Add ClassLoaderUtils.getSystemURLs() and getThreadURLs().

3 files changed, 44 insertions, 4 deletions

diff --git a/src/changes/changes.xml b/src/changes/changes.xml
index 34e5c9aec..e12e39408 100644
--- a/src/changes/changes.xml
+++ b/src/changes/changes.xml
@@ -188,6 +188,7 @@ The <action> type attribute can be add,update,fix,remove.
     <action                   type="add" dev="ggregory" due-to="Arturo Bernal">Add CalendarUtils#getDayOfYear() #968</action>
     <action                   type="add" dev="ggregory" due-to="Gary Gregory">Add NumberRange, DoubleRange, IntegerRange, LongRange.</action>
     <action                   type="add" dev="ggregory" due-to="Diego Marcilio, Bruno P. Kinoshita, Gary Gregory">Add missing exception javadoc/tests for some null arguments #869.</action>
+    <action                   type="add" dev="ggregory" due-to="Gary Gregory">Add ClassLoaderUtils.getSystemURLs() and getThreadURLs().</action>
     <!-- UPDATE -->
     <action                   type="update" dev="ggregory" due-to="Dependabot, XenoAmess, Gary Gregory">Bump actions/cache from 2.1.4 to 3.0.10 #742, #752, #764, #833, #867, #959, #964.</action>
     <action                   type="update" dev="ggregory" due-to="Dependabot, Gary Gregory">Bump actions/checkout from 2 to 3.1.0 #819, #825, #859, #963.</action>
diff --git a/src/main/java/org/apache/commons/lang3/ClassLoaderUtils.java b/src/main/java/org/apache/commons/lang3/ClassLoaderUtils.java
index a87156a08..dda4828a2 100644
--- a/src/main/java/org/apache/commons/lang3/ClassLoaderUtils.java
+++ b/src/main/java/org/apache/commons/lang3/ClassLoaderUtils.java
@@ -17,6 +17,7 @@
 
 package org.apache.commons.lang3;
 
+import java.net.URL;
 import java.net.URLClassLoader;
 import java.util.Arrays;
 
@@ -27,6 +28,32 @@ import java.util.Arrays;
  */
 public class ClassLoaderUtils {
 
+    private static final URL[] EMPTY_URL_ARRAY = new URL[] {};
+
+    /**
+     * Gets the system class loader's URLs, if any.
+     *
+     * @return the system class loader's URLs, if any.
+     * @since 3.13.0
+     */
+    public static URL[] getSystemURLs() {
+        return getURLs(ClassLoader.getSystemClassLoader());
+    }
+
+    /**
+     * Gets the current thread's context class loader's URLs, if any.
+     *
+     * @return the current thread's context class loader's URLs, if any.
+     * @since 3.13.0
+     */
+    public static URL[] getThreadURLs() {
+        return getURLs(Thread.currentThread().getContextClassLoader());
+    }
+
+    private static URL[] getURLs(final ClassLoader cl) {
+        return cl instanceof URLClassLoader ? ((URLClassLoader) cl).getURLs() : EMPTY_URL_ARRAY;
+    }
+
     /**
      * Converts the given class loader to a String calling {@link #toString(URLClassLoader)}.
      *
@@ -41,8 +68,7 @@ public class ClassLoaderUtils {
     }
 
     /**
-     * Converts the given URLClassLoader to a String in the format
-     * {@code "URLClassLoader.toString() + [URL1, URL2, ...]"}.
+     * Converts the given URLClassLoader to a String in the format {@code "URLClassLoader.toString() + [URL1, URL2, ...]"}.
      *
      * @param classLoader to URLClassLoader to convert.
      * @return the formatted string.
diff --git a/src/test/java/org/apache/commons/lang3/ClassLoaderUtilsTest.java b/src/test/java/org/apache/commons/lang3/ClassLoaderUtilsTest.java
index ea56f50c8..b51ed3635 100644
--- a/src/test/java/org/apache/commons/lang3/ClassLoaderUtilsTest.java
+++ b/src/test/java/org/apache/commons/lang3/ClassLoaderUtilsTest.java
@@ -17,6 +17,8 @@
 
 package org.apache.commons.lang3;
 
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+
 import java.io.IOException;
 import java.net.URL;
 import java.net.URLClassLoader;
@@ -30,6 +32,18 @@ import org.junit.jupiter.api.Test;
 public class ClassLoaderUtilsTest extends AbstractLangTest {
 
     @Test
+    public void testGetSystemURLs() {
+        // TODO How to better test considering this test may be called from an IDE and Maven?
+        assertNotNull(ClassLoaderUtils.getSystemURLs());
+    }
+
+    @Test
+    public void testGetThreadURLs() {
+        // TODO How to better test considering this test may be called from an IDE and Maven?
+        assertNotNull(ClassLoaderUtils.getThreadURLs());
+    }
+
+    @Test
     public void testToString_ClassLoader() throws IOException {
         final URL url = new URL("http://localhost");
         try (URLClassLoader urlClassLoader = new URLClassLoader(new URL[] { url })) {
@@ -43,8 +57,7 @@ public class ClassLoaderUtilsTest extends AbstractLangTest {
     public void testToString_URLClassLoader() throws IOException {
         final URL url = new URL("http://localhost");
         try (URLClassLoader urlClassLoader = new URLClassLoader(new URL[] { url })) {
-            Assertions.assertEquals(String.format("%s[%s]", urlClassLoader, url),
-                    ClassLoaderUtils.toString(urlClassLoader));
+            Assertions.assertEquals(String.format("%s[%s]", urlClassLoader, url), ClassLoaderUtils.toString(urlClassLoader));
         }
     }
 }