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diff --git a/src/main/java/org/apache/commons/lang3/ClassPathUtils.java b/src/main/java/org/apache/commons/lang3/ClassPathUtils.java
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+++ b/src/main/java/org/apache/commons/lang3/ClassPathUtils.java
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+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+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>
+ *
+ * @since 3.3
+ */
+//@Immutable
+public class ClassPathUtils {
+
+    /**
+     * Converts a package name to a Java path ('/').
+     *
+     * @param path the source path.
+     * @return a package name.
+     * @since 3.13.0
+     */
+    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>
+     *
+     * <pre>
+     * ClassPathUtils.toFullyQualifiedName(StringUtils.class, "StringUtils.properties") = "org.apache.commons.lang3.StringUtils.properties"
+     * </pre>
+     *
+     * @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) {
+        Objects.requireNonNull(context, "context");
+        Objects.requireNonNull(resourceName, "resourceName");
+        return toFullyQualifiedName(context.getPackage(), resourceName);
+    }
+
+    /**
+     * 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>
+     *
+     * <pre>
+     * ClassPathUtils.toFullyQualifiedName(StringUtils.class.getPackage(), "StringUtils.properties") = "org.apache.commons.lang3.StringUtils.properties"
+     * </pre>
+     *
+     * @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) {
+        Objects.requireNonNull(context, "context");
+        Objects.requireNonNull(resourceName, "resourceName");
+        return context.getName() + "." + 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>
+     *
+     * <pre>
+     * ClassPathUtils.toFullyQualifiedPath(StringUtils.class, "StringUtils.properties") = "org/apache/commons/lang3/StringUtils.properties"
+     * </pre>
+     *
+     * @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) {
+        Objects.requireNonNull(context, "context");
+        Objects.requireNonNull(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>
+     *
+     * <pre>
+     * ClassPathUtils.toFullyQualifiedPath(StringUtils.class.getPackage(), "StringUtils.properties") = "org/apache/commons/lang3/StringUtils.properties"
+     * </pre>
+     *
+     * @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) {
+        Objects.requireNonNull(context, "context");
+        Objects.requireNonNull(resourceName, "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() {
+    }
+
+}