diff --git a/Test/TestLexer.hs b/Test/TestLexer.hs
index 848cb4d..ddd55c9 100644
--- a/Test/TestLexer.hs
+++ b/Test/TestLexer.hs
@@ -15,6 +15,9 @@ testIdentifier = TestCase $ assertEqual "scan 'identifier'" [Identifier "identif
 testShortIdentifier = TestCase $ assertEqual "scan 'i'" [Identifier "i"] $ alexScanTokens "i"
 testIdentifierWithNumber = TestCase $ assertEqual "scan 'i2'" [Identifier "i2"] $ alexScanTokens "i2"
 
+testKeywordBreak = TestCase $ assertEqual "scan 'break'" [BREAK] $ alexScanTokens "break"
+testKeywordInt = TestCase $ assertEqual "scan 'int'" [INT] $ alexScanTokens "int"
+
 tests = TestList [
     TestLabel "TestCommentSomething" testCommentSomething,
     TestLabel "TestEmptyComment" testEmptyComment,
@@ -22,5 +25,7 @@ tests = TestList [
     TestLabel "TestLineCommentEnds" testLineCommentEnds,
     TestLabel "TestIdentifier" testIdentifier,
     TestLabel "TestShortIdentifier" testShortIdentifier,
-    TestLabel "TestIdentifierWithNumber" testIdentifierWithNumber
+    TestLabel "TestIdentifierWithNumber" testIdentifierWithNumber,
+    TestLabel "TestKeywordBreak" testKeywordBreak,
+    TestLabel "TestKeywordInt" testKeywordInt
     ]
\ No newline at end of file
diff --git a/src/Parser/Lexer.x b/src/Parser/Lexer.x
index d500674..d961036 100644
--- a/src/Parser/Lexer.x
+++ b/src/Parser/Lexer.x
@@ -14,12 +14,112 @@ tokens :-
     $white ;
     "/*"(.|\n)*"*/" ;
     "//".* ;
+    -- keywords
+    "abstract" { \_ -> ABSTRACT }
+    "assert" { \_ -> BOOLEAN }
+    "boolean" { \_ -> BOOLEAN}
+    "break" { \_ -> BREAK}
+    "byte" { \_ -> BYTE}
+    "case" { \_ -> CASE}
+    "catch" { \_ -> CATCH}
+    "char" { \_ -> CHAR}
+    "class" { \_ -> CLASS}
+    "const" { \_ -> CONST}
+    "continue" { \_ -> CONTINUE}
+    "default" { \_ -> DEFAULT}
+    "do" { \_ -> DO}
+    "double" { \_ -> DOUBLE}
+    "else" { \_ -> ELSE}
+    "enum" { \_ -> ENUM}
+    "extends" { \_ -> EXTENDS}
+    "final" { \_ -> FINAL}
+    "finally" { \_ -> FINALLY}
+    "float" { \_ -> FLOAT}
+    "for" { \_ -> FOR}
+    "if" { \_ -> IF}
+    "goto" { \_ -> GOTO}
+    "implements" { \_ -> IMPLEMENTS}
+    "import" { \_ -> IMPORT}
+    "instanceof" { \_ -> INSTANCEOF}
+    "int" { \_ -> INT}
+    "long" { \_ -> LONG}
+    "native" { \_ -> NATIVE}
+    "new" { \_ -> NEW}
+    "package" { \_ -> PACKAGE}
+    "private" { \_ -> PRIVATE}
+    "protected" { \_ -> PROTECTED}
+    "public" { \_ -> PUBLIC}
+    "return" { \_ -> RETURN}
+    "short" { \_ -> SHORT}
+    "static" { \_ -> STATIC}
+    "strictfp" { \_ -> STRICTFP}
+    "super" { \_ -> SUPER}
+    "switch" { \_ -> SWITCH}
+    "synchronized" { \_ -> SYNCHRONIZED}
+    "this" { \_ -> THIS}
+    "throw" { \_ -> THROW}
+    "throws" { \_ -> THROWS}
+    "transient" { \_ -> TRANSIENT}
+    "try" { \_ -> TRY}
+    "void" { \_ -> VOID}
+    "volatile" { \_ -> VOLATILE}
+    "while" { \_ -> WHILE}
+    -- end keywords
     $JavaLetter$JavaLetterOrDigit*  { \s -> Identifier s }
 
-
 {
 data Token 
-    = Identifier String
+    = ABSTRACT
+    | ASSERT
+    | BOOLEAN
+    | BREAK
+    | BYTE
+    | CASE
+    | CATCH
+    | CHAR
+    | CLASS
+    | CONST
+    | CONTINUE
+    | DEFAULT
+    | DO
+    | DOUBLE
+    | ELSE
+    | ENUM
+    | EXTENDS
+    | FINAL
+    | FINALLY
+    | FLOAT
+    | FOR
+    | IF
+    | GOTO
+    | IMPLEMENTS
+    | IMPORT
+    | INSTANCEOF
+    | INT
+    | INTERFACE
+    | LONG
+    | NATIVE
+    | NEW
+    | PACKAGE
+    | PRIVATE
+    | PROTECTED
+    | PUBLIC
+    | RETURN
+    | SHORT
+    | STATIC
+    | STRICTFP
+    | SUPER
+    | SWITCH
+    | SYNCHRONIZED
+    | THIS
+    | THROW
+    | THROWS
+    | TRANSIENT
+    | TRY
+    | VOID
+    | VOLATILE
+    | WHILE
+    | Identifier String
     deriving(Eq,Show)
 
 }
\ No newline at end of file