diff --git a/src/main/java/de/kosit/validationtool/config/XPathBuilder.java b/src/main/java/de/kosit/validationtool/config/XPathBuilder.java
index 83cbe5a..c5f60b8 100644
--- a/src/main/java/de/kosit/validationtool/config/XPathBuilder.java
+++ b/src/main/java/de/kosit/validationtool/config/XPathBuilder.java
@@ -13,7 +13,6 @@ import org.apache.commons.lang3.StringUtils;
 
 import lombok.AccessLevel;
 import lombok.Data;
-import lombok.Getter;
 import lombok.RequiredArgsConstructor;
 import lombok.Setter;
 import lombok.extern.slf4j.Slf4j;
@@ -42,9 +41,15 @@ class XPathBuilder implements Builder<XPathExecutable> {
     private XPathExecutable executable;
 
     @Setter(AccessLevel.PACKAGE)
-    @Getter(AccessLevel.PACKAGE)
     private Map<String, String> namespaces;
 
+    Map<String, String> getNamespaces() {
+        if (this.namespaces == null) {
+            this.namespaces = new HashMap<>();
+        }
+        return this.namespaces;
+    }
+
     /**
      * Returns the xpath expression.
      * 
@@ -66,7 +71,7 @@ class XPathBuilder implements Builder<XPathExecutable> {
         }
         try {
             if (this.executable == null) {
-                this.executable = repository.createXPath(this.xpath, this.namespaces);
+                this.executable = repository.createXPath(this.xpath, getNamespaces());
             } else {
                 this.xpath = extractExpression();
                 extractNamespaces();
@@ -81,19 +86,15 @@ class XPathBuilder implements Builder<XPathExecutable> {
     }
 
     private void extractNamespaces() {
-        if (this.namespaces == null) {
-            this.namespaces = new HashMap<>();
-        }
+
         final Map<String, String> ns = new HashMap<>();
         final Iterator<String> iterator = this.executable.getUnderlyingExpression().getInternalExpression().getRetainedStaticContext()
                 .iteratePrefixes();
         final Iterable<String> iterable = () -> iterator;
         StreamSupport.stream(iterable.spliterator(), false).filter(e -> !ArrayUtils.contains(IGNORED_PREFIXES, e))
-                .filter(StringUtils::isNotBlank).forEach(e -> {
-                    ns.put(e, this.executable.getUnderlyingExpression().getInternalExpression().getRetainedStaticContext()
-                            .getURIForPrefix(e, false));
-                });
-        this.namespaces.putAll(ns);
+                .filter(StringUtils::isNotBlank).forEach(e -> ns.put(e, this.executable.getUnderlyingExpression().getInternalExpression()
+                        .getRetainedStaticContext().getURIForPrefix(e, false)));
+        getNamespaces().putAll(ns);
 
