using commons-validator for email address validation

Author: erosb

core/pom.xml

@@ -91,6 +91,11 @@
       <version>4.12</version>
       <scope>test</scope>
     </dependency>
+    <dependency>
+      <groupId>commons-validator</groupId>
+      <artifactId>commons-validator</artifactId>
+      <version>1.5.0</version>
+    </dependency>
     <dependency>
       <groupId>org.mockito</groupId>
       <artifactId>mockito-core</artifactId>

core/src/main/java/org/everit/json/schema/internal/DefaultFormatValidator.java

@@ -8,6 +8,7 @@
 import java.util.Objects;
 import java.util.Optional;
 
+import org.apache.commons.validator.routines.EmailValidator;
 import org.everit.json.schema.Format;
 import org.everit.json.schema.FormatValidator;
 
@@ -50,6 +51,13 @@ private Optional<String> checkDateTime(final String subject) {
     }
   }
 
+  private Optional<String> checkEmail(final String subject) {
+    if (EmailValidator.getInstance(false, true).isValid(subject)) {
+      return Optional.empty();
+    }
+    return Optional.of(String.format("[%s] is not a valid email address", subject));
+  }
+
   private Optional<String> checkHostname(final String subject) {
     try {
       InternetDomainName.from(subject);
@@ -90,6 +98,8 @@ public Optional<String> validate(final String subject, final Format format) {
         return checkURI(subject);
       case DATE_TIME:
         return checkDateTime(subject);
+      case EMAIL:
+        return checkEmail(subject);
       default:
         throw new IllegalArgumentException("unsupported format: " + format);
     }

core/src/test/java/org/everit/json/schema/internal/DefaultFormatValidatorTest.java

@@ -2,6 +2,7 @@
 
 import java.util.Optional;
 
+import org.apache.commons.validator.routines.EmailValidator;
 import org.everit.json.schema.Format;
 import org.junit.Assert;
 import org.junit.Test;
@@ -46,6 +47,18 @@ public void dateTimeZSuccess() {
     assertSuccess("2015-02-30T11:00:00Z", Format.DATE_TIME);
   }
 
+  @Test
+  public void emailFailure() {
+    assertFailure("[email protected]", Format.EMAIL, "[[email protected]] is not a valid email address");
+  }
+
+  @Test
+  public void emailSuccess() {
+    assertSuccess("[email protected]", Format.EMAIL);
+    Assert.assertTrue(EmailValidator.getInstance().isValid("[email protected]"));
+    Assert.assertFalse(EmailValidator.getInstance().isValid("[email protected]"));
+  }
+
   @Test
   public void hostnameLengthFailure() {
     StringBuilder sb = new StringBuilder();