@Override
	public String toString() {
		return value;
	}
}