diff --git a/src/Coduo/PHPMatcher/Exception/UnknownTypeException.php b/src/Coduo/PHPMatcher/Exception/UnknownTypeException.php
index b6a0f832..197e47d1 100644
--- a/src/Coduo/PHPMatcher/Exception/UnknownTypeException.php
+++ b/src/Coduo/PHPMatcher/Exception/UnknownTypeException.php
@@ -4,4 +4,19 @@
 
 class UnknownTypeException extends Exception
 {
+    private $type;
+
+    public function __construct($type)
+    {
+        $this->type = "@" . $type . "@";
+        parent::__construct(sprintf("Type pattern \"%s\" is not supported.", $this->type), 0, null);
+    }
+
+    /**
+     * @return mixed
+     */
+    public function getType()
+    {
+        return $this->type;
+    }
 }
diff --git a/src/Coduo/PHPMatcher/Matcher/JsonMatcher.php b/src/Coduo/PHPMatcher/Matcher/JsonMatcher.php
index 9682a3e3..e033d649 100644
--- a/src/Coduo/PHPMatcher/Matcher/JsonMatcher.php
+++ b/src/Coduo/PHPMatcher/Matcher/JsonMatcher.php
@@ -2,11 +2,10 @@
 
 namespace Coduo\PHPMatcher\Matcher;
 
+use Coduo\PHPMatcher\Matcher\Pattern\Assert\Json;
+
 class JsonMatcher extends Matcher
 {
-    const TRANSFORM_QUOTATION_PATTERN = '/([^"])@([a-zA-Z0-9\.]+)@([^"])/';
-    const TRANSFORM_QUOTATION_REPLACEMENT = '$1"@$2@"$3';
-
     /**
      * @var
      */
@@ -25,12 +24,12 @@ public function __construct(ValueMatcher $matcher)
      */
     public function match($value, $pattern)
     {
-        if (!is_string($value) || !$this->isValidJson($value)) {
+        if (!Json::isValid($value)) {
             return false;
         }
 
-        $pattern = $this->transformPattern($pattern);
-        $match = $this->matcher->match(json_decode($value, true), json_decode($pattern, true));
+        $transformedPattern = Json::transformPattern($pattern);
+        $match = $this->matcher->match(json_decode($value, true), json_decode($transformedPattern, true));
         if (!$match) {
             $this->error = $this->matcher->getError();
             return false;
@@ -44,29 +43,6 @@ public function match($value, $pattern)
      */
     public function canMatch($pattern)
     {
-        if (!is_string($pattern)) {
-            return false;
-        }
-
-        return $this->isValidJson($this->transformPattern($pattern));
+        return Json::isValidPattern($pattern);
     }
-
-    private function isValidJson($string)
-    {
-        @json_decode($string, true);
-
-        return (json_last_error() === JSON_ERROR_NONE);
-    }
-
-    /**
-     * Wraps placeholders which arent wrapped with quotes yet
-     *
-     * @param $pattern
-     * @return mixed
-     */
-    private function transformPattern($pattern)
-    {
-        return preg_replace(self::TRANSFORM_QUOTATION_PATTERN, self::TRANSFORM_QUOTATION_REPLACEMENT, $pattern);
-    }
-
 }
diff --git a/src/Coduo/PHPMatcher/Matcher/Pattern/Assert/Json.php b/src/Coduo/PHPMatcher/Matcher/Pattern/Assert/Json.php
new file mode 100644
index 00000000..d9f6d45f
--- /dev/null
+++ b/src/Coduo/PHPMatcher/Matcher/Pattern/Assert/Json.php
@@ -0,0 +1,52 @@
+<?php
+
+namespace Coduo\PHPMatcher\Matcher\Pattern\Assert;
+
+class Json
+{
+    const TRANSFORM_QUOTATION_PATTERN = '/([^"])@([a-zA-Z0-9\.]+)@([^"])/';
+    const TRANSFORM_QUOTATION_REPLACEMENT = '$1"@$2@"$3';
+
+    /**
+     * @param string $value
+     * @return bool
+     */
+    public static function isValid($value)
+    {
+        if (!is_string($value)) {
+            return false;
+        }
+
+        if (null === json_decode($value) && JSON_ERROR_NONE !== json_last_error()) {
+            return false;
+        }
+
+        return true;
+    }
+
+    /**
+     * Before checking json it wraps type patterns (@type@) with quotes ("@type@")
+     *
+     * @param string $value
+     * @return bool
+     */
+    public static function isValidPattern($value)
+    {
+        if (!is_string($value)) {
+            return false;
+        }
+
+        return self::isValid(self::transformPattern($value));
+    }
+
+    /**
+     * Wraps placeholders which arent wrapped with quotes yet
+     *
+     * @param $pattern
+     * @return mixed
+     */
+    public static function transformPattern($pattern)
+    {
+        return preg_replace(self::TRANSFORM_QUOTATION_PATTERN, self::TRANSFORM_QUOTATION_REPLACEMENT, $pattern);
+    }
+}
diff --git a/src/Coduo/PHPMatcher/Matcher/Pattern/Assert/Xml.php b/src/Coduo/PHPMatcher/Matcher/Pattern/Assert/Xml.php
new file mode 100644
index 00000000..6ad08a91
--- /dev/null
+++ b/src/Coduo/PHPMatcher/Matcher/Pattern/Assert/Xml.php
@@ -0,0 +1,24 @@
+<?php
+
+namespace Coduo\PHPMatcher\Matcher\Pattern\Assert;
+
+class Xml
+{
+    /**
+     * @param $value
+     * @return bool
+     */
+    public static function isValid($value)
+    {
+        if (!is_string($value)) {
+            return false;
+
+        }
+        $xml = @simplexml_load_string($value);
+        if (!$xml instanceof \SimpleXMLElement) {
+            return false;
+        }
+
+        return true;
+    }
+}
diff --git a/src/Coduo/PHPMatcher/Matcher/Pattern/RegexConverter.php b/src/Coduo/PHPMatcher/Matcher/Pattern/RegexConverter.php
index 554bcd38..c42aa221 100644
--- a/src/Coduo/PHPMatcher/Matcher/Pattern/RegexConverter.php
+++ b/src/Coduo/PHPMatcher/Matcher/Pattern/RegexConverter.php
@@ -6,9 +6,9 @@
 
