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Can I use File.createTempFile() to create a file with a non-random name

I want to create a temporary file (that goes away when the application closes) with a specific name. I'm using this code:
f = File.createTempFile("tmp", ".txt", new File("D:/"));
This creates something like D:\tmp4501156806082176909.txt. I want just D:\tmp.txt. How can I do this?

In this case, don't use createTempFile. The point of createTempFile is to generate the "garbage" name in order to avoid name colisions.
You should use File.createNewFile() or simply write to the file. Whichever is more appropriate for your use case. You can then call File.deleteOnExit() to get the VM to look after cleaning up the file.

If you want to create just tmp.txt, then just create the file using createNewFile(), instead of createTempFile(). createTempFile is used to create temporary files that should not have the same name when created over and over.
Also have a look at this post which shows a very simple way to create files.
Taken the post mentioned above:
String path = "C:"+File.separator+"hello"+File.separator+"hi.txt";
//(use relative path for Unix systems)
File f = new File(path);
//(works for both Windows and Linux)
f.mkdirs();
f.createNewFile();

try regex
fileName = fileName.replaceAll("\\d", "");

How to change file path location in java.io.File object [duplicate]

This question already has answers here:
What is meant by immutable?
(17 answers)
Closed 3 years ago.
The question says it all.
I have a File object which is pointing to /home/user/filename1.
If I call file.getAbsolutePath() then it would return /home/user/filename1
My question is that -
Can we change the path inside file object to a different location?
If yes, then how?
Thanks

"Instances of the File class are immutable; that is, once created, the abstract pathname represented by a File object will never change. "
From the File javadoc.

I had developed a code to rename the file and I have to save the file in the same location recursively. I think the below code helps you out upto some extent. I have to replace "-a" in my filename and save it in the same folder. If needed in place of "destPath" you can give the destination path of your string path. I think this might help you.
File oldfile =new File(file.getAbsolutePath());
String origPath = file.getCanonicalPath();
String destPath = origPath.replace(file.getName(),"");
String destFile = file.getName();
String n_destFile = destFile.replace("-a", "");
File newfile =new File(destPath+n_destFile);

A file is internally nothing else other then a string holding the path to the file. So no this is not possible. Why would you even want to do something like this? Unless you have moved the file to another location?

As someone noted before, File is immutable as many of java API classes. Maybe what you want is to copy a file from somewhere to some other place? Have in mind that a File object has no actual binding to the contents of the file, and will not allow you modifying or moving it.
Have a look at Apache Commons IO
http://commons.apache.org/proper/commons-io/apidocs/org/apache/commons/io/IOUtils.html
Here you have a useful library to deal with files.

Java - create file and dir

Assume final String fname = "/dir1/dir2/fname.ext". I do not wish to parse the string recursively in order to create the directories if they do not exist, and only then write to a file. I wish to use the given string, fname, for creating the directories and file if each of which does not exist.

This is the code you are looking for:
File myFile = new File("/dir1/dir2/fname.ext");
myFile.getParentFile().mkdirs();
// do your writing being sure the parent directories exist.

You can use mkdirs to create the path.
File f = new File("/dir1/dir2/fname.ext");
f.getParentFile().mkdirs();
And then work on the file itself.

Create a java file inside a package

Currently, my plugin creates a java file in my project(IProject). But I want that java file within a specified Package. How to do it.
IFile sampleFile = parentFolder.getFile("Sample.java");
if(!sampleFile.exists()) FileInputStream fileStream = new FileInputStream("C:\Users\Uma\Desktop\treasureHunt\Application.java"); sampleFile.create(fileStream, false, null);
This is my current piece of code.
How can I create the sampleFile within a package. For example: in package com.mdh.se as com.mdh.se.Sample.java

If you have a "package" (e.g. "com.mdh.se") then you'll have a corresponding subdirectory (for example, "c:\users\uma\desktop\treasurehunt\com\mdh\se"). Simply write your file there.

I think, that the only thing you need to do is to create folders representing your package structure. So your path should look like C:\Users\Uma\Desktop\treasureHunt\com\mdh\se\Sample.java for your example.

You can get a special file inside the package by calling
java.net.URL imgURL = ResourceManager.class.getResource( "ResourceManager.class" );
From these URL you can extract the directory, the file is placed.
A new file you can create with
new File(directory,filename);

Create all directories up to a point?

I need to be able to build all directories up to and including the directory specified by my File object. For example, suppose I have something like this:
File file = new File( "/var/a/b/c/d/" );
But only /var/ exists. I need a method that builds up to d, and I was wondering if there was a method in a java io library somewhere that does this already.

mkdirs() in java.io.File does the trick.
File file = new File("/var/a/b/c/d");
file.mkdirs();

File.mkdirs()