How to get just the parent directory name of a specific file

问题

How to get ddd from the path name where the test.java resides.

File file = new File(\"C:/aaa/bbb/ccc/ddd/test.java\");

回答1:

Use File's getParentFile() method and String.lastIndexOf() to retrieve just the immediate parent directory.

Mark's comment is a better solution thanlastIndexOf():

file.getParentFile().getName();

These solutions only works if the file has a parent file (e.g., created via one of the file constructors taking a parent File). When getParentFile() is null you'll need to resort to using lastIndexOf, or use something like Apache Commons' FileNameUtils.getFullPath():

FilenameUtils.getFullPathNoEndSeparator(file.getAbsolutePath());
=> C:/aaa/bbb/ccc/ddd

There are several variants to retain/drop the prefix and trailing separator. You can either use the same FilenameUtils class to grab the name from the result, use lastIndexOf, etc.

回答2:

File f = new File("C:/aaa/bbb/ccc/ddd/test.java");
System.out.println(f.getParentFile().getName())

f.getParentFile() can be null, so you should check it.

回答3:

Use below,

File file = new File("file/path");
String parentPath = file.getAbsoluteFile().getParent();

回答4:

In Java 7 you have the new Paths api. The modern and cleanest solution is:

Paths.get("C:/aaa/bbb/ccc/ddd/test.java").getParent().getFileName();

Result would be:

C:/aaa/bbb/ccc/ddd

回答5:

If you have just String path and don't want to create new File object you can use something like:

public static String getParentDirPath(String fileOrDirPath) {
    boolean endsWithSlash = fileOrDirPath.endsWith(File.separator);
    return fileOrDirPath.substring(0, fileOrDirPath.lastIndexOf(File.separatorChar, 
            endsWithSlash ? fileOrDirPath.length() - 2 : fileOrDirPath.length() - 1));
}

回答6:

File file = new File("C:/aaa/bbb/ccc/ddd/test.java");
File curentPath = new File(file.getParent());
//get current path "C:/aaa/bbb/ccc/ddd/"
String currentFolder= currentPath.getName().toString();
//get name of file to string "ddd"

if you need to append folder "ddd" by another path use;

String currentFolder= "/" + currentPath.getName().toString();

回答7:

From java 7 I would prefer to use Path. You only need to put path into:

Path dddDirectoryPath = Paths.get("C:/aaa/bbb/ccc/ddd/test.java");

and create some get method:

public String getLastDirectoryName(Path directoryPath) {
   int nameCount = directoryPath.getNameCount();
   return directoryPath.getName(nameCount - 1);
}

回答8:

In Groovy:

There is no need to create a File instance to parse the string in groovy. It can be done as follows:

String path = "C:/aaa/bbb/ccc/ddd/test.java"
path.split('/')[-2]  // this will return ddd

The split will create the array [C:, aaa, bbb, ccc, ddd, test.java] and index -2 will point to entry before the last one, which in this case is ddd

回答9:

    //get the parentfolder name
    File file = new File( System.getProperty("user.dir") + "/.");
    String parentPath = file.getParentFile().getName();

来源：https://stackoverflow.com/questions/8197049/how-to-get-just-the-parent-directory-name-of-a-specific-file

标签

java

groovy

java-io