     }
 
diff --git a/src/main/java/de/kosit/validationtool/impl/ContentRepository.java b/src/main/java/de/kosit/validationtool/impl/ContentRepository.java
index 6fd7a5b..84757d4 100644
--- a/src/main/java/de/kosit/validationtool/impl/ContentRepository.java
+++ b/src/main/java/de/kosit/validationtool/impl/ContentRepository.java
@@ -143,7 +143,7 @@ public class ContentRepository {
             throw new IllegalStateException("Can not compile xslt executable for uri " + uri, e);
         } finally {
             if (!listener.hasErrors() && listener.hasEvents()) {
-                log.warn("Received warnings while loading a xslt script {}", uri);
+                log.warn("Received warnings or errors while loading a xslt script {}", uri);
                 listener.getErrors().forEach(e -> e.log(log));
             }
         }
diff --git a/src/test/java/de/kosit/validationtool/config/XPathBuilderTest.java b/src/test/java/de/kosit/validationtool/config/XPathBuilderTest.java
new file mode 100644
index 0000000..30d3af1
--- /dev/null
+++ b/src/test/java/de/kosit/validationtool/config/XPathBuilderTest.java
@@ -0,0 +1,116 @@
+package de.kosit.validationtool.config;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+
+import org.apache.commons.lang3.RandomStringUtils;
+import org.junit.Test;
+
+import de.kosit.validationtool.impl.ContentRepository;
+import de.kosit.validationtool.impl.Helper.Simple;
+import de.kosit.validationtool.impl.model.Result;
+
+import net.sf.saxon.s9api.XPathExecutable;
+
+/**
+ * Tests {@link XPathBuilder}.
+ * 
+ * @author Andreas Penski
+ */
+public class XPathBuilderTest {
+
+    @Test
+    public void testSimpleString() {
+        final String name = RandomStringUtils.randomAlphanumeric(5);
+        final XPathBuilder b = new XPathBuilder(name);
+        b.setXpath("//*");
+        final Result<XPathExecutable, String> result = b.build(Simple.createContentRepository());
+        assertThat(result).isNotNull();
+        assertThat(result.isValid()).isTrue();
+        assertThat(b.getNamespaces()).isNotNull();
+        assertThat(b.getNamespaces()).isEmpty();
+        assertThat(b.getXPath()).isNotEmpty();
+        assertThat(b.getName()).isNotEmpty();
+    }
+
+    @Test
+    public void testStringWithNamespace() {
+        final String name = RandomStringUtils.randomAlphanumeric(5);
+        final XPathBuilder b = new XPathBuilder(name);
+        final Map<String, String> ns = new HashMap<>();
+        ns.put("p", "http://somens");
+        b.setNamespaces(ns);
+        b.setXpath("//p:*");
+        final Result<XPathExecutable, String> result = b.build(Simple.createContentRepository());
+        assertThat(result).isNotNull();
+        assertThat(result.isValid()).isTrue();
+        assertThat(b.getNamespaces()).isNotEmpty();
+        assertThat(b.getXPath()).isNotEmpty();
+    }
+
+    @Test
+    public void testStringWithUnknownNamespace() {
+        final String name = RandomStringUtils.randomAlphanumeric(5);
+        final XPathBuilder b = new XPathBuilder(name);
+        final Map<String, String> ns = new HashMap<>();
+        ns.put("p", "http://somens");
+        b.setNamespaces(ns);
+        b.setXpath("//u:*");
+        final Result<XPathExecutable, String> result = b.build(Simple.createContentRepository());
+        assertThat(result).isNotNull();
+        assertThat(result.isValid()).isFalse();
+    }
+
+    @Test
+    public void testExecutable() {
+        final String name = RandomStringUtils.randomAlphanumeric(5);
+        final ContentRepository repository = Simple.createContentRepository();
+        final XPathExecutable xpath = repository.createXPath("//*", Collections.emptyMap());
+        final XPathBuilder b = new XPathBuilder(name);
+        b.setExecutable(xpath);
+        final Result<XPathExecutable, String> result = b.build(repository);
+        assertThat(result).isNotNull();
+        assertThat(result.isValid()).isTrue();
+        assertThat(b.getNamespaces()).isEmpty();
+        assertThat(b.getXPath()).isNotEmpty();
+    }
+
+    @Test
+    public void testExecutableWithNamespace() {
+        final String name = RandomStringUtils.randomAlphanumeric(5);
+        final ContentRepository repository = Simple.createContentRepository();
+        final Map<String, String> ns = new HashMap<>();
+        ns.put("p", "http://somens");
+        final XPathExecutable xpath = repository.createXPath("//p:*", ns);
+        final XPathBuilder b = new XPathBuilder(name);
+        b.setExecutable(xpath);
+        final Result<XPathExecutable, String> result = b.build(repository);
+        assertThat(result).isNotNull();
+        assertThat(result.isValid()).isTrue();
+        assertThat(b.getNamespaces()).isNotEmpty();
+        assertThat(b.getNamespaces()).containsKey("p");
+        assertThat(b.getXPath()).isNotEmpty();
+    }
+
+    @Test
+    public void testNoName() {
+        final XPathBuilder b = new XPathBuilder(null);
+        b.setXpath("//*");
+        final Result<XPathExecutable, String> result = b.build(Simple.createContentRepository());
+        assertThat(result).isNotNull();
+        assertThat(result.isValid()).isTrue();
+        assertThat(b.getName()).isNull();
+    }
+
+    @Test
+    public void testNoConfig() {
+        final String name = RandomStringUtils.randomAlphanumeric(5);
+        final XPathBuilder b = new XPathBuilder(name);
+        final Result<XPathExecutable, String> result = b.build(Simple.createContentRepository());
+        assertThat(result).isNotNull();
+        assertThat(result.isValid()).isFalse();
+    }
+}