PackageListener (BlueJ Extensions API)

```
public interface PackageListener
```
This interface allows an extension to listen for events on BlueJ packages.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`void`	`packageClosing(PackageEvent event)`	This method will be called when a package is about to be closed.
`void`	`packageOpened(PackageEvent event)`	This method will be called when a package has been opened.

- Method Detail
  - packageOpened
```
void packageOpened(PackageEvent event)
```
    This method will be called when a package has been opened. If a long operation must be performed the extension should start a Thread.
  - packageClosing
```
void packageClosing(PackageEvent event)
```
    This method will be called when a package is about to be closed. If a long operation must be performed the extension should start a Thread.