diff --git a/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/jar/JarURLConnection.java b/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/jar/JarURLConnection.java
index 0e26e6a2ef..28abc20f10 100644
--- a/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/jar/JarURLConnection.java
+++ b/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/jar/JarURLConnection.java
@@ -17,17 +17,18 @@
 package org.springframework.boot.loader.jar;
 
 import java.io.ByteArrayOutputStream;
+import java.io.File;
 import java.io.FileNotFoundException;
 import java.io.FilePermission;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.UnsupportedEncodingException;
 import java.net.MalformedURLException;
+import java.net.URI;
 import java.net.URL;
 import java.net.URLConnection;
 import java.net.URLEncoder;
 import java.net.URLStreamHandler;
-
 import java.security.Permission;
 
 /**
@@ -62,8 +63,6 @@ class JarURLConnection extends java.net.JarURLConnection {
 
 	private static final JarEntryName EMPTY_JAR_ENTRY_NAME = new JarEntryName("");
 
-	private static final String FILE_COLON_DOUBLE_SLASH = "file://";
-
 	private static final String READ_ACTION = "read";
 
 	private static ThreadLocal<Boolean> useFastExceptions = new ThreadLocal<Boolean>();
@@ -82,7 +81,7 @@ class JarURLConnection extends java.net.JarURLConnection {
 		// What we pass to super is ultimately ignored
 		super(EMPTY_JAR_URL);
 		this.url = url;
-		String spec = getNormalizedFile(url)
+		String spec = getNormalizedFileUrl(url)
 				.substring(jarFile.getUrl().getFile().length());
 		int separator;
 		while ((separator = spec.indexOf(SEPARATOR)) > 0) {
@@ -95,11 +94,10 @@ class JarURLConnection extends java.net.JarURLConnection {
 				READ_ACTION);
 	}
 
-	private String getNormalizedFile(URL url) {
-		if (!url.getFile().startsWith(FILE_COLON_DOUBLE_SLASH)) {
-			return url.getFile();
-		}
-		return "file:" + url.getFile().substring(FILE_COLON_DOUBLE_SLASH.length());
+	private String getNormalizedFileUrl(URL url) {
+		String fileName = url.getFile();
+		return new File(URI.create(fileName).getSchemeSpecificPart()).getAbsoluteFile()
+				.toURI().toString() + (fileName.endsWith("/") ? "/" : "");
 	}
 
 	private JarFile getNestedJarFile(JarFile jarFile, String name) throws IOException {
diff --git a/spring-boot-tools/spring-boot-loader/src/test/java/org/springframework/boot/loader/jar/JarURLConnectionTests.java b/spring-boot-tools/spring-boot-loader/src/test/java/org/springframework/boot/loader/jar/JarURLConnectionTests.java
new file mode 100644
index 0000000000..cd7e8c4a29
--- /dev/null
+++ b/spring-boot-tools/spring-boot-loader/src/test/java/org/springframework/boot/loader/jar/JarURLConnectionTests.java
@@ -0,0 +1,107 @@
+/*
+ * Copyright 2012-2016 the original author or authors.
+ *
+ * Licensed 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.springframework.boot.loader.jar;
+
+import java.io.ByteArrayInputStream;
+import java.io.File;
+import java.net.URL;
+
+import org.junit.Before;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.TemporaryFolder;
+
+import org.springframework.boot.loader.TestJarCreator;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Tests for {@link JarURLConnection}.
+ *
+ * @author Andy Wilkinson
+ */
+public class JarURLConnectionTests {
+
+	@Rule
+	public TemporaryFolder temporaryFolder = new TemporaryFolder(new File("target"));
+
+	private File rootJarFile;
+
+	private JarFile jarFile;
+
+	@Before
+	public void setup() throws Exception {
+		this.rootJarFile = this.temporaryFolder.newFile();
+		TestJarCreator.createTestJar(this.rootJarFile);
+		this.jarFile = new JarFile(this.rootJarFile);
+	}
+
+	@Test
+	public void connectionToRootUsingAbsoluteUrl() throws Exception {
+		URL absoluteUrl = new URL(
+				"jar:file:" + this.rootJarFile.getAbsoluteFile() + "!/");
+		assertThat(new JarURLConnection(absoluteUrl, this.jarFile).getContent())
+				.isSameAs(this.jarFile);
+	}
+
+	@Test
+	public void connectionToRootUsingRelativeUrl() throws Exception {
+		URL relativeUrl = new URL("jar:file:" + this.rootJarFile + "!/");
+		assertThat(new JarURLConnection(relativeUrl, this.jarFile).getContent())
+				.isSameAs(this.jarFile);
+	}
+
+	@Test
+	public void connectionToEntryUsingAbsoluteUrl() throws Exception {
+		URL absoluteUrl = new URL(
+				"jar:file:" + this.rootJarFile.getAbsoluteFile() + "!/1.dat");
+		assertThat(new JarURLConnection(absoluteUrl, this.jarFile).getInputStream())
+				.hasSameContentAs(new ByteArrayInputStream(new byte[] { 1 }));
+	}
+
+	@Test
+	public void connectionToEntryUsingRelativeUrl() throws Exception {
+		URL relativeUrl = new URL("jar:file:" + this.rootJarFile + "!/1.dat");
+		assertThat(new JarURLConnection(relativeUrl, this.jarFile).getInputStream())
+				.hasSameContentAs(new ByteArrayInputStream(new byte[] { 1 }));
+	}
+
+	@Test
+	public void connectionToEntryUsingAbsoluteUrlWithFileColonSlashSlashPrefix()
+			throws Exception {
+		URL absoluteUrl = new URL(
+				"jar:file:/" + this.rootJarFile.getAbsoluteFile() + "!/1.dat");
+		assertThat(new JarURLConnection(absoluteUrl, this.jarFile).getInputStream())
+				.hasSameContentAs(new ByteArrayInputStream(new byte[] { 1 }));
+	}
+
+	@Test
+	public void connectionToEntryUsingAbsoluteUrlForNestedEntry() throws Exception {
+		URL absoluteUrl = new URL(
+				"jar:file:" + this.rootJarFile.getAbsoluteFile() + "!/nested.jar!/3.dat");
+		assertThat(new JarURLConnection(absoluteUrl, this.jarFile).getInputStream())
+				.hasSameContentAs(new ByteArrayInputStream(new byte[] { 3 }));
+	}
+
+	@Test
+	public void connectionToEntryUsingRelativeUrlForNestedEntry() throws Exception {
+		URL relativeUrl = new URL("jar:file:" + this.rootJarFile + "!/nested.jar!/3.dat");
+		assertThat(new JarURLConnection(relativeUrl, this.jarFile).getInputStream())
+				.hasSameContentAs(new ByteArrayInputStream(new byte[] { 3 }));
+	}
+
+}