Package net.i2p.data

Class DataHelper

java.lang.Object

net.i2p.data.DataHelper

public class DataHelper
extends Object

Defines some simple IO routines for dealing with marshalling data structures

Author:

jrandom

Field Summary

Fields

Modifier and Type	Field	Description
static final int	DATE_LENGTH
static final int	HIGH_COMPRESSION	Appx.
static final int	MAX_COMPRESSION	Appx.
static final int	MAX_UNCOMPRESSED
static final int	MEDIUM_COMPRESSION	New default as of 0.9.47
static final int	NO_COMPRESSION

Constructor Summary

Constructors

Constructor	Description
DataHelper()

Method Summary

Modifier and Type	Method	Description
static final int	compareTo(byte[] lhs, byte[] rhs)	Big endian compare, treats bytes as unsigned.
static byte[]	compress(byte[] orig)	Compress the data and return a new GZIP compressed byte array.
static byte[]	compress(byte[] orig, int offset, int size)	Compress the data and return a new GZIP compressed byte array.
static byte[]	compress(byte[] orig, int offset, int size, int level)	Compress the data and return a new GZIP compressed byte array.
static void	copy(InputStream in, OutputStream out)	Copy in to out.
static byte[]	decompress(byte[] orig)	Decompress the GZIP compressed data (returning null on error).
static byte[]	decompress(byte[] orig, int offset, int length)	Decompress the GZIP compressed data (returning null on error).
static final boolean	eq(byte[] lhs, byte[] rhs)	Run a comparison on the byte arrays, byte by byte.
static final boolean	eq(byte[] lhs, int offsetLeft, byte[] rhs, int offsetRight, int length)	Unlike eq(byte[], byte[]), this returns false if either lhs or rhs is null.
static final boolean	eq(byte lhs, byte rhs)	Deprecated. inefficient
static final boolean	eq(int lhs, int rhs)	Deprecated. inefficient
static final boolean	eq(long lhs, long rhs)	Deprecated. inefficient
static final boolean	eq(Object lhs, Object rhs)	Helper util to compare two objects, including null handling.
static final boolean	eq(Collection<?> lhs, Collection<?> rhs)	Run a deep comparison across the two collections.
static final boolean	eqCT(byte[] lhs, int offsetLeft, byte[] rhs, int offsetRight, int length)	Unlike eq(), this throws NPE if either lhs or rhs is null.
static String	escapeHTML(String unescaped)	Escape a string for inclusion in HTML
static String	formatDate(long now)	The default formatting for date, current locale, local time zone.
static String	formatDuration(long ms)	NOTE: formatDuration2() recommended in most cases for readability
static String	formatDuration2(double ms)	Like formatDuration2(long) but with microsec and nanosec also.
static String	formatDuration2(long ms)	Like formatDuration but with a non-breaking space after the number, 0 is unitless, and the unit is translated.
static String	formatSize(long bytes)	This is binary, i.e.
static String	formatSize2(long bytes)	This is binary, i.e.
static String	formatSize2(long bytes, boolean nonBreaking)	This is binary, i.e.
static String	formatSize2Decimal(long bytes)	This is decimal, i.e.
static String	formatSize2Decimal(long bytes, boolean nonBreaking)	This is decimal, i.e.
static String	formatTime(long now)	The default formatting for date/time, current locale, local time zone.
static Date	fromDate(byte[] src, int offset)
static final byte[]	fromHexString(String val)	Deprecated. unused
static long	fromLong(byte[] src, int offset, int numBytes)	Big endian.
static long	fromLong8(byte[] src, int offset)	Big endian.
static long	fromLongLE(byte[] src, int offset, int numBytes)	Little endian, i.e.
static int	fromProperties(byte[] source, int offset, Properties target)	Reads the props from the byte array and puts them in the Properties target See readProperties() for the format.
static byte[]	getASCII(String orig)	Roughly the same as orig.getBytes("ISO-8859-1") but much faster and will not throw an exception.
static String	getUTF8(byte[] orig)	Same as new String(orig, "UTF-8") but throws an unchecked RuntimeException instead of an UnsupportedEncodingException if no UTF-8, for ease of use.
static String	getUTF8(byte[] orig, int offset, int len)	Same as new String(orig, "UTF-8") but throws an unchecked RuntimeException instead of an UnsupportedEncodingException if no UTF-8, for ease of use.
static byte[]	getUTF8(String orig)	Same as orig.getBytes("UTF-8") but throws an unchecked RuntimeException instead of an UnsupportedEncodingException if no UTF-8, for ease of use.
static byte[]	getUTF8(StringBuffer orig)	Deprecated. unused
static int	hashCode(byte[] b)	Calculate the hashcode of the byte array, using 0 for null
static int	hashCode(Object obj)	Calculate the hashcode of the object, using 0 for null
static int	hashCode(Collection<?> col)	Calculate the hashcode of the collection, using 0 for null
static int	hashCode(Date obj)	Calculate the hashcode of the date, using 0 for null
static void	loadProps(Properties props, File file)	A more efficient Properties.load Some of the other differences: - UTF-8 encoding, not ISO-8859-1 - No escaping! This does not process or drop backslashes - '#' or ';' starts a comment line, but '!' does not - Leading whitespace is not trimmed - '=' is the only key-termination character (not ':' or whitespace) As of 0.9.10, an empty value is allowed.
static void	loadProps(Properties props, File file, boolean forceLowerCase)
static void	loadProps(Properties props, InputStream inStr)
static void	loadProps(Properties props, InputStream inStr, boolean forceLowerCase)
static int	read(InputStream in, byte[] target)	This is different than InputStream.read(target), in that it does repeated reads until the full data is received.
