I'm trying to extract the content of a zip file contained into my jarfile (in fact it contains a few files that can be edited and need to be extracted at the first use, even if there is no internet connection). I can extract a single file from my jar if I know its name using MyMainClass.getResource("myfile.zip") but I would like to extract its content without having to extract myfile.zip and delete it after. Is it possible with java 8?
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 ?
I have something like this:
File.txt/directory/directory/Main.java
and all of it is packed in a zip.
What is the correct path to File.txt in Main.java?
The short answer is that you cannot do this: there is (currently) no approach that allows you to point to a file inside a zip file. What you can do is read the zip file as a stream and then take the file that you need. For that, I would refer you to Read Content from Files which are inside Zip file.
I'm trying to generate a zip file with java.util.zip API and I haven't found any way to set zip entry as read only file. I would like to create a new ZIP archive, put files inside it and set read only flag for all those files that appear inside of the ZIP file (on Windows platform).
I am aware that java.util.zip API works with Streams instead of File objects (File object has method setReadonly()).
I also tried with Apache Commons Compress API and haven't found solution as well.
Please help!
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.