The hierarchical relationship of packages in Java
The package in Java is logically not nested, that is to say:
Java.lang and JAVA.LANG.AWT are two parallel packages, equal in status and unrelated to each other. Just a name called Java.lang another name is JAVA.LANG.AWT.
So since the packages in Java are parallel, why "." is allowed in the name. The appearance of??? Don't you confuse yourself???
In fact, the package is logically not nested, but in the file organization is there! Plainly, a directory represents a package, then the Java directory represents a Java-named package, and this directory has a lang directory, so he represents the name of Java.lang's package, then Lang under the sub-directory AWT naturally corresponding to the name of JAva.lang.aw T's bag. This is clear, actually want to still have a certain scientific and technological content and rationality.
Finally, the package is used to create packages, and import imports them.
Java Daily-002