 class RegexConverter
 {
-    public function toRegex(TypePattern $type)
+    public function toRegex(TypePattern $typePattern)
     {
-        switch ($type->getType()) {
+        switch ($typePattern->getType()) {
             case 'string':
             case 'wildcard':
             case '*':
@@ -20,7 +20,7 @@ public function toRegex(TypePattern $type)
             case 'double':
                 return "(\\-?[0-9]*[\\.|\\,][0-9]*)";
             default:
-                throw new UnknownTypeException();
+                throw new UnknownTypeException($typePattern->getType());
         }
     }
 }
diff --git a/src/Coduo/PHPMatcher/Matcher/TextMatcher.php b/src/Coduo/PHPMatcher/Matcher/TextMatcher.php
index 4a5d0de6..73b85962 100644
--- a/src/Coduo/PHPMatcher/Matcher/TextMatcher.php
+++ b/src/Coduo/PHPMatcher/Matcher/TextMatcher.php
@@ -2,6 +2,9 @@
 
 namespace Coduo\PHPMatcher\Matcher;
 
+use Coduo\PHPMatcher\Exception\UnknownTypeException;
+use Coduo\PHPMatcher\Matcher\Pattern\Assert\Json;
+use Coduo\PHPMatcher\Matcher\Pattern\Assert\Xml;
 use Coduo\PHPMatcher\Matcher\Pattern\TypePattern;
 use Coduo\PHPMatcher\Parser;
 use Coduo\PHPMatcher\Matcher\Pattern\RegexConverter;
@@ -46,7 +49,12 @@ public function match($value, $pattern)
         $patternRegex = $pattern;
         $patternsReplacedWithRegex = $this->replaceTypePatternsWithPlaceholders($patternRegex);
         $patternRegex = $this->prepareRegex($patternRegex);
-        $patternRegex = $this->replacePlaceholderWithPatternRegexes($patternRegex, $patternsReplacedWithRegex);
+        try {
+            $patternRegex = $this->replacePlaceholderWithPatternRegexes($patternRegex, $patternsReplacedWithRegex);
+        } catch (UnknownTypeException $exception) {
+            $this->error = sprintf(sprintf("Type pattern \"%s\" is not supported by TextMatcher.", $exception->getType()));
+            return false;
+        }
 
         if (!preg_match($patternRegex, $value, $matchedValues)) {
             $this->error = sprintf("\"%s\" does not match \"%s\" pattern", $value, $pattern);
@@ -79,6 +87,14 @@ public function canMatch($pattern)
             return false;
         }
 
