Check if Java File Name and Path is valid

In this tutorial see various ways to check if Java File Name and Path is valid.

1. Check if File Exists
We should check if the file to be created exists using file.exists()
2. Make use of the Java 7 java.nio.file.Paths class.
```
public static boolean isPathValid(String path) {

            try {

                Paths.get(path);

            } catch (InvalidPathException ex) {
                return false;
            }

            return true;
        }
```
The Paths.get(path) method returns a path. However if the path is not valid, then it throws InvalidPathException.
For example Path.get("C://test.txt") will return true while Path.get("C://tes?t.txt") will throw an InvalidPathException.
3. Make use of the File.getCanonicalPath()
File.getCanonicalPath() will throw IOException if the file path contains invalid filename like "?", "|".
```
public static boolean isValidFilePath(String path) {
    File f = new File(path);
    try {
       f.getCanonicalPath();
       return true;
    }
    catch (IOException e) {
       return false;
    }
  }
```
isValidFilePath("C://test.txt") will throw true above while isValidFilePath("C://te?st.txt") will return false.

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