diff --git a/docs/xx_java_docs.md b/docs/xx_java_docs.md
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+https://binfalse.de/2015/10/05/javadoc-cheats-sheet/
+
+<iframe width="100%" height="800px" src="../media/javadoc_main.pdf">
+</iframe>
\ No newline at end of file
diff --git a/media/javadoc_main.pdf b/media/javadoc_main.pdf
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