+        if (Json::isValidPattern($pattern)) {
+            return false;
+        }
+
+        if (Xml::isValid($pattern)) {
+            return false;
+        }
+
         return true;
     }
 
diff --git a/src/Coduo/PHPMatcher/Matcher/XmlMatcher.php b/src/Coduo/PHPMatcher/Matcher/XmlMatcher.php
index 6b00120a..2179bc81 100644
--- a/src/Coduo/PHPMatcher/Matcher/XmlMatcher.php
+++ b/src/Coduo/PHPMatcher/Matcher/XmlMatcher.php
@@ -2,6 +2,7 @@
 
 namespace Coduo\PHPMatcher\Matcher;
 
+use Coduo\PHPMatcher\Matcher\Pattern\Assert\Xml;
 use LSS\XML2Array;
 
 class XmlMatcher extends Matcher
@@ -24,7 +25,7 @@ public function __construct(ValueMatcher $matcher)
      */
     public function match($value, $pattern)
     {
-        if (!is_string($value) || !$this->isValidXml($value) || !$this->isValidXml($pattern)) {
+        if (!Xml::isValid($value) || !Xml::isValid($pattern)) {
             return false;
         }
 
@@ -45,22 +46,6 @@ public function match($value, $pattern)
      */
     public function canMatch($pattern)
     {
-        if (!is_string($pattern)) {
-            return false;
-        }
-
-        return $this->isValidXml($pattern);
-    }
-
-    private function isValidXml($string)
-    {
-        $xml = @simplexml_load_string($string);
-
-        if (!$xml instanceof \SimpleXMLElement) {
-
-            return false;
-        }
-
-        return true;
+        return Xml::isValid($pattern);
     }
 }
diff --git a/tests/Coduo/PHPMatcher/Matcher/TextMatcherTest.php b/tests/Coduo/PHPMatcher/Matcher/TextMatcherTest.php
index 79f2800f..2434ecc5 100644
--- a/tests/Coduo/PHPMatcher/Matcher/TextMatcherTest.php
+++ b/tests/Coduo/PHPMatcher/Matcher/TextMatcherTest.php
@@ -45,6 +45,48 @@ public function test_positive_matches($value, $pattern, $expectedResult)
         $this->assertEquals($expectedResult, $this->matcher->match($value, $pattern));
     }
 
+    public function test_ignore_valid_json_patterns()
+    {
+        $jsonPattern = json_encode(array(
+            'users' => array(
+                array('id' => '@number@', 'name' => 'Norbert'),
+                array('id' => '@number@', 'name' => 'Michal')
+            )
+        ));
+
+        $this->assertFalse($this->matcher->canMatch($jsonPattern));
+    }
+
+    public function test_ignore_valid_xml_patterns()
+    {
+        $xmlPattern = <<<XML
+<?xml version="1.0"?>
+<soap:Envelope
+xmlns:soap="http://www.w3.org/2001/12/soap-envelope"
+soap:encodingStyle="http://www.w3.org/2001/12/soap-encoding">
+
+<soap:Body xmlns:m="http://www.example.org/stock">
+  <m:GetStockPrice>
+    <m:StockName>@string@</m:StockName>
+    <m:StockValue>Any Value</m:StockValue>
+  </m:GetStockPrice>
+</soap:Body>
+
+</soap:Envelope>
+XML;
+
+        $this->assertFalse($this->matcher->canMatch($xmlPattern));
+    }
+
+    public function test_error_when_unsupported_type_pattern_used()
+    {
+        $pattern = "lorem ipsum @null@ bla bla";
+        $value = "lorem ipsum bla bla";
+
+        $this->assertFalse($this->matcher->match($value, $pattern));
+        $this->assertSame("Type pattern \"@null@\" is not supported by TextMatcher.", $this->matcher->getError());
+    }
+
     public function matchingData()
     {
         return array(
diff --git a/tests/Coduo/PHPMatcher/MatcherTest.php b/tests/Coduo/PHPMatcher/MatcherTest.php
index 58df8b1b..dd66dd49 100644
--- a/tests/Coduo/PHPMatcher/MatcherTest.php
+++ b/tests/Coduo/PHPMatcher/MatcherTest.php
@@ -203,6 +203,16 @@ public function test_text_matcher()
         $this->assertTrue(match($value, $pattern));
     }
 
+
+    public function test_error_when_json_value_does_not_match_json_pattern()
+    {
+        $pattern = '{"a": @null@, "b": 4}';
+        $value = '{"a": null, "b": 5}';
+
+        $this->assertFalse($this->matcher->match($value, $pattern));
+        $this->assertSame('"5" does not match "4".', $this->matcher->getError());
+    }
+
     public function test_matcher_with_captures()
     {
         $this->assertTrue($this->matcher->match(