static int	read(InputStream in, byte[] target, int offset, int length)	WARNING - This is different than InputStream.read(target, offset, length) for a nonzero offset, in that it returns the new offset (== old offset + length).
static Date	readDate(InputStream in)	Read in a date from the stream as specified by the I2P data structure spec.
static String	readLine(InputStream in)	Read a newline delimited line from the stream, returning the line (without the newline), or null if EOF reached on an empty line Warning - strips \n but not \r Warning - 8KB line length limit as of 0.7.13, @throws IOException if exceeded Warning - not UTF-8
static boolean	readLine(InputStream in, StringBuilder buf)	Read in a line, placing it into the buffer (excluding the newline).
static boolean	readLine(InputStream in, StringBuilder buf, MessageDigest hash)	update the hash along the way Warning - strips \n but not \r Warning - 8KB line length limit as of 0.7.13, @throws IOException if exceeded Warning - not UTF-8
static String	readLine(InputStream in, MessageDigest hash)	update the hash along the way Warning - strips \n but not \r Warning - 8KB line length limit as of 0.7.13, @throws IOException if exceeded Warning - not UTF-8
static long	readLong(InputStream rawStream, int numBytes)	Read the stream for an integer as defined by the I2P data structure specification.
static Properties	readProperties(InputStream rawStream)	Read a mapping from the stream, as defined by the I2P data structure spec, and store it into a Properties object.
static Properties	readProperties(InputStream rawStream, Properties props)	Ditto, load into an existing properties As of 0.9.18, throws DataFormatException on duplicate key
static String	readString(InputStream in)	Read in a string from the stream as specified by the I2P data structure spec.
static void	replace(StringBuilder buf, String from, String to)	Replace all instances of "from" with "to" in the StringBuilder buf.
static void	skip(InputStream in, long n)	This is different than InputStream.skip(), in that it does repeated reads until the full amount is skipped.
static <T> void	sort(List<T> list, Comparator<? super T> c)	Same as Collections.sort(), but guaranteed not to throw an IllegalArgumentException if the sort is unstable.
static <T> void	sort(T[] a, Comparator<? super T> c)	Same as Arrays.sort(), but guaranteed not to throw an IllegalArgumentException if the sort is unstable.
static String[]	split(String s, String regex)	Same as s.split(regex) but caches the compiled pattern for speed.
static String[]	split(String s, String regex, int limit)	Same as s.split(regex, limit) but caches the compiled pattern for speed.
static void	storeProps(Properties props, File file)	Writes the props to the file, unsorted (unless props is an OrderedProperties) Note that this does not escape the \r or \n that are unescaped in loadProps() above.
static String	stripHTML(String orig)	Strip out any HTML (simply removing any less than / greater than symbols)
static void	toDate(byte[] target, int offset, long when)
static byte[]	toDate(Date date)	Deprecated. unused
static String	toDecimalString(byte[] buf, int len)	Deprecated. unused
static final String	toHexString(byte[] data)	Lower-case hex without leading zeros.
static void	toLong(byte[] target, int offset, int numBytes, long value)	Big endian.
static byte[]	toLong(int numBytes, long value)	Big endian.
static void	toLong8(byte[] target, int offset, long value)	Big endian.
static void	toLongLE(byte[] target, int offset, int numBytes, long value)	Little endian, i.e.
static int	toProperties(byte[] target, int offset, Properties props)
static byte[]	toProperties(Properties opts)	Writes the props to returned byte array, not sorted (unless the opts param is an OrderedProperties) Strings will be UTF-8 encoded in the byte array.
static String	toString(byte[] buf)	Lower-case hex with leading zeros.
static String	toString(byte[] buf, int len)	Lower-case hex with leading zeros.
static String	toString(Collection<?> col)	Pretty print the collection
static String	toString(Map<?,?> options)	Pretty print the mapping, unsorted (unless the options param is an OrderedProperties)
static String	toString(Properties options)	Pretty print the mapping, unsorted (unless the options param is an OrderedProperties)
static void	write(OutputStream out, byte[] data, MessageDigest hash)	update the hash along the way
static void	writeDate(OutputStream out, Date date)	Write out a date to the stream as specified by the I2P data structure spec.
static void	writeLong(OutputStream rawStream, int numBytes, long value)	Write an integer as defined by the I2P data structure specification to the stream.
static void	writeProperties(OutputStream rawStream, Properties props)	Write a mapping to the stream, as defined by the I2P data structure spec, and store it into a Properties object.
static void	writeProperties(OutputStream rawStream, Properties props, boolean utf8)	Writes the props to the stream, sorted by property name.
static void	writeProperties(OutputStream rawStream, Properties props, boolean utf8, boolean sort)	Writes the props to the stream, sorted by property name if sort == true or if props is an OrderedProperties.
static void	writeString(OutputStream out, String string)	Write out a string to the stream as specified by the I2P data structure spec.
static void	writeStringUTF8(OutputStream out, String string)	Write out a string to the stream as specified by the I2P data structure spec.
static final byte[]	xor(byte[] lhs, byte[] rhs)
static final void	xor(byte[] lhs, int startLeft, byte[] rhs, int startRight, byte[] out, int startOut, int len)	xor the lhs with the rhs, storing the result in out.

