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Types should always be imported by their canonical name. The canonical name of a
top-level class is the fully-qualified name of the package, followed by a '.',
followed by the name of the class. The canonical name of a member class is the
canonical name of its declaring class, followed by a '.', followed by the name
of the member class.
Fully-qualified member class names are not guaranteed to be canonical. Consider
some member class M declared in a class C. There may be another class D that
extends C and inherits M. Therefore M can be accessed using the fully-qualified
name of D, followed by a '.', followed by 'M'. Since M is not declared in D,
this name is not canonical.
The JLS ยง7.5.3 requires all single static imports to *start* with a canonical
type name, but the fully-qualified name of the imported member is not required
to be canonical.
Importing types using non-canonical names is unnecessary and unclear, and should
be avoided.
Example:
```java
package a;
class One {
static class Inner {}
}
```
```java
package a;
class Two extends One {}
```
An import of `Inner` should always refer to it using the canonical name
`a.One.Inner`, not `a.Two.Inner`.
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