JabRef · sfahaddev · Mar 22, 2025 · Mar 22, 2025 · Mar 23, 2025 · Mar 23, 2025
diff --git a/jablib/src/main/java/org/jabref/logic/importer/util/FileFieldParser.java b/jablib/src/main/java/org/jabref/logic/importer/util/FileFieldParser.java
@@ -173,7 +173,7 @@ static LinkedFile convert(List<String> entry) {
                     // there is no Path.isValidPath(String) method
                     field = new LinkedFile(entry.getFirst(), Path.of(pathStr), entry.get(2));
                 } catch (InvalidPathException e) {
-                    // Ignored
+                    // Use string if path is invalid
                     LOGGER.debug("Invalid path object, continuing with string", e);
                     field = new LinkedFile(entry.getFirst(), pathStr, entry.get(2));
                 }

diff --git a/jablib/src/main/java/org/jabref/logic/util/URLUtil.java b/jablib/src/main/java/org/jabref/logic/util/URLUtil.java
@@ -17,6 +17,8 @@
  * For GUI-oriented URL utilities see {@link org.jabref.gui.fieldeditors.URLUtil}.
  */
 public class URLUtil {
+    private static final String PROTOCOL_SEPARATOR = "://";
+    private static final Pattern SCHEME_PREFIX = Pattern.compile("^[a-zA-Z]+://.*");
 
     private static final String URL_REGEX = "(?i)\\b((?:https?|ftp)://[^\\s]+)";
 
@@ -79,31 +81,46 @@ public static String cleanGoogleSearchURL(String url) {
     /**
      * Checks whether the given String is a URL.
      * <p>
-     * Currently only checks for a protocol String.
+     * A valid URL must have a scheme (e.g., "http", "https",
+     * "ftp") and an authority (e.g., "example.com").
+     * See <a href="https://en.wikipedia.org/wiki/URL#Syntax">
+     * URL Syntax</a> for details.
      *
      * @param url the String to check for a URL
      * @return true if <c>url</c> contains a valid URL
      */
     public static boolean isURL(String url) {
+        if (!SCHEME_PREFIX.matcher(url).matches()) {
+            return false;
+        }
         try {
-            create(url);
+            createUri(url);
             return true;
-        } catch (MalformedURLException | IllegalArgumentException e) {
+        } catch (IllegalArgumentException e) {
             return false;
         }
     }
 
     /**
      * Creates a {@link URL} object from the given string URL.
+     * <p>
+     * If the given URL string does not contain a protocol (e.g., "example.com"),
+     * "https://" is automatically added to ensure a valid URL format.
+     * This prevents errors when handling URLs without explicit protocols.
      *
      * @param url the URL string to be converted into a {@link URL}.
      * @return the {@link URL} object created from the string URL.
      * @throws MalformedURLException if the URL is malformed and cannot be converted to a {@link URL}.
      */
     public static URL create(String url) throws MalformedURLException {
-        return createUri(url).toURL();
-    }
+        if (!url.contains(PROTOCOL_SEPARATOR)) {
+            url = "https://" + url;
+        }
 
+        URI uri = createUri(url);
+        return uri.toURL();
+    }
+
     /**
      * Creates a {@link URI} object from the given string URL.
      * This method attempts to convert the given URL string into a {@link URI} object.

diff --git a/jablib/src/test/java/org/jabref/logic/net/URLUtilTest.java b/jablib/src/test/java/org/jabref/logic/net/URLUtilTest.java
@@ -1,10 +1,13 @@
 package org.jabref.logic.net;
 
 import java.net.URI;
+import java.net.URL;
 
 import org.jabref.logic.util.URLUtil;
 
