How to get layer styles?

[Lingchen218]

No description provided.

[MolecularMatters]

Can you explain what you mean by layer styles?
The PSD file format specification from Adobe knows about several different styles, all belonging to different sub-objects: https://www.adobe.com/devnet-apps/photoshop/fileformatashtml/

[Lingchen218]

That is, it will contain some drop shadow, outer glow, inner glow, pattern overlay, stroke, bevel and emboss. The effect of these options

[MolecularMatters]

Those are all contained in different objects, so you would have to read all of these objects as per the file format spec.

[Lingchen218]

Those are all contained in different objects, so you would have to read all of these objects as per the file format spec.

Which specific classes are used?

[MolecularMatters]

There are no classes for this in the library, currently.
If you mean which objects are used: you have to figure that out by looking at the file format spec posted above.