How to create Uncompressed Zip archive in Java

Question

I am using the Zip utility package of Java and wanted to know how to create a zip file with no compression at all. Setting the level to 0 doesn\'t help. Is this right?

Answer 1

FYI:

In JDK Source of the method [java.util.zip.ZipOutputStream.setLevel(int)]:

public void setLevel(int level) {
    def.setLevel(level);
}

It simply redirect the compression level setting to the field variable [def], which is an instance of [java.util.zip.Deflater].

And in the source code of the class [java.util.zip.Deflater]:

/**
 * Compression level for no compression.
 */
public static final int NO_COMPRESSION = 0;

/**
 * Compression level for fastest compression.
 */
public static final int BEST_SPEED = 1;

/**
 * Compression level for best compression.
 */
public static final int BEST_COMPRESSION = 9;

/**
 * Default compression level.
 */
public static final int DEFAULT_COMPRESSION = -1;

So, I think it will be more readable if you use the constant value [Deflater.NO_COMPRESSION]:

zipOut.setMethod(ZipOutputStream.DEFLATED);
zipOut.setLevel(Deflater.NO_COMPRESSION);