Add ClassPathUtils.packageToPath(String) and pathToPackage(String)

src/changes/changes.xml

@@ -179,6 +179,7 @@ The <action> type attribute can be add,update,fix,remove.
     <action                   type="add" dev="ggregory" due-to="Gary Gregory">Add Processor.toString().</action>
     <action                   type="add" dev="ggregory" due-to="Gary Gregory">Add HashCodeBuilder.equals(Object).</action>
     <action                   type="add" dev="ggregory" due-to="Gary Gregory">Add BooleanUtils.values() and forEach().</action>
+    <action                   type="add" dev="ggregory" due-to="Gary Gregory">Add ClassPathUtils.packageToPath(String) and pathToPackage(String)</action>
     <!-- UPDATE -->
     <action                   type="update" dev="ggregory" due-to="Dependabot, XenoAmess, Gary Gregory">Bump actions/cache from 2.1.4 to 3.0.9 #742, #752, #764, #833, #867, #959.</action>
     <action                   type="update" dev="ggregory" due-to="Dependabot, Gary Gregory">Bump actions/checkout from 2 to 3.0.2 #819, #825, #859.</action>

src/main/java/org/apache/commons/lang3/ClassPathUtils.java

@@ -16,10 +16,14 @@
  */
 package org.apache.commons.lang3;
 
+import java.util.Objects;
+
 /**
  * Operations regarding the classpath.
  *
- * <p>The methods of this class do not allow {@code null} inputs.</p>
+ * <p>
+ * The methods of this class do not allow {@code null} inputs.
+ * </p>
  *
  * @since 3.3
  */
@@ -27,34 +31,45 @@
 public class ClassPathUtils {
 
     /**
-     * {@link ClassPathUtils} instances should NOT be constructed in
-     * standard programming. Instead, the class should be used as
-     * {@code ClassPathUtils.toFullyQualifiedName(MyClass.class, "MyClass.properties");}.
+     * Converts a package name to a Java path ('/').
      *
-     * <p>This constructor is public to permit tools that require a JavaBean
-     * instance to operate.</p>
+     * @param path the source path.
+     * @return a package name.
+     * @since 3.13.0
      */
-    public ClassPathUtils() {
+    public static String packageToPath(final String path) {
+        return Objects.requireNonNull(path, "path").replace('.', '/');
+    }
+
+    /**
+     * Converts a Java path ('/') to a package name.
+     *
+     * @param path the source path.
+     * @return a package name.
+     * @since 3.13.0
+     */
+    public static String pathToPackage(final String path) {
+        return Objects.requireNonNull(path, "path").replace('/', '.');
     }
 
     /**
      * Returns the fully qualified name for the resource with name {@code resourceName} relative to the given context.
      *
-     * <p>Note that this method does not check whether the resource actually exists.
-     * It only constructs the name.
-     * Null inputs are not allowed.</p>
+     * <p>
+     * Note that this method does not check whether the resource actually exists. It only constructs the name. Null inputs are not allowed.
+     * </p>
      *
      * <pre>
      * ClassPathUtils.toFullyQualifiedName(StringUtils.class, "StringUtils.properties") = "org.apache.commons.lang3.StringUtils.properties"
      * </pre>
      *
-     * @param context The context for constructing the name.
+     * @param context      The context for constructing the name.
      * @param resourceName the resource name to construct the fully qualified name for.
      * @return the fully qualified name of the resource with name {@code resourceName}.
      * @throws NullPointerException if either {@code context} or {@code resourceName} is null.
      */
     public static String toFullyQualifiedName(final Class<?> context, final String resourceName) {
-        Validate.notNull(context, "context" );
+        Validate.notNull(context, "context");
         Validate.notNull(resourceName, "resourceName");
         return toFullyQualifiedName(context.getPackage(), resourceName);
     }
@@ -62,21 +77,21 @@ public static String toFullyQualifiedName(final Class<?> context, final String r
     /**
      * Returns the fully qualified name for the resource with name {@code resourceName} relative to the given context.
      *
-     * <p>Note that this method does not check whether the resource actually exists.
-     * It only constructs the name.
-     * Null inputs are not allowed.</p>
+     * <p>
+     * Note that this method does not check whether the resource actually exists. It only constructs the name. Null inputs are not allowed.
+     * </p>
      *
      * <pre>
      * ClassPathUtils.toFullyQualifiedName(StringUtils.class.getPackage(), "StringUtils.properties") = "org.apache.commons.lang3.StringUtils.properties"
      * </pre>
      *
-     * @param context The context for constructing the name.
+     * @param context      The context for constructing the name.
      * @param resourceName the resource name to construct the fully qualified name for.
      * @return the fully qualified name of the resource with name {@code resourceName}.
      * @throws NullPointerException if either {@code context} or {@code resourceName} is null.
      */
     public static String toFullyQualifiedName(final Package context, final String resourceName) {
-        Validate.notNull(context, "context" );
+        Validate.notNull(context, "context");
         Validate.notNull(resourceName, "resourceName");
         return context.getName() + "." + resourceName;
     }
@@ -84,46 +99,56 @@ public static String toFullyQualifiedName(final Package context, final String re
     /**
      * Returns the fully qualified path for the resource with name {@code resourceName} relative to the given context.
      *
-     * <p>Note that this method does not check whether the resource actually exists.
-     * It only constructs the path.
-     * Null inputs are not allowed.</p>
+     * <p>
+     * Note that this method does not check whether the resource actually exists. It only constructs the path. Null inputs are not allowed.
+     * </p>
      *
      * <pre>
      * ClassPathUtils.toFullyQualifiedPath(StringUtils.class, "StringUtils.properties") = "org/apache/commons/lang3/StringUtils.properties"
      * </pre>
      *
-     * @param context The context for constructing the path.
+     * @param context      The context for constructing the path.
      * @param resourceName the resource name to construct the fully qualified path for.
      * @return the fully qualified path of the resource with name {@code resourceName}.
      * @throws NullPointerException if either {@code context} or {@code resourceName} is null.
      */
     public static String toFullyQualifiedPath(final Class<?> context, final String resourceName) {
-        Validate.notNull(context, "context" );
+        Validate.notNull(context, "context");
         Validate.notNull(resourceName, "resourceName");
         return toFullyQualifiedPath(context.getPackage(), resourceName);
     }
 
