Jul 29, 2021 Let’s look at an example using the Files class and the readAllLines method. The readAllLines method accepts a Path. Path class can be considered an upgrade of the java.io.File with some additional operations in place. Reading a Small File. The toPath method may be used to obtain a Path from the abstract path name represented by a java.io.File object. The resulting Path can be used to operate on the same file as the java.io.File object. In addition, the toFile method is useful to construct a File from the String representation of a Path. Java.nio.file.Paths public final class Paths extends Object This class consists exclusively of static methods that return a Path by converting a path string or URI. In the following code shows how to use Paths.get(String first, String.
- File Path In For Java Programming
- File Path In For Java 10
- File Path In Javascript
- File Path In For Java
- File Path In For Java 8
1. Overview
May 12, 2020 Java.io.File Class in Java. The File class is Java’s representation of a file or directory path name. Because file and directory names have different formats on different platforms, a simple string is not adequate to name them. The File class contains several methods for working with the path name, deleting and renaming files, creating new.
The java.io.File class has three methods — getPath(), getAbsolutePath() and getCanonicalPath() — to obtain the filesystem path.
In this article, we'll have a quick look at the differences between them and discuss a use case where you may choose to use one over the others.
2. Method Definitions and Examples
Let's start by going over the definitions of the three methods, along with examples based on having the following directory structure present in the user's home directory:
2.1. getPath()
Simply put, getPath() returns the String representation of the file's abstract pathname. This is essentially the pathname passed to the File constructor.
So, if the File object was created using a relative path, the returned value from getPath() method would also be a relative path.
If we invoke the following code from the {user.home}/baeldung directory:
The path variable would have the value:
Notice that for the Windows system, the name-separator character has changed from the forward slash(/) character, which was passed to the constructor, to the backslash () character. This is because the returned String always uses the platform's default name-separator character.
2.2. getAbsolutePath()
The getAbsolutePath() method returns the pathname of the file after resolving the path for the current user directory — this is called an absolute pathname. So, for our previous example, file.getAbsolutePath() would return:
This method only resolves the current directory for a relative path. Shorthand representations (such as “.” and “..”) are not resolved further. Hence when we execute the following code from the directory {user.home}/baeldung:
The value of the variable path would be:
2.3. getCanonicalPath()
The getCanonicalPath() method goes a step further and resolves the absolute pathname as well as the shorthands or redundant names like “.” and “..“ as per the directory structure. It also resolves symbolic links on Unix systems and converts the drive letter to a standard case on Windows systems.
So for the previous example, getCanonicalPath() method would return:
Let's take another example. Given current directory as ${user.home}/baeldung and File object created using the parameter new File(“bar/baz/./baz-one.txt”), the output for getCanonicalPath() would be:
It's worth mentioning that a single file on the filesystem can have an infinite number of absolute paths since there's an infinite number of ways shorthand representations can be used. However, the canonical path will always be unique since all such representations are resolved.
Unlike the last two methods, getCanonicalPath() may throw IOException because it requires filesystem queries.
For example, on Windows systems, if we create a File object with one of the illegal characters, resolving the canonical path will throw an IOException:
3. Use Case
File Path In For Java Programming
Let's say we're writing a method that takes in a File object as a parameter and saves its fully qualified name into a database. We don't know whether the path is relative or contains shorthands. In this case, we may want to use getCanonicalPath().
However, since getCanonicalPath() reads the filesystem, it comes at a performance cost. If we are sure that there are no redundant names or symbolic links and drive letter case is standardized (if using a Windows OS), then we should prefer using getAbsoultePath().
4. Conclusion
File Path In For Java 10
In this quick tutorial, we covered the differences between the three File methods to get filesystem path. We have also shown a use case where one method may be preferred over the other.
A Junit test class demonstrating the examples of this article can be found over on GitHub.
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>> CHECK OUT THE COURSE- How to set the path of JDK in Windows OS
The path is required to be set for using tools such as javac, java, etc.
If you are saving the Java source file inside the JDK/bin directory, the path is not required to be set because all the tools will be available in the current directory.
However, if you have your Java file outside the JDK/bin folder, it is necessary to set the path of JDK.
There are two ways to set the path in Java:
- Temporary
- Permanent
1) How to set the Temporary Path of JDK in Windows
To set the temporary path of JDK, you need to follow the following steps:
- Open the command prompt
- Copy the path of the JDK/bin directory
- Write in command prompt: set path=copied_path
For Example:
Let's see it in the figure given below:
2) How to set Permanent Path of JDK in Windows
File Path In Javascript
For setting the permanent path of JDK, you need to follow these steps:
- Go to MyComputer properties -> advanced tab -> environment variables -> new tab of user variable -> write path in variable name -> write path of bin folder in variable value -> ok -> ok -> ok
For Example:
File Path In For Java
1) Go to MyComputer properties |
2) Click on the advanced tab |
3) Click on environment variables |
4) Click on the new tab of user variables |
5) Write the path in the variable name |
6) Copy the path of bin folder |
7) Paste path of bin folder in the variable value |
8) Click on ok button |
9) Click on ok button |
Now your permanent path is set. You can now execute any program of java from any drive.
Setting Java Path in Linux OS
Setting path in Linux OS is the same as setting the path in the Windows OS. But, here we use the export tool rather than set. Let's see how to set path in Linux OS:
Here, we have installed the JDK in the home directory under Root (/home).
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