yegor256 · PeJetuz · Jan 21, 2025 · Jan 28, 2025 · Jan 30, 2025
diff --git a/pom.xml b/pom.xml
@@ -81,6 +81,10 @@ SOFTWARE.
       <url>https://github.com/yegor256/cactoos</url>
     </site>
   </distributionManagement>
+  <properties>
+    <testLibPath>src/test/test-lib</testLibPath>
+    <testLibJarPath>${project.build.directory}/${project.artifactId}-test-lib-${project.version}.jar</testLibJarPath>
+  </properties>
   <dependencies>
     <dependency>
       <groupId>org.takes</groupId>
@@ -144,6 +148,10 @@ SOFTWARE.
               <threads>8</threads>
               <mutationThreshold>75</mutationThreshold>
               <timeoutConstant>500</timeoutConstant>
+              <additionalClasspathElements>
+                <additionalClasspathElement>${testLibJarPath}</additionalClasspathElement>
+              </additionalClasspathElements>
+              <useClasspathJar>true</useClasspathJar>
             </configuration>
           </execution>
         </executions>
@@ -172,6 +180,59 @@ SOFTWARE.
           </execution>
         </executions>
       </plugin>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+    
8000
    <artifactId>maven-surefire-plugin</artifactId>
+        <configuration>
+          <additionalClasspathDependencies>
+            <additionalClasspathDependency>
+              <groupId>org.cactoos</groupId>
+              <artifactId>${project.artifactId}-test-lib</artifactId>
+              <version>${project.version}</version>
+            </additionalClasspathDependency>
+          </additionalClasspathDependencies>
+        </configuration>
+      </plugin>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-assembly-plugin</artifactId>
+        <executions>
+          <execution>
+            <id>make-test-lib</id>
+            <phase>initialize</phase>
+            <goals>
+              <goal>single</goal>
+            </goals>
+            <configuration>
+              <finalName>${project.artifactId}-test-lib-${project.version}</finalName>
+              <descriptors>
+                <descriptor>${testLibPath}/assembly.xml</descriptor>
+              </descriptors>
+              <appendAssemblyId>false</appendAssemblyId>
+            </configuration>
+          </execution>
+        </executions>
+      </plugin>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-install-plugin</artifactId>
+        <executions>
+          <execution>
+            <id>make-test-lib</id>
+            <phase>initialize</phase>
+            <goals>
+              <goal>install-file</goal>
+            </goals>
+            <configuration>
+              <file>${testLibJarPath}</file>
+              <groupId>org.cactoos</groupId>
+              <artifactId>${project.artifactId}-test-lib</artifactId>
+              <version>${project.version}</version>
+              <packaging>jar</packaging>
+            </configuration>
+          </execution>
+        </executions>
+      </plugin>
       <plugin>
         <groupId>org.jacoco</groupId>
         <artifactId>jacoco-maven-plugin</artifactId>

diff --git a/src/main/java/org/cactoos/io/ResourceOf.java b/src/main/java/org/cactoos/io/ResourceOf.java
@@ -25,6 +25,12 @@
 
 import java.io.IOException;
 import java.io.InputStream;
+import java.net.URISyntaxException;
+import java.net.URL;
+import java.nio.charset.StandardCharsets;
+import java.util.jar.JarEntry;
+import java.util.jar.JarFile;
+import java.util.stream.Collectors;
 import org.cactoos.Func;
 import org.cactoos.Input;
 import org.cactoos.Text;
@@ -225,10 +231,18 @@ public InputStream stream() throws Exception {
                 "The \"classloader\" is NULL, which is not allowed"
             );
         }
-        InputStream input = this.loader.getResourceAsStream(
-            this.path.asString()
-        );
-        if (input == null) {
+        final InputStream input;
+        final String pth = this.path.asString();
+        final URL resource = this.loader.getResource(pth);
+        if (pth.endsWith("/")
+            && resource != null
+            && "jar".equals(resource.getProtocol())
+        ) {
+            input = new JarDirectoryFileNameStream(resource, pth)
+                .files();
+        } else if (resource != null) {
+            input = resource.openStream();
+        } else {
             if (this.fallback == null) {
                 throw new IllegalArgumentException(
                     "The \"fallback\" is NULL, which is not allowed"
@@ -240,4 +254,68 @@ public InputStream stream() throws Exception {
         }
         return input;
     }
+
+    /**
+     * Class for creating a stream of file names from a directory to a jar.
+     *
+     * @since 0.56.2
+     */
+    private static final class JarDirectoryFileNameStream {
+
+        /**
+         * URL of the jar file.
+         */
+        private final URL url;
+
+        /**
+         * Path to the directory in the jar file.
+         */
+        private final String path;
+
+        /**
+         * Ctor.
+         *
+         * @param jarurl URL of the jar file.
+         * @param pth The directory for which we want to get a list of files.
+         */
+        JarDirectoryFileNameStream(final URL jarurl, final String pth) {
+            this.url = jarurl;
+            this.path = pth;
+        }
+
+        /**
+         * Create InputStream of file names from directory to jar.
+         *
+         * @return Stream with file names.
+         * @throws Exception If something goes wrong
+         */
+        public InputStream files() throws Exception {
+            try (JarFile jar = new JarFile(this.extract())) {
+                return new InputStreamOf(
+                    jar
+                        .stream()
+                        .map(JarEntry::getName)
+                        .filter(
+                            name -> !this.path.equals(name)
+                                && name.lastIndexOf(this.path) >= 0
+                        )
+                        .map(name -> name.substring(this.path.length()))
+                        .collect(Collectors.joining("\n"))
+                        .getBytes(StandardCharsets.UTF_8)
+                    );
+            }
+        }
+
+        /**
+         * Extracts the path to a jar file from a URL.
+         *
+         * @return Path to jar file.
+         * @throws URISyntaxException If this URL cannot be converted to a URI.
+         */
+        private String extract() throws URISyntaxException {
+            final String fullpath = this.url.toURI().getSchemeSpecificPart();
+            final int idx = fullpath.indexOf("!/");
+            return fullpath.substring("file:".length(), idx);
+        }
+    }
 }
diff --git a/src/test/java/org/cactoos/io/ResourceOfTest.java b/src/test/java/org/cactoos/io/ResourceOfTest.java
@@ -28,11 +28,13 @@
 import org.cactoos.Text;
 import org.cactoos.bytes.BytesOf;
 import org.cactoos.text.FormattedText;
+import org.cactoos.text.Split;
 import org.cactoos.text.TextOf;
 import org.hamcrest.core.IsEqual;
 import org.junit.jupiter.api.Test;
 import org.llorllale.cactoos.matchers.Assertion;
 import org.llorllale.cactoos.matchers.EndsWith;
+import org.llorllale.cactoos.matchers.HasValues;
 import org.llorllale.cactoos.matchers.StartsWith;
 import org.llorllale.cactoos.matchers.Throws;
 
