diff --git a/spring-boot-project/spring-boot-tools/spring-boot-loader/src/test/java/org/springframework/boot/loader/jar/HandlerTests.java b/spring-boot-project/spring-boot-tools/spring-boot-loader/src/test/java/org/springframework/boot/loader/jar/HandlerTests.java
index 902aca4212..a7f64895d7 100644
--- a/spring-boot-project/spring-boot-tools/spring-boot-loader/src/test/java/org/springframework/boot/loader/jar/HandlerTests.java
+++ b/spring-boot-project/spring-boot-tools/spring-boot-loader/src/test/java/org/springframework/boot/loader/jar/HandlerTests.java
@@ -156,11 +156,11 @@ class HandlerTests {
 	void fallbackToJdksJarUrlStreamHandler(@TempDir File tempDir) throws Exception {
 		File testJar = new File(tempDir, "test.jar");
 		TestJarCreator.createTestJar(testJar);
-		URLConnection connection = new URL(null, "jar:file:" + testJar.getAbsolutePath() + "!/nested.jar!/",
-				this.handler).openConnection();
+		URLConnection connection = new URL(null, "jar:" + testJar.toURI().toURL() + "!/nested.jar!/", this.handler)
+				.openConnection();
 		assertThat(connection).isInstanceOf(JarURLConnection.class);
 		((JarURLConnection) connection).getJarFile().close();
-		URLConnection jdkConnection = new URL(null, "jar:file:file:" + testJar.getAbsolutePath() + "!/nested.jar!/",
+		URLConnection jdkConnection = new URL(null, "jar:file:" + testJar.toURI().toURL() + "!/nested.jar!/",
 				this.handler).openConnection();
 		assertThat(jdkConnection).isNotInstanceOf(JarURLConnection.class);
 	}
diff --git a/spring-boot-project/spring-boot-tools/spring-boot-loader/src/test/java/org/springframework/boot/loader/jar/JarURLConnectionTests.java b/spring-boot-project/spring-boot-tools/spring-boot-loader/src/test/java/org/springframework/boot/loader/jar/JarURLConnectionTests.java
index be2b51fc09..3b0f777110 100644
--- a/spring-boot-project/spring-boot-tools/spring-boot-loader/src/test/java/org/springframework/boot/loader/jar/JarURLConnectionTests.java
+++ b/spring-boot-project/spring-boot-tools/spring-boot-loader/src/test/java/org/springframework/boot/loader/jar/JarURLConnectionTests.java
@@ -60,7 +60,7 @@ class JarURLConnectionTests {
 
 	@Test
 	void connectionToRootUsingAbsoluteUrl() throws Exception {
-		URL url = new URL("jar:file:" + getAbsolutePath() + "!/");
+		URL url = new URL("jar:" + this.rootJarFile.toURI().toURL() + "!/");
 		assertThat(JarURLConnection.get(url, this.jarFile).getContent()).isSameAs(this.jarFile);
 	}
 
@@ -72,7 +72,7 @@ class JarURLConnectionTests {
 
 	@Test
 	void connectionToEntryUsingAbsoluteUrl() throws Exception {
-		URL url = new URL("jar:file:" + getAbsolutePath() + "!/1.dat");
+		URL url = new URL("jar:" + this.rootJarFile.toURI().toURL() + "!/1.dat");
 		try (InputStream input = JarURLConnection.get(url, this.jarFile).getInputStream()) {
 			assertThat(input).hasSameContentAs(new ByteArrayInputStream(new byte[] { 1 }));
 		}
@@ -88,7 +88,7 @@ class JarURLConnectionTests {
 
 	@Test
 	void connectionToEntryUsingAbsoluteUrlWithFileColonSlashSlashPrefix() throws Exception {
-		URL url = new URL("jar:file:/" + getAbsolutePath() + "!/1.dat");
+		URL url = new URL("jar:" + this.rootJarFile.toURI().toURL() + "!/1.dat");
 		try (InputStream input = JarURLConnection.get(url, this.jarFile).getInputStream()) {
 			assertThat(input).hasSameContentAs(new ByteArrayInputStream(new byte[] { 1 }));
 		}
@@ -96,7 +96,7 @@ class JarURLConnectionTests {
 
 	@Test
 	void connectionToEntryUsingAbsoluteUrlForNestedEntry() throws Exception {
-		URL url = new URL("jar:file:" + getAbsolutePath() + "!/nested.jar!/3.dat");
+		URL url = new URL("jar:" + this.rootJarFile.toURI().toURL() + "!/nested.jar!/3.dat");
 		JarURLConnection connection = JarURLConnection.get(url, this.jarFile);
 		try (InputStream input = connection.getInputStream()) {
 			assertThat(input).hasSameContentAs(new ByteArrayInputStream(new byte[] { 3 }));
@@ -116,7 +116,7 @@ class JarURLConnectionTests {
 
