What Is a Glob?-->轉java Doc

What Is a Glob?

Two methods in the Files 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.

getPathMatcher

PathMatcher pathMatcher = FileSystems.getDefault().getPathMatcher("glob:*[0-9]*");

pathMatcher.matches(path)

如果沒有glob沒加會拋出Exception in thread "main" java.lang.IllegalArgumentException


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

When the syntax is "glob" then the String representation of the path is matched using a limited pattern language that resembles regular expressions but with a simpler syntax. For example:

*.java	Matches a path that represents a file name ending in .java
*.*	Matches file names containing a dot
*.{java,class}	Matches file names ending with .java or .class
foo.?	Matches file names starting with foo. and a single character extension
/home/*/*	Matches /home/gus/data on UNIX platforms
/home/**	Matches /home/gus and /home/gus/data on UNIX platforms
C:\\*	Matches C:\foo and C:\bar on the Windows platform (note that the backslash is escaped; as a string literal in the Java Language the pattern would be "C:\\\\*")

The following rules are used to interpret glob patterns:

• The * character matches zero or more characters of a name component without crossing directory boundaries.
• The ** characters matches zero or more characters crossing directory boundaries.
• The ? character matches exactly one character of a name component.
• The backslash character (\) is used to escape characters that would otherwise be interpreted as special characters. The expression \\matches a single backslash and "\{" matches a left brace for example.
• The [ ] characters are a bracket expression that match a single character of a name component out of a set of characters. For example, [abc] matches "a", "b", or "c". The hyphen (-) may be used to specify a range so [a-z] specifies a range that matches from "a" to "z" (inclusive). These forms can be mixed so [abce-g] matches "a", "b", "c", "e", "f" or "g". If the character after the[ is a ! then it is used for negation so [!a-c] matches any character except "a", "b", or "c".
  Within a bracket expression the *, ? and \ characters match themselves. The (-) character matches itself if it is the first character within the brackets, or the first character after the ! if negating.
• The { } characters are a group of subpatterns, where the group matches if any subpattern in the group matches. The "," character is used to separate the subpatterns. Groups cannot be nested.

Globe跟正規劃表示法不太一樣ㄋㄟ!!!~~~