Build with Java 8

Change-Id: I06f811fc46a606b719582c0724e8d0c89e823b37
diff --git a/gerrit-main/src/main/java/Main.java b/gerrit-main/src/main/java/Main.java
index a29f1c6..58de6a4 100644
--- a/gerrit-main/src/main/java/Main.java
+++ b/gerrit-main/src/main/java/Main.java
@@ -31,11 +31,11 @@
 
   private static boolean onSupportedJavaVersion() {
     final String version = System.getProperty("java.specification.version");
-    if (1.7 <= parse(version)) {
+    if (1.8 <= parse(version)) {
       return true;
 
     }
-    System.err.println("fatal: Gerrit Code Review requires Java 7 or later");
+    System.err.println("fatal: Gerrit Code Review requires Java 8 or later");
     System.err.println("       (trying to run on Java " + version + ")");
     return false;
   }