Avoid parsing nested jar URLs for cached resource lookups

loader/spring-boot-loader/src/main/java/org/springframework/boot/loader/net/protocol/jar/JarFileUrlKey.java

@@ -44,6 +44,14 @@ final class JarFileUrlKey {
 		this.runtimeRef = "runtime".equals(url.getRef());
 	}
 
+	JarFileUrlKey(String protocol, String host, int port, String file, boolean runtimeRef) {
+		this.protocol = protocol;
+		this.host = host;
+		this.port = port;
+		this.file = file;
+		this.runtimeRef = runtimeRef;
+	}
+
 	@Override
 	public boolean equals(Object obj) {
 		if (this == obj) {

loader/spring-boot-loader/src/main/java/org/springframework/boot/loader/net/protocol/jar/JarUrlConnection.java

@@ -45,6 +45,7 @@
  * @author Phillip Webb
  * @author Andy Wilkinson
  * @author Rostyslav Dudka
+ * @author Sharan Bharmshetty
  */
 final class JarUrlConnection extends java.net.JarURLConnection {
 
@@ -335,15 +336,12 @@ static JarUrlConnection open(URL url) throws IOException {
 		String spec = url.getFile();
 		if (spec.startsWith("nested:")) {
 			int separator = spec.indexOf("!/");
-			boolean specHasEntry = (separator != -1) && (separator + 2 != spec.length());
-			if (specHasEntry) {
-				URL jarFileUrl = new URL(spec.substring(0, separator));
-				if ("runtime".equals(url.getRef())) {
-					jarFileUrl = new URL(jarFileUrl, "#runtime");
-				}
+			boolean specHasJarEntry = (separator != -1) && (separator + 2 != spec.length());
+			if (specHasJarEntry) {
+				String jarFileSpec = spec.substring(0, separator);
+				boolean runtimeRef = "runtime".equals(url.getRef());
+				JarFile jarFile = jarFiles.getOrCreateAndCache(jarFileSpec, runtimeRef);
 				String entryName = UrlDecoder.decode(spec.substring(separator + 2));
-				JarFile jarFile = jarFiles.getOrCreate(true, jarFileUrl);
-				jarFiles.cacheIfAbsent(true, jarFileUrl, jarFile);
 				if (!hasEntry(jarFile, entryName)) {
 					return notFoundConnection(jarFile.getName(), entryName);
 				}

loader/spring-boot-loader/src/main/java/org/springframework/boot/loader/net/protocol/jar/UrlJarFiles.java

@@ -31,6 +31,7 @@
  * instances.
  *
  * @author Phillip Webb
+ * @author Sharan Bharmshetty
  */
 class UrlJarFiles {
 
@@ -53,6 +54,20 @@ class UrlJarFiles {
 		this.factory = factory;
 	}
 
+	JarFile getOrCreateAndCache(String jarFileSpec, boolean runtimeRef) throws IOException {
+		JarFileUrlKey jarFileUrlKey = new JarFileUrlKey("jar", "", -1, jarFileSpec, runtimeRef);
+		JarFile jarFile = this.cache.get(jarFileUrlKey);
+		if (jarFile == null) {
+			URL jarFileUrl = new URL(jarFileSpec);
+			if (runtimeRef) {
+				jarFileUrl = new URL(jarFileUrl, "#runtime");
+			}
+			jarFile = this.factory.createJarFile(jarFileUrl, this::onClose);
+			this.cache.putIfAbsent(jarFileUrlKey, jarFile, jarFileUrl);
+		}
+		return jarFile;
+	}
+
 	/**
 	 * Get an existing {@link JarFile} instance from the cache, or create a new
 	 * {@link JarFile} instance that can be {@link #cacheIfAbsent(boolean, URL, JarFile)
@@ -154,9 +169,17 @@ private static final class Cache {
 		 * @return the cached {@link JarFile} or {@code null}
 		 */
 		JarFile get(URL jarFileUrl) {
-			JarFileUrlKey urlKey = new JarFileUrlKey(jarFileUrl);
+			return get(new JarFileUrlKey(jarFileUrl));
+		}
+
+		/**
+		 * Get a {@link JarFile} from the cache given a jar file URL key.
+		 * @param jarFileUrlKey the jar file URL key
+		 * @return the cached {@link JarFile} or {@code null}
+		 */
+		JarFile get(JarFileUrlKey jarFileUrlKey) {
 			synchronized (this) {
-				return this.jarFileUrlToJarFile.get(urlKey);
+				return this.jarFileUrlToJarFile.get(jarFileUrlKey);
 			}
 		}
 
