1 files changed, 93 insertions, 0 deletions
diff --git a/gerrit-gwtexpui/src/main/java/com/google/gwtexpui/linker/server/UserAgentRule.java b/gerrit-gwtexpui/src/main/java/com/google/gwtexpui/linker/server/UserAgentRule.java
new file mode 100644
index 0000000000..366b6c57a3
--- /dev/null
+++ b/gerrit-gwtexpui/src/main/java/com/google/gwtexpui/linker/server/UserAgentRule.java
@@ -0,0 +1,93 @@
+// Copyright (C) 2009 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.linker.server;
+
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+import static java.util.regex.Pattern.compile;
+
+import javax.servlet.http.HttpServletRequest;
+
+/**
+ * Selects the value for the {@code user.agent} property.
+ * <p>
+ * Examines the {@code User-Agent} HTTP request header, and tries to match it to
+ * known {@code user.agent} values.
+ * <p>
+ * Ported from JavaScript in {@code com.google.gwt.user.UserAgent.gwt.xml}.
+ */
+public class UserAgentRule implements Rule {
+  private static final Pattern msie = compile(".*msie ([0-9]+)\\.([0-9]+).*");
+  private static final Pattern gecko = compile(".*rv:([0-9]+)\\.([0-9]+).*");
+
+  public String getName() {
+    return "user.agent";
+  }
+
+  @Override
+  public String select(HttpServletRequest req) {
+    String ua = req.getHeader("User-Agent");
+    if (ua == null) {
+      return null;
+    }
+
+    ua = ua.toLowerCase();
+
+    if (ua.indexOf("opera") != -1) {
+      return "opera";
+
+    } else if (ua.indexOf("webkit") != -1) {
+      return "safari";
+
+    } else if (ua.indexOf("msie") != -1) {
+      // GWT 2.0 uses document.documentMode here, which we can't do
+      // on the server side.
+
+      Matcher m = msie.matcher(ua);
+      if (m.matches() && m.groupCount() == 2) {
+        int v = makeVersion(m);
+        if (v >= 10000) {
+          return "ie10";
+        }
+        if (v >= 9000) {
+          return "ie9";
+        }
+        if (v >= 8000) {
+          return "ie8";
+        }
+        if (v >= 6000) {
+          return "ie6";
+        }
+      }
+      return null;
+
+    } else if (ua.indexOf("gecko") != -1) {
+      Matcher m = gecko.matcher(ua);
+      if (m.matches() && m.groupCount() == 2) {
+        if (makeVersion(m) >= 1008) {
+          return "gecko1_8";
+        }
+      }
+      return "gecko";
+    }
+
+    return null;
+  }
+
+  private int makeVersion(Matcher result) {
+    return (Integer.parseInt(result.group(1)) * 1000)
+        + Integer.parseInt(result.group(2));
+  }
+}