Java源码——文件/文件夹的路径分析（相对/绝对）（File and Directory Info Inquiry）

JHTP （Java how to program）中只给出了绝对路径的测试示例，自己查阅了网上资料，学会了相对路径的测试方法（在Eclipse）。

代码如下：

// Fig. 15.2: FileAndDirectoryInfo.java// File class used to obtain file and directory information.package ch15;import java.io.IOException;import java.nio.file.DirectoryStream;import java.nio.file.Files;import java.nio.file.Path;import java.nio.file.Paths;import java.util.Scanner;public class FileAndDirectoryInfo{   public static void main(String[] args) throws IOException   {      Scanner input = new Scanner(System.in);      System.out.println("Enter file or directory name:");      // create Path object based on user input      Path path = Paths.get(input.nextLine());      if (Files.exists(path)) // if path exists, output info about it      {         // display file (or directory) information      System.out.printf("%n%s exists%n", path.getFileName());      System.out.printf("%s a directory%n",       Files.isDirectory(path) ? "Is" : "Is not");      System.out.printf("%s an absolute path%n",       path.isAbsolute() ? "Is" : "Is not");      System.out.printf("Last modified: %s%n",       Files.getLastModifiedTime(path));      System.out.printf("Size: %s%n", Files.size(path));      System.out.printf("Path: %s%n", path);      System.out.printf("Absolute path: %s%n", path.toAbsolutePath());         if (Files.isDirectory(path)) // output directory listing         {            System.out.printf("%nDirectory contents:%n");                        // object for iterating through a directory's contents            DirectoryStream<Path> directoryStream =                Files.newDirectoryStream(path);               for (Path p : directoryStream)               System.out.println(p);         }       }       else // not file or directory, output error message      {         System.out.printf("%s does not exist%n", path);      }      }} // end class FileAndDirectoryInfo

测试结果：

1. Eclipse环境：

1）. 绝对路径

Enter file or directory name:
C:\01.iworkspace\eclipseWorkspace\jhtp_2017\src\ch15

ch15 exists
Is a directory
Is an absolute path
Last modified: 2017-04-29T16:01:31.563936Z
Size: 0
Path: C:\01.iworkspace\eclipseWorkspace\jhtp_2017\src\ch15
Absolute path: C:\01.iworkspace\eclipseWorkspace\jhtp_2017\src\ch15

Directory contents:
C:\01.iworkspace\eclipseWorkspace\jhtp_2017\src\ch15\FileAndDirectoryInfo.java
C:\01.iworkspace\eclipseWorkspace\jhtp_2017\src\ch15\test

2）. 相对路径

nter file or directory name:
src\ch15\test

test exists
Is a directory
Is not an absolute path
Last modified: 2017-04-29T16:04:17.5139Z
Size: 4096
Path: src\ch15\test
Absolute path: C:\01.iworkspace\eclipseWorkspace\jhtp_2017\src\ch15\test

Directory contents:
src\ch15\test\helloJava.java
src\ch15\test\relative path test.xlsx
src\ch15\test\相对路径测试文件.rtf

3）绝对路径（文件名）

Enter file or directory name:
C:\01.iworkspace\eclipseWorkspace\jhtp_2017\src\ch15\test\helloJava.java

helloJava.java exists
Is not a directory
Is an absolute path
Last modified: 2017-04-29T16:04:09.99025Z
Size: 0
Path: C:\01.iworkspace\eclipseWorkspace\jhtp_2017\src\ch15\test\helloJava.java
Absolute path: C:\01.iworkspace\eclipseWorkspace\jhtp_2017\src\ch15\test\helloJava.java

4）相对路径（文件名）

Enter file or directory name:
src\ch15\test\helloJava.java

helloJava.java exists
Is not a directory
Is not an absolute path
Last modified: 2017-04-29T16:04:09.99025Z
Size: 0
Path: src\ch15\test\helloJava.java
Absolute path: C:\01.iworkspace\eclipseWorkspace\jhtp_2017\src\ch15\test\helloJava.java

2. 命令行窗口

没搞定，下次再说吧。