Some tables in java.desktop module use border="1" attribute on <table> element to enable borders around table cells. The most prominent example is src/java.desktop/share/classes/javax/swing/plaf/synth/doc-files/componentProperties.html file.

W3C HTML Validator issues an error for this attribute although HTML 5 allows it.

To achieve the same visual presentation, the following CSS rules can be used:
table {border: outset 1px}
th, td {border: inset 1px}