 import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.CsvSource;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertFalse;
@@ -87,4 +90,29 @@ void createUriShouldHandlePipeCharacter() {
         URI uri = URLUtil.createUri(input);
         assertEquals("http://example.com/test%7Cfile", uri.toString());
     }
+
+    @ParameterizedTest
+    @CsvSource({
+    // Relative URLs (should default to HTTPS)
+    "www.example.com, https://www.example.com",
+    "example.com, https://example.com",
+
+    // Absolute URLs (should remain unchanged)
+    "http://www.example.com, http://www.example.com",
+    "https://www.example.com, https://www.example.com"
+    })
+    void createShouldHandleURLs(String expected, String input) throws Exception {
+        URL url = URLUtil.create(input);
+        assertEquals(expected, url.toString());
+    }
+
+    @ParameterizedTest
+    @CsvSource({
+        "ftp://example.com, ftp://example.com",
+        "file:///path/to/file, file:/path/to/file"
+    })
+    void createShouldHandleOtherProtocols(String expectedUrl, String inputUrl) throws Exception {
+        URL actualUrl = URLUtil.create(inputUrl);
+        assertEquals(expectedUrl, actualUrl.toString());
+    }
 }
diff --git a/src/test/java/org/jabref/logic/net/URLUtilTest.java b/src/test/java/org/jabref/logic/net/URLUtilTest.java
@@ -0,0 +1,119 @@
+package org.jabref.logic.net;
+
+import java.net.URI;
+import java.net.URL;
+
+import org.jabref.logic.util.URLUtil;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.CsvSource;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+class URLUtilTest {
+
+    @Test
+    void cleanGoogleSearchURL() throws Exception {
+        // empty text
+        assertEquals("", URLUtil.cleanGoogleSearchURL(""));
+        assertEquals(" ", URLUtil.cleanGoogleSearchURL(" "));
+        // no URL
+        assertEquals("this is no url!", URLUtil.cleanGoogleSearchURL("this is no url!"));
+        // no Google search URL
+        assertEquals("http://dl.acm.org/citation.cfm?id=321811", URLUtil.cleanGoogleSearchURL("http://dl.acm.org/citation.cfm?id=321811"));
+        // malformed Google URL
+        assertEquals("https://www.google.de/url♥", URLUtil.cleanGoogleSearchURL("https://www.google.de/url♥"));
+        // no queries
+        assertEquals("https://www.google.de/url", URLUtil.cleanGoogleSearchURL("https://www.google.de/url"));
+        assertEquals("https://www.google.de/url?", URLUtil.cleanGoogleSearchURL("https://www.google.de/url?"));
+        // no multiple queries
+        assertEquals("https://www.google.de/url?key=value", URLUtil.cleanGoogleSearchURL("https://www.google.de/url?key=value"));
+        // no key values
+        assertEquals("https://www.google.de/url?key", URLUtil.cleanGoogleSearchURL("https://www.google.de/url?key"));
+        assertEquals("https://www.google.de/url?url", URLUtil.cleanGoogleSearchURL("https://www.google.de/url?url"));
+        assertEquals("https://www.google.de/url?key=", URLUtil.cleanGoogleSearchURL("https://www.google.de/url?key="));
+        // no url param
+        assertEquals("https://www.google.de/url?key=value&key2=value2", URLUtil.cleanGoogleSearchURL("https://www.google.de/url?key=value&key2=value2"));
+        // no url param value
+        assertEquals("https://www.google.de/url?url=", URLUtil.cleanGoogleSearchURL("https://www.google.de/url?url="));
+        // url param value no URL
+        assertEquals("https://www.google.de/url?url=this+is+no+url", URLUtil.cleanGoogleSearchURL("https://www.google.de/url?url=this+is+no+url"));
+        // Http
+        assertEquals(
+                "http://moz.com/ugc/the-ultimate-guide-to-the-google-search-parameters",
+                URLUtil.cleanGoogleSearchURL("http://www.google.de/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0CCEQFjAAahUKEwjJurHd2sfHAhWBsxQKHSrEAaM&url=http%3A%2F%2Fmoz.com%2Fugc%2Fthe-ultimate-guide-to-the-google-search-parameters&ei=0THeVYmOJIHnUqqIh5gK&usg=AFQjCNHnid_r_d2LP8_MqvI7lQnTC3lB_g&sig2=ICzxDroG2ENTJSUGmdhI2w"));
+        // Https
+        assertEquals(
