How does ZipInputStream.getNextEntry() work?

Question

Say we have code like:

File file = new File("zip1.zip");
ZipInputStream zis = new ZipInputStream(new FileInputStream(file));

Let's assume you have a .zip file that contains the following:

• zip1.zip
  • hello.c
  • world.java
  • folder1
    • foo.c
    • bar.java
  • foobar.c

How would zis.getNextEntry() iterate through that?

Would it return hello.c, world.java, folder1, foobar.c and completely ignore the files in folder1?

Or would it return hello.c, world.java, folder1, foo.c, bar.java, and then foobar.c?

Would it even return folder1 since it's technically a folder and not a file?

Thanks!

Answer 1

Yes. It will print the folder name too, since it's also an entry within the zip. It will also print in the same order as it is displayed inside the zip. You can use below test to verify your output.

public class TestZipOrder {
    @Test
    public void testZipOrder() throws Exception {
        File file = new File("/Project/test.zip");
        ZipInputStream zis = new ZipInputStream(new FileInputStream(file));
        ZipEntry entry = null;
        while ( (entry = zis.getNextEntry()) != null ) {
         System.out.println( entry.getName());
        }
    }
}