Just catch the FileNotFoundException. The file system has to test whether the file exists anyway. There is no point in doing all that twice, and several reasons not to, such as:. Don't try to second-guess the system. It knows. And don't try to predict the future. In general the best way to test whether any resource is available is just to try to use it. For me a combination of the accepted answer by Sean A. Harney and the resulting comment by Cort3z seems to be the best solution. Therefore, no need to check if Files.
Note that other parameters are options indicating how links should be handled. By default, symbolic links are followed. From Java Oracle documentation.
There is specific purpose to design these methods. We can't say use anyone to check file exist or not. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. How do I check if a file exists in Java?
Ask Question. Asked 12 years, 1 month ago. Active 1 year, 7 months ago. Viewed 1. Improve this question. Arsen Khachaturyan 7, 4 4 gold badges 36 36 silver badges 38 38 bronze badges. Also want to add that you would want to check for appropriate file permissions: docs.
File has methods canRead , canWrite , and canExecute to check for that. It should be noted that this is dangerous. The filesystem can change at any time, including right after your "does this file exist" method returns. Since you have to handle that case anyway, such a method is of questionable utility. If you are going to open the file, the correct way to do so is to open the file and handle the relevant exception.
Either that, or it's a specially designed Java chip. If the former, you are in a concurrent environment. Other processes could change the filesystem out from under you. Add a comment. Active Oldest Votes. Improve this answer. DVK k 31 31 gold badges silver badges bronze badges. Sean A. Harney Sean A. Harney There are some cases where exists will return an incorrect result. For example, when using an NFS file system there is an issue with stale file handles: bugs. Use if f. Chris Dail Chris Dail By using nio in Java SE 7, import java.
Wonil Wonil 5, 2 2 gold badges 35 35 silver badges 54 54 bronze badges. What is the advatages compared to new File path. For a palin exists check — Raghu K Nair. RaghuKNair java. I just tried it myself and java. Win7 Java 1. This also has the disadvantage that Paths. Using Java 8: if Files. Wendel Wendel 2, 22 22 silver badges 27 27 bronze badges. Typically, you'll want something like Files.
MikeC I wonder which method gets called without the second argument. The Docu doesn't even show any information about that. PowerFlower: There is only one Files. Without passing the second argument, it still calls the same method. The second argument is varargs variable and can pass 0 or more LinkOptions. To physically create a file you have to explicitly create it: f. Does pearl's -e also ensure that the application "can read" the file? There are multiple ways to achieve this.
In case of just for existence. Change Language. Related Articles. Table of Contents. Improve Article. Save Article. Like Article. Attention reader! Get hold of all the important Java Foundation and Collections concepts with the Fundamentals of Java and Java Collections Course at a student-friendly price and become industry ready. Next Java. File Class in Java. Recommended Articles. Article Contributed By :. Easy Normal Medium Hard Expert.
Writing code in comment?
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