+                "https://moz.com/ugc/the-ultimate-guide-to-the-google-search-parameters",
+                URLUtil.cleanGoogleSearchURL("https://www.google.de/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0CCEQFjAAahUKEwjJurHd2sfHAhWBsxQKHSrEAaM&url=https%3A%2F%2Fmoz.com%2Fugc%2Fthe-ultimate-guide-to-the-google-search-parameters&ei=0THeVYmOJIHnUqqIh5gK&usg=AFQjCNHnid_r_d2LP8_MqvI7lQnTC3lB_g&sig2=ICzxDroG2ENTJSUGmdhI2w"));
+        // root domain
+        assertEquals(
+                "https://moz.com/ugc/the-ultimate-guide-to-the-google-search-parameters",
+                URLUtil.cleanGoogleSearchURL("https://google.de/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0CCEQFjAAahUKEwjJurHd2sfHAhWBsxQKHSrEAaM&url=https%3A%2F%2Fmoz.com%2Fugc%2Fthe-ultimate-guide-to-the-google-search-parameters&ei=0THeVYmOJIHnUqqIh5gK&usg=AFQjCNHnid_r_d2LP8_MqvI7lQnTC3lB_g&sig2=ICzxDroG2ENTJSUGmdhI2w"));
+        // foreign domain
+        assertEquals(
+                "https://moz.com/ugc/the-ultimate-guide-to-the-google-search-parameters",
+                URLUtil.cleanGoogleSearchURL("https://www.google.fr/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0CCEQFjAAahUKEwjJurHd2sfHAhWBsxQKHSrEAaM&url=https%3A%2F%2Fmoz.com%2Fugc%2Fthe-ultimate-guide-to-the-google-search-parameters&ei=0THeVYmOJIHnUqqIh5gK&usg=AFQjCNHnid_r_d2LP8_MqvI7lQnTC3lB_g&sig2=ICzxDroG2ENTJSUGmdhI2w"));
+        // foreign domain co.uk
+        assertEquals(
+                "https://moz.com/ugc/the-ultimate-guide-to-the-google-search-parameters",
+                URLUtil.cleanGoogleSearchURL("https://www.google.co.uk/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0CCEQFjAAahUKEwjJurHd2sfHAhWBsxQKHSrEAaM&url=https%3A%2F%2Fmoz.com%2Fugc%2Fthe-ultimate-guide-to-the-google-search-parameters&ei=0THeVYmOJIHnUqqIh5gK&usg=AFQjCNHnid_r_d2LP8_MqvI7lQnTC3lB_g&sig2=ICzxDroG2ENTJSUGmdhI2w"));
+        // accept ftp results
+        assertEquals(
+                "ftp://moz.com/ugc/the-ultimate-guide-to-the-google-search-parameters",
+                URLUtil.cleanGoogleSearchURL("https://www.google.fr/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0CCEQFjAAahUKEwjJurHd2sfHAhWBsxQKHSrEAaM&url=ftp%3A%2F%2Fmoz.com%2Fugc%2Fthe-ultimate-guide-to-the-google-search-parameters&ei=0THeVYmOJIHnUqqIh5gK&usg=AFQjCNHnid_r_d2LP8_MqvI7lQnTC3lB_g&sig2=ICzxDroG2ENTJSUGmdhI2w"));
+    }
+
+    @Test
+    void isURLshouldAcceptValidURL() {
+        assertTrue(URLUtil.isURL("http://www.google.com"));
+        assertTrue(URLUtil.isURL("https://www.google.com"));
+    }
+
+    @Test
+    void isURLshouldRejectInvalidURL() {
+        assertFalse(URLUtil.isURL("www.google.com"));
+        assertFalse(URLUtil.isURL("google.com"));
+    }
+
+    @Test
+    void isURLshouldRejectEmbeddedURL() {
+        boolean result = URLUtil.isURL("dblp computer science bibliography, http://dblp.org");
+        assertEquals(false, result);
+    }
+
+    @Test
+    void createUriShouldHandlePipeCharacter() {
+        String input = "http://example.com/test|file";
+        URI uri = URLUtil.createUri(input);
+        assertEquals("http://example.com/test%7Cfile", uri.toString());
+    }
+
+    @ParameterizedTest
+    @CsvSource({
+    // Relative URLs (should default to HTTPS)
+    "www.example.com, https://www.example.com",
+    "example.com, https://example.com",
+
+    // Absolute URLs (should remain unchanged)
+    "http://www.example.com, http://www.example.com",
+    "https://www.example.com, https://www.example.com"
+    })
+    void createShouldHandleURLs(String expected, String input) throws Exception {
+        URL url = URLUtil.create(input);
+        assertEquals(expected, url.toString());
+    }
+
+    @ParameterizedTest
+    @CsvSource({
+        "ftp://example.com, ftp://example.com",
+        "file:///path/to/file, file:/path/to/file"
+    })
+    void createShouldHandleOtherProtocols(String expectedUrl, String inputUrl) throws Exception {
+        URL actualUrl = URLUtil.create(inputUrl);
+        assertEquals(expectedUrl, actualUrl.toString());
+    }
+}