Non netsted classes or interfacnes may be public or package private

Classes without a modifier are package private (only accesible within the same package)

Members of a class (attriubes/fields/instance variables, methods, constructors, nested types) can be any of the four access levels

Access is based on static not dynamic types -> class not object

Only override a method with one that is at least as permissive

protected {…}

public declarations are for ‘clients’,

package private is for use in implementation in a class that must be known to other classes that assist in the implemetation (use it but don’t reveal it)

protected declarations are part of implementation that subtypes may need but clients don’t generally use -> can use constructor in a subtype but cannot invoke constuctor outside

private (need to know basis), only that class needs