From Effective Java 2/e by Joshua Bloch
Advantages
- By using a standard library, you take advantage of the knowledge of the experts who wrote it and the experience of those who used it before you
- You don’t have to waste your time writing ad hoc solutions to problems that are only marginally related to your work
- Their performance tends to improve over time, with no effort on your part
- Libraries also tend to gain new functionality over time
- You place your code in the mainstream