@@ -42,7 +44,7 @@
  * @since 0.1
  * @checkstyle JavadocMethodCheck (500 lines)
  */
-@SuppressWarnings("PMD.JUnitTestsShouldIncludeAssert")
+@SuppressWarnings({"PMD.JUnitTestsShouldIncludeAssert", "PMD.TooManyMethods"})
 final class ResourceOfTest {
 
     @Test
@@ -113,6 +115,66 @@ void throwsWhenResourceIsAbsent() {
         ).affirm();
     }
 
+    @Test
+    void readTextFromJar() {
+        new Assertion<>(
+            "Can't to read file from jar",
+            new TextOf(
+                new BytesOf(
+                    new ResourceOf(
+                        "org/cactoos/io/small-text-file.txt",
+                        "the replacement"
+                    )
+                )
+            ),
+            new EndsWith("parent directory.")
+        ).affirm();
+    }
+
+    @Test
+    void readDirectoryFromJar() {
+        new Assertion<
1E79
>(
+            "Unable to read file names from jar directory",
+            new Split(
+                new TextOf(
+                    new BytesOf(
+                        new ResourceOf(
+                            "org/cactoos/io/dir/",
+                            "the replacement"
+                        )
+                    )
+                ),
+                new TextOf("\\n")
+            ),
+            new HasValues<>(
+                new TextOf(&q
F438
uot;second-text-file.txt"),
+                new TextOf("small-file-in-dir.txt")
+            )
+        ).affirm();
+    }
+
+    @Test
+    void readDirectory() {
+        new Assertion<>(
+            "Unable to read file names from directory",
+            new Split(
+                new TextOf(
+                    new BytesOf(
+                        new ResourceOf(
+                            "org/cactoos/",
+                            "the replacement"
+                        )
+                    )
+                ),
+                new TextOf("\\n")
+            ),
+            new HasValues<>(
+                new TextOf("digest-calculation.txt"),
+                new TextOf("small-text.txt")
+            )
+        ).affirm();
+    }
+
     @Test
     void acceptsTextAsResourceName() {
         new Assertion<>(

diff --git a/src/test/test-lib/assembly.xml b/src/test/test-lib/assembly.xml
@@ -0,0 +1,42 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+The MIT License (MIT)
+
+Copyright (c) 2017-2025 Yegor Bugayenko
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included
+in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+-->
+<assembly xmlns="http://maven.apache.org/ASSEMBLY/2.2.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/ASSEMBLY/2.2.0 https://maven.apache.org/xsd/assembly-2.2.0.xsd">
+  <id>test-lib</id>
+  <formats>
+    <format>jar</format>
+  </formats>
+  <includeBaseDirectory>false</includeBaseDirectory>
+  <fileSets>
+    <fileSet>
+      <directory>${project.basedir}/${testLibPath}</directory>
+      <outputDirectory>/</outputDirectory>
+      <includes>
+        <include>org/cactoos/io/small-text-file.txt</include>
+        <include>org/cactoos/io/dir/second-text-file.txt</include>
+        <include>org/cactoos/io/dir/small-file-in-dir.txt</include>
+      </includes>
+    </fileSet>
+  </fileSets>
+</assembly>
diff --git a/src/test/test-lib/org/cactoos/io/dir/second-text-file.txt b/src/test/test-lib/org/cactoos/io/dir/second-text-file.txt
@@ -0,0 +1 @@
+Second text file.
diff --git a/src/test/test-lib/org/cactoos/io/dir/small-file-in-dir.txt b/src/test/test-lib/org/cactoos/io/dir/small-file-in-dir.txt
@@ -0,0 +1 @@
+Small file in the directory.
diff --git a/src/test/test-lib/org/cactoos/io/small-text-file.txt b/src/test/test-lib/org/cactoos/io/small-text-file.txt
@@ -0,0 +1 @@
+Small file in the parent directory.