- java.util.zip Package Classes
- java.util.zip - Home
- java.util.zip - Adler32
- java.util.zip - CheckedInputStream
- java.util.zip - CheckedOutputStream
- java.util.zip - CRC32
- java.util.zip - Deflater
- java.util.zip - DeflaterInputStream
- java.util.zip - DeflaterOutputStream
- java.util.zip - GZIPInputStream
- java.util.zip - GZIPOutputStream
- java.util.zip - Inflater
- java.util.zip - InflaterInputStream
- java.util.zip - InflaterOutputStream
- java.util.zip - ZipEntry
- java.util.zip - ZipFile
- java.util.zip - ZipInputStream
- java.util.zip - ZipOutputStream
- java.util.zip Package Extras
- java.util.zip - Exceptions
- java.util.zip - Error
- java.util.zip Useful Resources
- java.util.zip - Quick Guide
- java.util.zip - Useful Resources
- java.util.zip - Discussion
java.util.zip.ZipEntry.getCompressedSize() Method Example
Description
The java.util.zip.ZipEntry.getCompressedSize() method returns the size of the compressed entry data, or -1 if not known. In the case of a stored entry, the compressed size will be the same as the uncompressed size of the entry.
Declaration
Following is the declaration for java.util.zip.ZipEntry.getCompressedSize() method.
public long getCompressedSize()
Returns
the size of the compressed entry data, or -1 if not known
Pre-requisite
Create a file Hello.txt in D:> test > directory with the following content.
This is an example.
Example
The following example shows the usage of java.util.zip.ZipEntry.getCompressedSize() method.
package com.tutorialspoint; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.util.Date; import java.util.Enumeration; import java.util.zip.Adler32; import java.util.zip.CheckedOutputStream; import java.util.zip.ZipEntry; import java.util.zip.ZipFile; import java.util.zip.ZipOutputStream; public class ZipEntryDemo { private static String SOURCE_FILE = "D:\\test\\Hello.txt"; private static String TARGET_FILE = "D:\\test\\Hello.zip"; public static void main(String[] args) { try { createZipFile(); readZipFile(); } catch(IOException ioe) { System.out.println("IOException : " + ioe); } } private static void createZipFile() throws IOException{ FileOutputStream fout = new FileOutputStream(TARGET_FILE); CheckedOutputStream checksum = new CheckedOutputStream(fout, new Adler32()); ZipOutputStream zout = new ZipOutputStream(checksum); FileInputStream fin = new FileInputStream(SOURCE_FILE); ZipEntry zipEntry = new ZipEntry(SOURCE_FILE); zout.putNextEntry(zipEntry); int length; byte[] buffer = new byte[1024]; while((length = fin.read(buffer)) > 0) { zout.write(buffer, 0, length); } zout.closeEntry(); fin.close(); zout.close(); } private static void readZipFile() throws IOException{ final ZipFile file = new ZipFile(TARGET_FILE); System.out.println("Iterating over zip file : " + TARGET_FILE); try { final Enumeration<? extends ZipEntry> entries = file.entries(); while (entries.hasMoreElements()) { final ZipEntry entry = entries.nextElement(); System.out.printf("File: %s Size %d Modified on %TD %n", entry.getName(), entry.getSize(), new Date(entry.getTime())); System.out.println(entry.getCompressedSize()); extractFile(entry, file.getInputStream(entry)); } System.out.printf("Zip file %s extracted successfully.", SOURCE_FILE); } finally { file.close(); } } private static void extractFile(final ZipEntry entry, InputStream is) throws IOException { FileOutputStream fos = null; try { fos = new FileOutputStream(entry.getName()); final byte[] buf = new byte[1024]; int read = 0; int length; while ((length = is.read(buf, 0, buf.length)) >= 0) { fos.write(buf, 0, length); } } catch (IOException ioex) { fos.close(); } } }
Let us compile and run the above program, this will produce the following result −
Iterating over zip file : D:\test\Hello.zip File: D:\test\Hello.txt Size 19 Modified on 05/20/17 19 Zip file D:\test\Hello.txt extracted successfully.Print
javazip_zipentry.htm
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