Java 17 Recipes

8-12. Uncompressing Files
 Problem
Your application has the requirement to decompress and extract files from a compressed 
.zip file.
 Solution
Using the java.util.zip package, you can open a .zip file and iterate through its 
entries. While traversing the entries, directories can be created for directory entries. The 
following lines of code demonstrate how to perform the decompress and file iteration 
technique, as described.
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public class Ch_8_12_ZipExample {
public static void
main(String[] args) {
Ch_8_12_ZipExample example = new Ch_8_12_ZipExample();
example.start();
}
private void start() {
ZipFile file = null;
try {
file = new ZipFile("file.zip");
FileSystem fileSystem = FileSystems.getDefault();
Enumeration entries = file.entries();
String uncompressedDirectory = "uncompressed/";
Files.createDirectory(fileSystem.getPath(uncompressedDirectory));
while (entries.hasMoreElements()) {
ZipEntry entry = entries.nextElement();
if (entry.isDirectory()) {
System.out.println("Creating Directory:" + 
uncompressedDirectory + entry.getName());
Files.createDirectories(fileSystem.
getPath(uncompressedDirectory +
entry.getName()));
} else {
InputStream is = file.getInputStream(entry);
System.out.println("File :" + entry.getName());
BufferedInputStream bis = new BufferedInputStream(is);
String uncompressedFileName = uncompressedDirectory + entry.
getName();
Path uncompressedFilePath = fileSystem.
getPath(uncompressedFileName);
Files.createFile(uncompressedFilePath);
try (FileOutputStream fileOutput = new FileOutputStream(uncompr
essedFileName)) {
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327
while (bis.available() > 0) {
fileOutput.write(bis.read());
}
}
System.out.println("Written :" + entry.getName());
}
}
} catch (IOException e) {
e.printStackTrace();
}
}