-
     /**
      * Returns the fully qualified path for the resource with name {@code resourceName} relative to the given context.
      *
-     * <p>Note that this method does not check whether the resource actually exists.
-     * It only constructs the path.
-     * Null inputs are not allowed.</p>
+     * <p>
+     * Note that this method does not check whether the resource actually exists. It only constructs the path. Null inputs are not allowed.
+     * </p>
      *
      * <pre>
      * ClassPathUtils.toFullyQualifiedPath(StringUtils.class.getPackage(), "StringUtils.properties") = "org/apache/commons/lang3/StringUtils.properties"
      * </pre>
      *
-     * @param context The context for constructing the path.
+     * @param context      The context for constructing the path.
      * @param resourceName the resource name to construct the fully qualified path for.
      * @return the fully qualified path of the resource with name {@code resourceName}.
      * @throws NullPointerException if either {@code context} or {@code resourceName} is null.
      */
     public static String toFullyQualifiedPath(final Package context, final String resourceName) {
-        Validate.notNull(context, "context" );
+        Validate.notNull(context, "context");
         Validate.notNull(resourceName, "resourceName");
-        return context.getName().replace('.', '/') + "/" + resourceName;
+        return packageToPath(context.getName()) + "/" + resourceName;
+    }
+
+    /**
+     * {@link ClassPathUtils} instances should NOT be constructed in standard programming. Instead, the class should be used as
+     * {@code ClassPathUtils.toFullyQualifiedName(MyClass.class, "MyClass.properties");}.
+     *
+     * <p>
+     * This constructor is public to permit tools that require a JavaBean instance to operate.
+     * </p>
+     */
+    public ClassPathUtils() {
     }
 
 }

src/test/java/org/apache/commons/lang3/ClassPathUtilsTest.java

@@ -41,6 +41,20 @@ public void testConstructor() {
         assertFalse(Modifier.isFinal(ClassPathUtils.class.getModifiers()));
     }
 
+    @Test
+    public void testPackageToPath() {
+        assertEquals("a", ClassPathUtils.packageToPath("a"));
+        assertEquals("a/b", ClassPathUtils.packageToPath("a.b"));
+        assertEquals("a/b/c", ClassPathUtils.packageToPath("a.b.c"));
+    }
+
+    @Test
+    public void testPathToPackage() {
+        assertEquals("a", ClassPathUtils.pathToPackage("a"));
+        assertEquals("a.b", ClassPathUtils.pathToPackage("a/b"));
+        assertEquals("a.b.c", ClassPathUtils.pathToPackage("a/b/c"));
+    }
+
     @Test
     public void testToFullyQualifiedNameNullClassString() {
         assertThrows(NullPointerException.class,