com.android.tools.build.apkzlib.zip.utils

Class LittleEndianUtils

java.lang.Object

com.android.tools.build.apkzlib.zip.utils.LittleEndianUtils

public class LittleEndianUtils
extends java.lang.Object

Utilities to read and write 16 and 32 bit integers with support for little-endian encoding, as used in zip files. Zip files actually use unsigned data types. We use Java's native (signed) data types but will use long (64 bit) to ensure we can fit the whole range.

Method Summary

Modifier and Type	Method and Description
static int	readUnsigned2Le(java.nio.ByteBuffer bytes) Reads 2 bytes in little-endian format and converts them into a 16-bit value.
static long	readUnsigned4Le(java.nio.ByteBuffer bytes) Reads 4 bytes in little-endian format and converts them into a 32-bit value.
static void	writeUnsigned2Le(java.nio.ByteBuffer output, int value) Writes 2 bytes in little-endian format, converting them from a 16-bit value.
static void	writeUnsigned4Le(java.nio.ByteBuffer output, long value) Writes 4 bytes in little-endian format, converting them from a 32-bit value.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

readUnsigned4Le

public static long readUnsigned4Le(java.nio.ByteBuffer bytes)
                            throws java.io.IOException

Reads 4 bytes in little-endian format and converts them into a 32-bit value.

Parameters:

bytes - from where should the bytes be read; the first 4 bytes of the source will be read

Returns:

the 32-bit value

Throws:

java.io.IOException - failed to read the value

readUnsigned2Le

public static int readUnsigned2Le(java.nio.ByteBuffer bytes)
                           throws java.io.IOException

Reads 2 bytes in little-endian format and converts them into a 16-bit value.

Parameters:

bytes - from where should the bytes be read; the first 2 bytes of the source will be read

Returns:

the 16-bit value

Throws:

java.io.IOException - failed to read the value

writeUnsigned4Le

public static void writeUnsigned4Le(java.nio.ByteBuffer output,
                                    long value)
                             throws java.io.IOException

Writes 4 bytes in little-endian format, converting them from a 32-bit value.

Parameters:

output - the output stream where the bytes will be written

value - the 32-bit value to convert

Throws:

java.io.IOException - failed to write the value data

writeUnsigned2Le

public static void writeUnsigned2Le(java.nio.ByteBuffer output,
                                    int value)
                             throws java.io.IOException

Writes 2 bytes in little-endian format, converting them from a 16-bit value.

Parameters:

output - the output stream where the bytes will be written

value - the 16-bit value to convert

Throws:

java.io.IOException - failed to write the value data