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Zipping single file in a single zip without creating a folder

In java most of the zipping apis zips the single file by creating a folder.
For example in windows if we choose to right click-->Winzip-->Add to selected_file_name.zip it creates selected_file_name.zip and if we extract we directly get file rather than a folder and within folder a file.
After extracting by selecting a extract to here only file should come rather than a folder and then a file within that.
Can we do the same using any java api ?

How to stop creating thumbs.db files in compression using java

I am trying to compress a folder to zip and extract the same folder using java. When i zipped or unzipped the folder the files which are in the folder compressed and extracted successfully. But a Thumbs.db file is creating with in the folder.
I want to delete/avoid the Thumbs.db files before/after compressing to zip or extracting from zip programmatically.
Is it possible in java ?

Thumbs.db is usually a file with the system and hidden attributes (see attrib.exe ) and therefore invisible in the Explorer (unless you set the Explorer to show all files including system files).
When you extract the file you should set it's attributes accordingly.
How to set a file attribute using Java is already described here: https://stackoverflow.com/a/36465283/150978

programmatically creating links in Zip file - java

I am creating a zip file using ZipOutputStream. There will also be a manifest file (a csv file) which will have links to the entries in the Zip file. How do I programmatically create links for the zip entries ?

If you keep track of all the entries while you write them, you should be able to add another entry containing the "links" (but how should a csv link to a file? Please specify what you try to achieve).
If you intend to use the file under windows, you could create .lnk files programmatically; but this only works for one file per link. On unices, ZipOutputStream cannot create symlinks, but ZipFileSystem can.

How can I add a directory (tree of files) into a zip?

How can I add/modify/delete/merge recursive directory in a zip file (in Java) without file system?
Do I have to respect the order of zip entries?
Yes, I know merging directories is very complex job..

If you need to add whole directory with files to zip archive recursively only by Java core efforts, then you can use good example from Mkyong's blog. If you need to append files to existing zip-file, the you should use a link from #McDowell's comment: Appending files to a zip file with Java

There is no simple answer, your going to need to write a faire bit of code. You can't use the JDK ZipFile class, as that only supports reading zip files.
Instead use Commons Compress. Have a look at the examples and the zip documentation to get going.
Basically you'll need to open an input zip file, and an output zip file. Read each entry in tern, and decide whether to write it to the output, transform and write, add a new entry, or skip it, . When you get to the end close both zip files.
When processing a zip file, it's not really recursive, as all the entries are just a linear list with a path and filename. The recursive part comes when a zip contains a zip, and that is quite easy to handle.

Split zip with truezip

Referring to this post I have zipped and unzipped folders successfully - TrueZip - How to decompress inner jar/zip files without expanding them as directories?
Is there any way to split zip into parts using truezip, similar to 7z which allows us to create parts of zip file?

No, ZIP file splitting/spanning is not supported by TrueZIP.