Methods inherited from class java.lang.Object

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

Field Details

DATE_LENGTH

public static final int DATE_LENGTH

See Also:

• Constant Field Values

MAX_UNCOMPRESSED

public static final int MAX_UNCOMPRESSED

See Also:

• Constant Field Values

MAX_COMPRESSION

public static final int MAX_COMPRESSION

Appx. 30% slower, 2.5% smaller than MEDIUM_COMPRESSION

See Also:

• Constant Field Values

HIGH_COMPRESSION

public static final int HIGH_COMPRESSION

Appx. 15% slower, 1.5% smaller than MEDIUM_COMPRESSION

Since:

0.9.47

See Also:

• Constant Field Values

MEDIUM_COMPRESSION

public static final int MEDIUM_COMPRESSION

New default as of 0.9.47

Since:

0.9.47

See Also:

• Constant Field Values

NO_COMPRESSION

public static final int NO_COMPRESSION

See Also:

• Constant Field Values

Constructor Details

DataHelper

public DataHelper()

Method Details

readProperties

public static Properties readProperties(InputStream rawStream)
                                 throws DataFormatException,
IOException

Read a mapping from the stream, as defined by the I2P data structure spec, and store it into a Properties object. A mapping is a set of key / value pairs. It starts with a 2 byte Integer (ala readLong(rawStream, 2)) defining how many bytes make up the mapping. After that comes that many bytes making up a set of UTF-8 encoded characters. The characters are organized as key=value;. The key is a String (ala readString(rawStream)) unique as a key within the current mapping that does not include the UTF-8 characters '=' or ';'. After the key comes the literal UTF-8 character '='. After that comes a String (ala readString(rawStream)) for the value. Finally after that comes the literal UTF-8 character ';'. This key=value; is repeated until there are no more bytes (not characters!) left as defined by the first two byte integer. As of 0.9.18, throws DataFormatException on duplicate key

Parameters:

rawStream - stream to read the mapping from

Returns:

an OrderedProperties

Throws:

DataFormatException - if the format is invalid

IOException - if there is a problem reading the data

readProperties

public static Properties readProperties(InputStream rawStream,
 Properties props)
                                 throws DataFormatException,
IOException

Ditto, load into an existing properties As of 0.9.18, throws DataFormatException on duplicate key

Parameters:

rawStream - stream to read the mapping from

props - The Properties to load into. As of 0.9.38, if null, a new OrderedProperties will be created.

Returns:

the parameter props, or (as of 0.9.38) a new OrderedProperties if props is null, and an immutable EmptyProperties if empty.

Throws:

DataFormatException - if the format is invalid

IOException - if there is a problem reading the data

Since:

0.8.13

writeProperties

public static void writeProperties(OutputStream rawStream,
 Properties props)
                            throws DataFormatException,
IOException

Write a mapping to the stream, as defined by the I2P data structure spec, and store it into a Properties object. See readProperties for the format. Output is sorted by property name. Property keys and values must not contain '=' or ';', this is not checked and they are not escaped Keys and values must be 255 bytes or less, Formatted length must not exceed 65535 bytes Properties from the defaults table of props (if any) are not written out by this method.

