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diff --git a/jimfs/src/main/java/com/google/common/jimfs/Handler.java b/jimfs/src/main/java/com/google/common/jimfs/Handler.java
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+/*
+ * Copyright 2015 Google Inc.
+ *
+ * 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 com.google.common.jimfs;
+
+import static com.google.common.base.Preconditions.checkArgument;
+
+import java.io.IOException;
+import java.net.InetAddress;
+import java.net.URL;
+import java.net.URLConnection;
+import java.net.URLStreamHandler;
+
+/**
+ * {@link URLStreamHandler} implementation for jimfs. Named {@code Handler} so that the class can be
+ * found by Java as described in the documentation for {@link URL#URL(String, String, int, String)
+ * URL}.
+ *
+ * <p>This class is only public because it is necessary for Java to find it. It is not intended to
+ * be used directly.
+ *
+ * @author Colin Decker
+ * @since 1.1
+ */
+public final class Handler extends URLStreamHandler {
+
+  private static final String JAVA_PROTOCOL_HANDLER_PACKAGES = "java.protocol.handler.pkgs";
+
+  /**
+   * Registers this handler by adding the package {@code com.google.common} to the system property
+   * {@code "java.protocol.handler.pkgs"}. Java will then look for this class in the {@code jimfs}
+   * (the name of the protocol) package of {@code com.google.common}.
+   *
+   * @throws SecurityException if the system property that needs to be set to register this handler
+   *     can't be read or written.
+   */
+  static void register() {
+    register(Handler.class);
+  }
+
+  /** Generic method that would allow registration of any properly placed {@code Handler} class. */
+  static void register(Class<? extends URLStreamHandler> handlerClass) {
+    checkArgument("Handler".equals(handlerClass.getSimpleName()));
+
+    String pkg = handlerClass.getPackage().getName();
+    int lastDot = pkg.lastIndexOf('.');
+    checkArgument(lastDot > 0, "package for Handler (%s) must have a parent package", pkg);
+
+    String parentPackage = pkg.substring(0, lastDot);
+
+    String packages = System.getProperty(JAVA_PROTOCOL_HANDLER_PACKAGES);
+    if (packages == null) {
+      packages = parentPackage;
+    } else {
+      packages += "|" + parentPackage;
+    }
+    System.setProperty(JAVA_PROTOCOL_HANDLER_PACKAGES, packages);
+  }
+
+  /** @deprecated Not intended to be called directly; this class is only for use by Java itself. */
+  @Deprecated
+  public Handler() {} // a public, no-arg constructor is required
+
+  @Override
+  protected URLConnection openConnection(URL url) throws IOException {
+    return new PathURLConnection(url);
+  }
+
+  @Override
+  @SuppressWarnings("UnsynchronizedOverridesSynchronized") // no need to synchronize to return null
+  protected InetAddress getHostAddress(URL url) {
+    // jimfs uses the URI host to specify the name of the file system being used.
+    // In the default implementation of getHostAddress(URL), a non-null host would cause an attempt
+    // to look up the IP address, causing a slowdown on calling equals/hashCode methods on the URL
+    // object. By returning null, we speed up equality checks on URL's (since there isn't an IP to
+    // connect to).
+    return null;
+  }
+}