ditaa: depend on openjdk

Formula/ditaa.rb

@@ -3,14 +3,18 @@ class Ditaa < Formula
   homepage "https://ditaa.sourceforge.io/"
   url "https://github.com/stathissideris/ditaa/releases/download/v0.11.0/ditaa-0.11.0-standalone.jar"
   sha256 "9418aa63ff6d89c5d2318396f59836e120e75bea7a5930c4d34aa10fe7a196a9"
+  revision 1
 
   bottle :unneeded
 
-  depends_on :java
+  depends_on "openjdk"
 
   def install
     libexec.install "ditaa-#{version}-standalone.jar"
-    bin.write_jar_script libexec/"ditaa-#{version}-standalone.jar", "ditaa"
+    (bin/"ditaa").write <<~EOS
+      #!/bin/bash
+      exec "#{Formula["openjdk"].opt_bin}/java" -jar "#{libexec}/ditaa-#{version}-standalone.jar" "$@"
+    EOS
   end
 
   test do