GUI: How can I find out if certain Unicode characters are supported?

问题

I noticed that Metal L&F doesn't support certain arrow characters from Unicode, while Nimbus and GTK L&Fs do support them.

Unsupported characters are just displayed as: ...

Can I

1. either look up (manually), which L&F supports which Unicode chars,
2. or find it out at runtime?

EDIT: Or, should it only depend on the L&F's default font, my question perhaps should be:
"how do I find out, which Java font supports which Unicode characters?"

回答1:

You can use the canDisplay method to test if a java.awt.Font object can display a given character. You can typically get the font from GUI components using the getFont() method.

回答2:

If you know which unicode block contains the arrows you need, you can look it up here. Unfortunately there doesn't seem to be a page for newer JDK's.

回答3:

Using this piece of code you use almost every Unicode ta.setFont(new java.awt.Font("Segoe UI Emoji", 1, 20));

来源：https://stackoverflow.com/questions/4557597/gui-how-can-i-find-out-if-certain-unicode-characters-are-supported