Ranked in these QuestionsQuestion Ranking
Pro Several look and feels available
Pro Part of Java
Swing is part of the Java API.
Pro Very good and powerful API
E.g. separate models.
Pro Powerful controls
E.g. JTable which works fine on every platform with very large row counts, e.g. 100.000+.
Con Bugfixes rely on Oracle
Con No real native look
Though the importance of the native look seems to have dropped the last years by the raise of in-browser-applications.