 	@Test
 	void connectionToEntryUsingAbsoluteUrlForEntryFromNestedJarFile() throws Exception {
-		URL url = new URL("jar:file:" + getAbsolutePath() + "!/nested.jar!/3.dat");
+		URL url = new URL("jar:" + this.rootJarFile.toURI().toURL() + "!/nested.jar!/3.dat");
 		try (JarFile nested = this.jarFile.getNestedJarFile(this.jarFile.getEntry("nested.jar"))) {
 			try (InputStream input = JarURLConnection.get(url, nested).getInputStream()) {
 				assertThat(input).hasSameContentAs(new ByteArrayInputStream(new byte[] { 3 }));
@@ -136,7 +136,7 @@ class JarURLConnectionTests {
 
 	@Test
 	void connectionToEntryInNestedJarFromUrlThatUsesExistingUrlAsContext() throws Exception {
-		URL url = new URL(new URL("jar", null, -1, "file:" + getAbsolutePath() + "!/nested.jar!/", new Handler()),
+		URL url = new URL(new URL("jar", null, -1, this.rootJarFile.toURI().toURL() + "!/nested.jar!/", new Handler()),
 				"/3.dat");
 		try (JarFile nested = this.jarFile.getNestedJarFile(this.jarFile.getEntry("nested.jar"))) {
 			try (InputStream input = JarURLConnection.get(url, nested).getInputStream()) {
@@ -167,7 +167,7 @@ class JarURLConnectionTests {
 
 	@Test
 	void connectionToEntryUsingWrongAbsoluteUrlForEntryFromNestedJarFile() throws Exception {
-		URL url = new URL("jar:file:" + getAbsolutePath() + "!/w.jar!/3.dat");
+		URL url = new URL("jar:" + this.rootJarFile.toURI().toURL() + "!/w.jar!/3.dat");
 		try (JarFile nested = this.jarFile.getNestedJarFile(this.jarFile.getEntry("nested.jar"))) {
 			assertThatExceptionOfType(FileNotFoundException.class)
 					.isThrownBy(JarURLConnection.get(url, nested)::getInputStream);
@@ -176,7 +176,7 @@ class JarURLConnectionTests {
 
 	@Test
 	void getContentLengthReturnsLengthOfUnderlyingEntry() throws Exception {
-		URL url = new URL("jar:file:" + getAbsolutePath() + "!/nested.jar!/3.dat");
+		URL url = new URL("jar:" + this.rootJarFile.toURI().toURL() + "!/nested.jar!/3.dat");
 		try (JarFile nested = this.jarFile.getNestedJarFile(this.jarFile.getEntry("nested.jar"))) {
 			JarURLConnection connection = JarURLConnection.get(url, nested);
 			assertThat(connection.getContentLength()).isEqualTo(1);
@@ -185,7 +185,7 @@ class JarURLConnectionTests {
 
 	@Test
 	void getContentLengthLongReturnsLengthOfUnderlyingEntry() throws Exception {
-		URL url = new URL("jar:file:" + getAbsolutePath() + "!/nested.jar!/3.dat");
+		URL url = new URL("jar:" + this.rootJarFile.toURI().toURL() + "!/nested.jar!/3.dat");
 		try (JarFile nested = this.jarFile.getNestedJarFile(this.jarFile.getEntry("nested.jar"))) {
 			JarURLConnection connection = JarURLConnection.get(url, nested);
 			assertThat(connection.getContentLengthLong()).isEqualTo(1);
@@ -194,7 +194,7 @@ class JarURLConnectionTests {
 
 	@Test
 	void getLastModifiedReturnsLastModifiedTimeOfJarEntry() throws Exception {
-		URL url = new URL("jar:file:" + getAbsolutePath() + "!/1.dat");
+		URL url = new URL("jar:" + this.rootJarFile.toURI().toURL() + "!/1.dat");
 		JarURLConnection connection = JarURLConnection.get(url, this.jarFile);
 		assertThat(connection.getLastModified()).isEqualTo(connection.getJarEntry().getTime());
 	}
@@ -220,10 +220,6 @@ class JarURLConnectionTests {
 				.isEqualTo("\u00e1/b/\u00c7.class");
 	}
 
-	private String getAbsolutePath() {
-		return this.rootJarFile.getAbsolutePath().replace('\\', '/');
-	}
-
 	private String getRelativePath() {
 		return this.rootJarFile.getPath().replace('\\', '/');
 	}