使用getPathMatcher的Glob模式

Question

从Oathy考试的"Kathy Sierra Bert Bates"一书中我发现了以下代码

public class FileTest {

    public static void matches(Path path, String glob){
        PathMatcher matcher = FileSystems.getDefault().getPathMatcher(glob);
        System.out.println(matcher.matches(path));
    }
    public static void main(String[] args) throws IOException {
        Path path = Paths.get("/com/java/One.java");
        matches(path, "glob:*.java");
        matches(path, "glob:**/*.java");
        matches(path, "glob:*");
        matches(path, "glob:**");

    }
}

输出:

false
true
false
true

我无法清楚地理解输出.有人会解释我吗？让我知道我的例子是什么是跨越目录边界.谢谢洛基

Answer 1

public class FileTest {

    public static void matches(Path path, String glob){
        PathMatcher matcher = FileSystems.getDefault().getPathMatcher(glob);
        System.out.println(matcher.matches(path));
    }
    public static void main(String[] args) throws IOException {
        Path path = Paths.get("/com/java/One.java");
        matches(path, "glob:*.java");       // regular expression that matches any file path that end with .java so it will return the value as true
        matches(path, "glob:**/*.java"); // regular expression ** characters matches zero or more characters crossing directory boundaries so it will match complete path but if you put /* it will search for a path like this /com/java//one.java soe here it will not match the path and will return value as false.
        matches(path, "glob:*"); // this will match any path and return value as true.
        matches(path, "glob:**"); // this will complete path crossing directory so it will return you value as true.

    }
}

在上面的程序中，当您调用与路径匹配的 as"/com/java/One.java"和 glob 正则表达式来搜索或匹配路径时，该函数将获取值并执行操作并返回 true 或 false。输出：

true
false
true
true

如果您使用的是windows平台，那么您需要按如下方式修改您的程序。

public class match {

  public static void matches(Path path, String glob){
    PathMatcher matcher = FileSystems.getDefault().getPathMatcher(glob);
    System.out.println(matcher.matches(path));
  }
  public static void main(String[] args) throws IOException {
    Path path = Paths.get("\\com\\java\\One.java");
    matches(path, "glob:*.java");
    matches(path, "glob:**\\*.java");
    matches(path, "glob:*");
    matches(path, "glob:**");

  }
}

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