vs.java

// VMM is VisualMappingManager
VisualStyle psiStyle = null;
for (VisualStyle style : vmm.getAllVisualStyles()) {
    if (style.getTitle().equals(PSIMI25VisualStyleBuilder.DEF_VS_NAME)) {
        psiStyle = style;
        break;
    }
}
if (psiStyle == null) {
    psiStyle = vsBuilder.getVisualStyle();
    vmm.addVisualStyle(psiStyle);
}

vmm.setCurrentVisualStyle(psiStyle);