org.apache.commons.compress.archivers.zip
Class ZipUtil

java.lang.Object
  org.apache.commons.compress.archivers.zip.ZipUtil

public abstract class ZipUtil
extends Object

Utility class for handling DOS and Java time conversions.

ZipUtil

public ZipUtil()

toDosTime

public static ZipLong toDosTime(Date time)

Convert a Date object to a DOS date/time field.

Parameters:

time - the Date to convert

Returns:

the date as a ZipLong

toDosTime

public static byte[] toDosTime(long t)

Convert a Date object to a DOS date/time field.

Stolen from InfoZip's fileio.c

Parameters:

t - number of milliseconds since the epoch

Returns:

the date as a byte array

adjustToLong

public static long adjustToLong(int i)

Assumes a negative integer really is a positive integer that has wrapped around and re-creates the original value.

Parameters:

i - the value to treat as unsigned int.

Returns:

the unsigned int as a long.

reverse

public static byte[] reverse(byte[] array)

Reverses a byte[] array. Reverses in-place (thus provided array is mutated), but also returns same for convenience.

Parameters:

array - to reverse (mutated in-place, but also returned for convenience).

Returns:

the reversed array (mutated in-place, but also returned for convenience).

Since:

1.5

signedByteToUnsignedInt

public static int signedByteToUnsignedInt(byte b)

Converts a signed byte into an unsigned integer representation (e.g., -1 becomes 255).

Parameters:

b - byte to convert to int

Returns:

int representation of the provided byte

Since:

1.5

unsignedIntToSignedByte

public static byte unsignedIntToSignedByte(int i)

Converts an unsigned integer to a signed byte (e.g., 255 becomes -1).

Parameters:

i - integer to convert to byte

Returns:

byte representation of the provided int

Throws:

IllegalArgumentException - if the provided integer is not inside the range [0,255].

Since:

1.5

fromDosTime

public static Date fromDosTime(ZipLong zipDosTime)

Convert a DOS date/time field to a Date object.

Parameters:

zipDosTime - contains the stored DOS time.

Returns:

a Date instance corresponding to the given time.

dosToJavaTime

public static long dosToJavaTime(long dosTime)

Converts DOS time to Java time (number of milliseconds since epoch).