@@ -180,11 +203,23 @@ URL get(JarFile jarFile) {
 		 * they were already there
 		 */
 		boolean putIfAbsent(URL jarFileUrl, JarFile jarFile) {
-			JarFileUrlKey urlKey = new JarFileUrlKey(jarFileUrl);
+			return putIfAbsent(new JarFileUrlKey(jarFileUrl), jarFile, jarFileUrl);
+		}
+
+		/**
+		 * Put the given jar file URL and jar file into the cache if they aren't already
+		 * there.
+		 * @param jarFileUrlKey the jar file URL key
+		 * @param jarFileUrl the jar file URL
+		 * @param jarFile the jar file
+		 * @return {@code true} if the items were added to the cache or {@code false} if
+		 * they were already there
+		 */
+		boolean putIfAbsent(JarFileUrlKey jarFileUrlKey, JarFile jarFile, URL jarFileUrl) {
 			synchronized (this) {
-				JarFile cached = this.jarFileUrlToJarFile.get(urlKey);
+				JarFile cached = this.jarFileUrlToJarFile.get(jarFileUrlKey);
 				if (cached == null) {
-					this.jarFileUrlToJarFile.put(urlKey, jarFile);
+					this.jarFileUrlToJarFile.put(jarFileUrlKey, jarFile);
 					this.jarFileToJarFileUrl.put(jarFile, jarFileUrl);
 					return true;
 				}

loader/spring-boot-loader/src/test/java/org/springframework/boot/loader/net/protocol/jar/JarFileUrlKeyTests.java

@@ -30,6 +30,7 @@
  * Tests for {@link JarFileUrlKey}.
  *
  * @author Phillip Webb
+ * @author Sharan Bharmshetty
  */
 class JarFileUrlKeyTests {
 
@@ -101,4 +102,27 @@ private JarFileUrlKey key(String spec) throws MalformedURLException {
 		return new JarFileUrlKey(new URL(spec));
 	}
 
+	@Test
+	void directKeyEqualsUrlKey() throws Exception {
+		JarFileUrlKey fromUrl = key("jar:nested:/my.jar/!mynested.jar!/my/path");
+		JarFileUrlKey direct = new JarFileUrlKey("jar", "", -1, "nested:/my.jar/!mynested.jar!/my/path", false);
+		assertThat(direct).isEqualTo(fromUrl);
+		assertThat(direct.hashCode()).isEqualTo(fromUrl.hashCode());
+	}
+
+	@Test
+	void directKeyWithRuntimeRefEqualsUrlKey() throws Exception {
+		JarFileUrlKey fromUrl = key("jar:nested:/my.jar/!mynested.jar!/my/path#runtime");
+		JarFileUrlKey direct = new JarFileUrlKey("jar", "", -1, "nested:/my.jar/!mynested.jar!/my/path", true);
+		assertThat(direct).isEqualTo(fromUrl);
+		assertThat(direct.hashCode()).isEqualTo(fromUrl.hashCode());
+	}
+
+	@Test
+	void directKeyWithRuntimeRefNotEqualToKeyWithout() {
+		JarFileUrlKey k1 = new JarFileUrlKey("jar", "", -1, "nested:/my.jar/!mynested.jar!/my/path", true);
+		JarFileUrlKey k2 = new JarFileUrlKey("jar", "", -1, "nested:/my.jar/!mynested.jar!/my/path", false);
+		assertThat(k1).isNotEqualTo(k2);
+	}
+
 }