try-with-resources

A resource is anything a program opens and must close again: a log file, a database connection, a network socket, a lock held while a critical section runs. Forgetting to close one of these leaks memory, ties up database connections, or leaves locks held forever. Java's try-with-resources statement solves the problem at the language level. The resource is declared at the top of the try, and the compiler guarantees it gets closed when the block ends, no matter how the block ends. This lesson covers the problem manual cleanup creates, the try-with-resources syntax, the AutoCloseable interface, the close order for multiple resources, suppressed exceptions, the Java 9 short form, and how try-with-resources interacts with catch and finally.