From b372864029de888933bb6be4293097699acd32a2 Mon Sep 17 00:00:00 2001
From: Kai Yuan <kent.yuan@Gmail.com>
Date: Mon, 11 Jul 2022 04:09:49 +0200
Subject: [PATCH] BAEL-5650 jar file path (#12463)

* BAEL-5650 jar file path

* move to jar module
---
 core-java-modules/core-java-jar/pom.xml       |  9 ++-
 .../baeldung/jarfile/JarFilePathResolver.java | 42 ++++++++++++++
 .../jarfile/JarFilePathResolverUnitTest.java  | 55 +++++++++++++++++++
 core-java-modules/core-java-lang-5/pom.xml    |  4 +-
 4 files changed, 106 insertions(+), 4 deletions(-)
 create mode 100644 core-java-modules/core-java-jar/src/main/java/com/baeldung/jarfile/JarFilePathResolver.java
 create mode 100644 core-java-modules/core-java-jar/src/test/java/com/baeldung/jarfile/JarFilePathResolverUnitTest.java

diff --git a/core-java-modules/core-java-jar/pom.xml b/core-java-modules/core-java-jar/pom.xml
index 19da9b8a56..c56fcbd8b5 100644
--- a/core-java-modules/core-java-jar/pom.xml
+++ b/core-java-modules/core-java-jar/pom.xml
@@ -54,6 +54,12 @@
             <artifactId>moneta</artifactId>
             <version>${javamoney.moneta.version}</version>
         </dependency>
+        <dependency>
+            <groupId>org.mockito</groupId>
+            <artifactId>mockito-junit-jupiter</artifactId>
+            <version>${mockito.version}</version>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
 
     <build>
@@ -266,6 +272,7 @@
         <!-- util -->
         <unix4j.version>0.4</unix4j.version>
         <grep4j.version>1.8.7</grep4j.version>
+        <mockito.version>4.6.1</mockito.version>
         <!-- maven plugins -->
         <javamoney.moneta.version>1.1</javamoney.moneta.version>
         <maven-javadoc-plugin.version>3.0.0-M1</maven-javadoc-plugin.version>
@@ -279,4 +286,4 @@
         <target.version>1.8</target.version>
     </properties>
 
-</project>
\ No newline at end of file
+</project>
diff --git a/core-java-modules/core-java-jar/src/main/java/com/baeldung/jarfile/JarFilePathResolver.java b/core-java-modules/core-java-jar/src/main/java/com/baeldung/jarfile/JarFilePathResolver.java
new file mode 100644
index 0000000000..3dab91f31a
--- /dev/null
+++ b/core-java-modules/core-java-jar/src/main/java/com/baeldung/jarfile/JarFilePathResolver.java
@@ -0,0 +1,42 @@
+package com.baeldung.jarfile;
+
+import java.net.URISyntaxException;
+import java.net.URL;
+import java.nio.file.Paths;
+
+public class JarFilePathResolver {
+
+    public String getJarFilePath(Class clazz) {
+        try {
+            return byGetProtectionDomain(clazz);
+        } catch (Exception e) {
+            // cannot get jar file path using byGetProtectionDomain
+            // Exception handling omitted
+        }
+        return byGetResource(clazz);
+    }
+
+    String byGetProtectionDomain(Class clazz) throws URISyntaxException {
+        URL url = clazz.getProtectionDomain().getCodeSource().getLocation();
+        return Paths.get(url.toURI()).toString();
+    }
+
+    String byGetResource(Class clazz) {
+        final URL classResource = clazz.getResource(clazz.getSimpleName() + ".class");
+        if (classResource == null) {
+            throw new RuntimeException("class resource is null");
+        }
+
+        final String url = classResource.toString();
+        if (url.startsWith("jar:file:")) {
+            // extract 'file:......jarName.jar' part from the url string
+            String path = url.replaceAll("^jar:(file:.*[.]jar)!/.*", "$1");
+            try {
+                return Paths.get(new URL(path).toURI()).toString();
+            } catch (Exception e) {
+                throw new RuntimeException("Invalid Jar File URL String");
+            }
+        }
+        throw new RuntimeException("Invalid Jar File URL String");
+    }
+}
diff --git a/core-java-modules/core-java-jar/src/test/java/com/baeldung/jarfile/JarFilePathResolverUnitTest.java b/core-java-modules/core-java-jar/src/test/java/com/baeldung/jarfile/JarFilePathResolverUnitTest.java
new file mode 100644
index 0000000000..ad84bd9379
--- /dev/null
+++ b/core-java-modules/core-java-jar/src/test/java/com/baeldung/jarfile/JarFilePathResolverUnitTest.java
@@ -0,0 +1,55 @@
+package com.baeldung.jarfile;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+import com.google.common.base.Ascii;
+import java.io.File;
+import java.net.URISyntaxException;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.Spy;
+import org.mockito.junit.jupiter.MockitoExtension;
+
+@ExtendWith(MockitoExtension.class)
+class JarFilePathResolverUnitTest {
+    @Spy
+    JarFilePathResolver jarFilePathResolver;
+
+    @Test
+    void givenClassObjectWhenCallingByGetProtectionDomainShouldGetExpectedPath() throws Exception {
+        String jarPath = jarFilePathResolver.byGetProtectionDomain(Ascii.class);
+        assertThat(jarPath).endsWith(".jar").contains("guava");
+        assertThat(new File(jarPath)).exists();
+    }
+
+    @Test
+    void givenClassObjectWhenCallingByGetResourceShouldGetExpectedPath() {
+        String jarPath = jarFilePathResolver.byGetResource(Ascii.class);
+        assertThat(jarPath).endsWith(".jar").contains("guava");
+        assertThat(new File(jarPath)).exists();
+    }
+
+    @Test
+    void givenClassObjectWhenNoSecurityExceptionRaisedShouldGetExpectedPath() throws URISyntaxException {
+        String jarPath = jarFilePathResolver.getJarFilePath(Ascii.class);
+        assertThat(jarPath).endsWith(".jar").contains("guava");
+        assertThat(new File(jarPath)).exists();
+        verify(jarFilePathResolver, times(1)).byGetProtectionDomain(Ascii.class);
+        verify(jarFilePathResolver, never()).byGetResource(Ascii.class);
+    }
+
+    @Test
+    void givenClassObjectWhenSecurityExceptionRaisedShouldGetExpectedPath() throws URISyntaxException {
+        when(jarFilePathResolver.byGetProtectionDomain(Ascii.class)).thenThrow(new SecurityException("not allowed"));
+        String jarPath = jarFilePathResolver.getJarFilePath(Ascii.class);
+        assertThat(jarPath).endsWith(".jar").contains("guava");
+        assertThat(new File(jarPath)).exists();
+        verify(jarFilePathResolver, times(1)).byGetProtectionDomain(Ascii.class);
+        verify(jarFilePathResolver, times(1)).byGetResource(Ascii.class);
+    }
+
+}
diff --git a/core-java-modules/core-java-lang-5/pom.xml b/core-java-modules/core-java-lang-5/pom.xml
index 6d3771bd31..5255866f03 100644
--- a/core-java-modules/core-java-lang-5/pom.xml
+++ b/core-java-modules/core-java-lang-5/pom.xml
@@ -13,7 +13,6 @@
         <artifactId>core-java-modules</artifactId>
         <version>0.0.1-SNAPSHOT</version>
     </parent>
-
     <build>
         <finalName>core-java-lang-5</finalName>
         <resources>
@@ -23,5 +22,4 @@
             </resource>
         </resources>
     </build>
-
-</project>
\ No newline at end of file
+</project>