Replaced 'new URL' with a call to a new URLFactory

pom.xml

@@ -19,7 +19,7 @@
     <modelVersion>4.0.0</modelVersion>
     <groupId>com.networknt</groupId>
     <artifactId>json-schema-validator</artifactId>
-    <version>0.1.10</version>
+    <version>0.1.10-escenic</version>
     <description>A json schema validator that supports draft v4</description>
     <url>https://github.com/networknt/json-schema-validator</url>
     <name>JsonSchemaValidator</name>

src/main/java/com/networknt/schema/BaseJsonValidator.java

@@ -17,6 +17,7 @@
 package com.networknt.schema;
 
 import com.fasterxml.jackson.databind.JsonNode;
+import com.networknt.schema.url.URLFactory;
 import org.apache.commons.lang3.StringUtils;
 import org.slf4j.Logger;
 
@@ -77,8 +78,14 @@ protected JsonSchema obainSubSchemaNode(JsonNode schemaNode){
 
         try {
             JsonSchemaFactory factory = new JsonSchemaFactory();
-            URL url = new URL(node.textValue());
-            return factory.getSchema(url);
+            String text = node.textValue();
+            if (text == null) {
+                return null;
+            }
+            else {
+                URL url = URLFactory.toURL(node.textValue());
+                return factory.getSchema(url);
+            }
         } catch (MalformedURLException e) {
             return null;
         }

src/main/java/com/networknt/schema/RefValidator.java

@@ -18,6 +18,7 @@
 
 import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.ObjectMapper;
+import com.networknt.schema.url.URLFactory;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -53,7 +54,7 @@ public RefValidator(String schemaPath, JsonNode schemaNode, JsonSchema parentSch
 
             JsonSchemaFactory factory = new JsonSchemaFactory(mapper);
             try {
-                URL url = new URL(schemaUrl);
+                URL url = URLFactory.toURL(schemaUrl);
                 parentSchema = factory.getSchema(url);
             } catch (MalformedURLException e) {
                 InputStream is = Thread.currentThread().getContextClassLoader().getResourceAsStream(schemaUrl);
@@ -89,7 +90,7 @@ private String obtainAbsolutePath(JsonSchema parentSchema, String schemaUrl) {
 		if(schemaRef.startsWith(REF_DOMAIN)){
 			// from domain add ref
 			try {
-				URL url = new URL(baseSchemaUrl);
+				URL url = URLFactory.toURL(baseSchemaUrl);
 				baseSchemaUrl = url.getProtocol()+"//"+url.getHost();
 			} catch (MalformedURLException e) {
 				e.printStackTrace();

src/main/java/com/networknt/schema/url/ClasspathURLStreamHandler.java

@@ -0,0 +1,85 @@
+package com.networknt.schema.url;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.URL;
+import java.net.URLConnection;
+import java.net.URLStreamHandler;
+
+/**
+ * An {@link URLStreamHandler} capable of loading resources from the classpath.
+ *
+ * @author <a href="mailto:[email protected]">Kenneth Waldenstrom</a>
+ */
+class ClasspathURLStreamHandler extends URLStreamHandler {
+  private final static String CLASSPATH_PREFIX = "classpath:";
+  private final static String RESOURCE_PREFIX = "resource:";
+
+  boolean supports(final String pURL) {
+    return pURL.startsWith(CLASSPATH_PREFIX) || pURL.startsWith(RESOURCE_PREFIX);
+  }
+
+  @Override
+  protected URLConnection openConnection(final URL pURL) throws IOException {
+    return new ClassPathURLConnection(pURL);
+  }
+
+  class ClassPathURLConnection extends URLConnection {
+
+    private Class<?> mHost = null;
+
+    protected ClassPathURLConnection(URL pURL) {
+      super(pURL);
+    }
+
+    @Override
+    public final void connect() throws IOException {
+      String className = url.getHost();
+      try {
+        if (className != null && className.length() > 0) {
+          mHost = Class.forName(className);
+        }
+        connected = true;
+      }
+      catch (ClassNotFoundException e) {
+        throw new IOException("Class not found: " + e.toString());
+      }
+    }
+
+    @Override
+    public final InputStream getInputStream() throws IOException {
+      if (!connected) {
+        connect();
+      }
+      return getResourceAsStream(url);
+    }
+
+    private InputStream getResourceAsStream(URL pURL) throws IOException {
+      String path = pURL.getPath();
+
+      if (path.startsWith("/")) {
+        path = path.substring(1);
+      }
+
+      InputStream stream;
+      if (mHost != null) {
+        stream = mHost.getClassLoader().getResourceAsStream(path);
+      }
+      else {
+        stream = Thread.currentThread().getContextClassLoader().getResourceAsStream(path);
+        if (stream == null) {
+          stream = getClass().getClassLoader().getResourceAsStream(path);
+        }
+        if (stream == null) {
+          stream = ClassLoader.getSystemResourceAsStream(path);
+        }
+      }
+      if (stream == null) {
+        throw new IOException("Resource " + path + " not found in classpath.");
+      }
+      return stream;
+    }
+  }
+
+
+}

src/main/java/com/networknt/schema/url/URLFactory.java

@@ -0,0 +1,28 @@
+package com.networknt.schema.url;
+
+import java.net.MalformedURLException;
+import java.net.URL;
+
+/**
+ * A factory for creating {@link URL}'s. This factory creates {@link URL}'s that in additional to the standard {@link URL}'s
+ * capability of loading resources using http, https, file, etc. also makes it possible to load resources from
+ * the applications classpath. To load a resource from classpath, the url must be prefixed either with <i>classpath:</i>
+ * or <i>resource:</i>
+ *
+ * To ensure that we support classpath resources, this class should be used instead of <code>new URL(pURL)</code>
+ *
+ * @author <a href="mailto:[email protected]">Kenneth Waldenstrom</a>
+ */
+public class URLFactory {
+  private static final ClasspathURLStreamHandler sClasspathURLStreamHandler = new ClasspathURLStreamHandler();
+
+  /**
+   * Creates an {@link URL} based on the provided string
+   * @param pURL the url
+   * @return a {@link URL}
+   * @throws MalformedURLException if the url is not a proper URL
+   */
+  public static URL toURL(final String pURL) throws MalformedURLException {
+    return new URL(null, pURL, sClasspathURLStreamHandler.supports(pURL) ? sClasspathURLStreamHandler : null);
+  }
+}