In my Applet I try to paint text with greek characters but
characters appear as boxes.
This can always happen if you rely on the fonts installed on the client
site. If there is a god chance that your users do have an appropriate
font, you can try to use that in your applet. If it is not likely that
your users have the specific font, you should consider licensing and
bundling an appropriate font with your applet. Java contains a TrueType
font renderere, and since Java 1.4 loading the font data from a
resource (a URL pointing to your jar on your server) even works.
What I can do to write non-english
characters? (Chinese, Greek, Arabian, ...) I retrieve text from
*.properties files. Can *.properties files be in unicode format?
Yes and no. Properties files have to be encoded in ISO Latin 1 (read
the API documentation of java.utilProperties). But you can specify all
Unicode characters using an escape mechanism \u<xharacter code>. The
SDK also contains a converter to convert a text file in a non Latin 1
encoding to the encoding required by properties files, includig the
generation of these escape codes. Read the documentation of your SDK.