What Is a Glob?

http://www-inf.int-evry.fr/cours/java/javatutorial/essential/io/fileOps.html#glob

Two methods in the Path class accept a glob argument, but what is a glob?
You can use glob syntax to specify pattern-matching behavior.
A glob pattern is specified as a string and is matched against other strings, such as directory or file names. Glob syntax follows several simple rules:

• An asterisk, *, matches any number of characters (including none).
• Two asterisks, **, works like * but crosses directory boundaries. This syntax is generally used for matching complete paths.
• A question mark, ?, matches exactly one character.
• Braces specify a collection of subpatterns. For example:
  • {sun,moon,stars} matches "sun", "moon", or "stars."
  • {temp*,tmp*} matches all strings beginning with "temp" or "tmp."
• Square brackets convey a set of single characters or, when the hyphen character (-) is used, a range of characters. For example:
  • [aeiou] matches any lowercase vowel.
  • [0-9] matches any digit.
  • [A-Z] matches any uppercase letter.
  • [a-z,A-Z] matches any uppercase or lowercase letter.
  Within the square brackets, *, ?, and \ match themselves.
• All other characters match themselves.
• To match *, ?, or the other special characters, you can escape them by using the backslash character, \. For example: \\ matches a single backslash, and \? matches the question mark.

Here are some examples of glob syntax:

• *.html – Matches all strings that end in .html
• ??? – Matches all strings with exactly three letters or digits
• *[0-9]* – Matches all strings containing a numeric value
• *.{htm,html,pdf} – Matches any string ending with .htm, .html or .pdf
• a?*.java – Matches any string beginning with a, followed by at least one letter or digit, and ending with .java
• {foo*,*[0-9]*} – Matches any string beginning with foo or any string containing a numeric value

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Note: If you are typing the glob pattern at the keyboard and it contains one of the special characters, you must put the pattern in quotes ("*"), use the backslash (\*), or use whatever escape mechanism is supported at the command line.

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The glob syntax is powerful and easy to use. However, if it is not sufficient for your needs, you can also use a regular expression. For more information, see the Regular Expressions lesson.
For more information about the glob sytnax, see the API specification for the getPathMatcher method in the FileSystem class.