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diff --git a/java/com/google/gwtexpui/safehtml/client/LinkFindReplace.java b/java/com/google/gwtexpui/safehtml/client/LinkFindReplace.java
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+++ b/java/com/google/gwtexpui/safehtml/client/LinkFindReplace.java
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+// Copyright (C) 2013 The Android Open Source Project
+//
+// 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.gwtexpui.safehtml.client;
+
+import com.google.gwt.regexp.shared.RegExp;
+
+/**
+ * A Find/Replace pair whose replacement string is a link.
+ *
+ * <p>It is safe to pass arbitrary user-provided links to this class. Links are sanitized as
+ * follows:
+ *
+ * <ul>
+ *   <li>Only http(s) and mailto links are supported; any other scheme results in an {@link
+ *       IllegalArgumentException} from {@link #replace(String)}.
+ *   <li>Special characters in the link after regex replacement are escaped with {@link
+ *       SafeHtmlBuilder}.
+ * </ul>
+ */
+public class LinkFindReplace implements FindReplace {
+  public static boolean hasValidScheme(String link) {
+    int colon = link.indexOf(':');
+    if (colon < 0) {
+      return true;
+    }
+    String scheme = link.substring(0, colon);
+    return "http".equalsIgnoreCase(scheme)
+        || "https".equalsIgnoreCase(scheme)
+        || "mailto".equalsIgnoreCase(scheme);
+  }
+
+  private RegExp pat;
+  private String link;
+
+  protected LinkFindReplace() {}
+
+  /**
+   * @param find regular expression pattern to match substrings with.
+   * @param link replacement link href. Capture groups within {@code find} can be referenced with
+   *     {@code $<i>n</i>}.
+   */
+  public LinkFindReplace(String find, String link) {
+    this.pat = RegExp.compile(find);
+    this.link = link;
+  }
+
+  @Override
+  public RegExp pattern() {
+    return pat;
+  }
+
+  @Override
+  public String replace(String input) {
+    String href = pat.replace(input, link);
+    if (!hasValidScheme(href)) {
+      throw new IllegalArgumentException("Invalid scheme (" + toString() + "): " + href);
+    }
+    return new SafeHtmlBuilder()
+        .openAnchor()
+        .setAttribute("href", href)
+        .append(SafeHtml.asis(input))
+        .closeAnchor()
+        .asString();
+  }
+
+  @Override
+  public String toString() {
+    return "find = " + pat.getSource() + ", link = " + link;
+  }
+}