Fix #13 - overflow exception

build.gradle

@@ -19,6 +19,7 @@ dependencies {
     testCompile group: 'junit', name: 'junit', version: '4.11'
     testCompile group: 'com.tngtech.java', name: 'junit-dataprovider', version: '1.9.2'
     testCompile "org.mockito:mockito-core:1.+"
+    testCompile group: 'org.apache.commons', name: 'commons-lang3', version: '3.0'
 }
 
 def siteUrl = 'https://github.com/egulias/EmailValidator4J'

src/main/java/emailvalidator4j/lexer/EmailLexer.java

@@ -16,8 +16,10 @@ public class EmailLexer {
 
     public void lex(String input) {
         Pattern pattern = Pattern.compile(
-                "(([a-zA-Z0-9!#$%&'*+\\-/=?^_`{|}~]|[^\\u0000-\\u007F])+[46]?)|([0-9]+)|(\r\n)|(::)|(\\s+?)|(.)|(\\p{Cc}+)", Pattern.CASE_INSENSITIVE | Pattern.UNICODE_CASE
+                "(([a-zA-Z0-9!#$%&'*+\\-/=?^_`{|}~]|[^\\u0000-\\u007F])+[46]?)|([0-9]+)|(\r\n)|(::)|(\\s+?)|(.)|(\\p{Cc}+)",
+                Pattern.CASE_INSENSITIVE | Pattern.UNICODE_CASE
         );
+
         Matcher matcher = pattern.matcher(input);
 
         this.reset();

src/main/java/emailvalidator4j/parser/DomainPart.java

@@ -13,8 +13,8 @@
 final class DomainPart extends Parser {
 
     private static final Pattern subDomainIllegalCharacters = Pattern.compile("[^a-zA-Z0-9\\-\\x00007F-\\u10FFFF]");
-    private static final int DOMAINPART_MAX_LENGTH = 255;
     private static final int LABEL_MAX_LENGTH = 63;
+    public static final int DOMAINPART_MAX_LENGTH = 255;
     private final HashSet<TokenInterface> notAllowedTokens = new HashSet<TokenInterface>(2) {{
         add(Tokens.BACKSLASH);
         add(Tokens.SLASH);

src/main/java/emailvalidator4j/parser/Email.java

@@ -24,9 +24,12 @@ public Email(EmailLexer lexer) {
     }
 
     public void parse(String email) throws InvalidEmail {
-        this.lexer.lex(Optional.ofNullable(email).orElseThrow(() ->
-            new InvalidEmail("Empty email")
-        ));
+
+        String nonEmptyEmail = Optional.ofNullable(email).orElseThrow(() ->
+                new InvalidEmail("Empty email"));
+        this.validateLength(nonEmptyEmail);
+
+        this.lexer.lex(nonEmptyEmail);
 
         if (!this.lexer.find(Tokens.AT)) {
             throw new NoLocalPart("No local part found");
@@ -40,6 +43,14 @@ public void parse(String email) throws InvalidEmail {
         this.domainPartParser.parse(this.lexer.toString());
     }
 
+    private void validateLength(String email) throws InvalidEmail {
+        int maxLength = LocalPart.RFC5321_LOCALPART_MAX_LENGTH + DomainPart.DOMAINPART_MAX_LENGTH + 1;
+
+        if (email.length() > maxLength) {
+            throw new InvalidEmail("email too long");
+        }
+    }
+
     public List getWarnings() {
         List<Warnings> warnings = this.localPartParser.getWarnings();
         warnings.addAll(this.domainPartParser.getWarnings());

src/main/java/emailvalidator4j/parser/LocalPart.java

@@ -13,7 +13,7 @@
 final class LocalPart extends Parser {
     private boolean closingQuote = false;
     private boolean parseDQuote = true;
-    private static int RFC5321_LOCALPART_MAX_LENGTH = 64;
+    public static int RFC5321_LOCALPART_MAX_LENGTH = 64;
 
     LocalPart (EmailLexer lexer) {
         super(lexer);

src/test/java/emailvalidator4j/EmailValidatorTest.java

@@ -3,6 +3,7 @@
 import com.tngtech.java.junit.dataprovider.DataProvider;
 import com.tngtech.java.junit.dataprovider.DataProviderRunner;
 import com.tngtech.java.junit.dataprovider.UseDataProvider;
+import org.apache.commons.lang3.StringUtils;
 import org.junit.Assert;
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -134,4 +135,11 @@ public void warningsAreExposed() {
         validator.isValid("test@[127.0.0.0]");
         Assert.assertFalse(validator.getWarnings().isEmpty());
     }
+
+    @Test
+    public void controlStringOverflow() {
+        String filled = StringUtils.repeat("a", 2000);
+        EmailValidator validator = new EmailValidator();
+        Assert.assertFalse(validator.isValid(filled.concat("@example.com")));
+    }
 }