Parameters:

rawStream - stream to write to

props - properties to write out, may be null

Throws:

DataFormatException - if there is not enough valid data to write out, or a length limit is exceeded

IOException - if there is an IO error writing out the data

writeProperties

public static void writeProperties(OutputStream rawStream,
 Properties props,
 boolean utf8)
                            throws DataFormatException,
IOException

Writes the props to the stream, sorted by property name. See readProperties() for the format. Property keys and values must not contain '=' or ';', this is not checked and they are not escaped Keys and values must be 255 bytes or less, Formatted length must not exceed 65535 bytes Properties from the defaults table of props (if any) are not written out by this method. jrandom disabled UTF-8 in mid-2004, for performance reasons, i.e. slow foo.getBytes("UTF-8") Re-enable it so we can pass UTF-8 tunnel names through the I2CP SessionConfig. Use utf8 = false for RouterAddress (fast, non UTF-8) Use utf8 = true for SessionConfig (slow, UTF-8)

Parameters:

props - source may be null

Throws:

DataFormatException - if a length limit is exceeded

IOException

writeProperties

public static void writeProperties(OutputStream rawStream,
 Properties props,
 boolean utf8,
 boolean sort)
                            throws DataFormatException,
IOException

Writes the props to the stream, sorted by property name if sort == true or if props is an OrderedProperties. See readProperties() for the format. Property keys and values must not contain '=' or ';', this is not checked and they are not escaped Keys and values must be 255 bytes or less, Formatted length must not exceed 65535 bytes Properties from the defaults table of props (if any) are not written out by this method. jrandom disabled UTF-8 in mid-2004, for performance reasons, i.e. slow foo.getBytes("UTF-8") Re-enable it so we can pass UTF-8 tunnel names through the I2CP SessionConfig. Use utf8 = false for RouterAddress (fast, non UTF-8) Use utf8 = true for SessionConfig (slow, UTF-8)

Parameters:

props - source may be null

sort - should we sort the properties? (set to false if already sorted, e.g. OrderedProperties)

Throws:

DataFormatException - if any string is over 255 bytes long, or if the total length (not including the two length bytes) is greater than 65535 bytes.

IOException

Since:

0.8.7

toProperties

public static int toProperties(byte[] target,
 int offset,
 Properties props)
                        throws DataFormatException,
IOException

Throws:

DataFormatException

IOException

fromProperties

public static int fromProperties(byte[] source,
 int offset,
 Properties target)
                          throws DataFormatException

Reads the props from the byte array and puts them in the Properties target See readProperties() for the format. Warning - confusing method name, Properties is the target. Strings must be UTF-8 encoded in the byte array. As of 0.9.18, throws DataFormatException on duplicate key

Parameters:

source - source

target - returned Properties

Returns:

new offset

Throws:

DataFormatException

toProperties

public static byte[] toProperties(Properties opts)
                           throws DataFormatException

Writes the props to returned byte array, not sorted (unless the opts param is an OrderedProperties) Strings will be UTF-8 encoded in the byte array. See readProperties() for the format. Property keys and values must not contain '=' or ';', this is not checked and they are not escaped Keys and values must be 255 bytes or less, Formatted length must not exceed 65535 bytes Warning - confusing method name, Properties is the source. Properties from the defaults table of props (if any) are not written out by this method.

Throws:

DataFormatException - if key, value, or total is too long

toString

public static String toString(Properties options)

Pretty print the mapping, unsorted (unless the options param is an OrderedProperties)

toString

public static String toString(Map<?,?> options)

Pretty print the mapping, unsorted (unless the options param is an OrderedProperties)

Since:

0.9.4, as of 0.9.38 supports non-String values

loadProps

public static void loadProps(Properties props,
 File file)
                      throws IOException

A more efficient Properties.load Some of the other differences: - UTF-8 encoding, not ISO-8859-1 - No escaping! This does not process or drop backslashes - '#' or ';' starts a comment line, but '!' does not - Leading whitespace is not trimmed - '=' is the only key-termination character (not ':' or whitespace) As of 0.9.10, an empty value is allowed. As in Java Properties, duplicate keys are allowed, last one wins.

Throws:

IOException

loadProps

public static void loadProps(Properties props,
 File file,
 boolean forceLowerCase)
                      throws IOException

Parameters:

forceLowerCase - if true forces the keys to lower case (not the values)

Throws:

IOException

loadProps

public static void loadProps(Properties props,
 InputStream inStr)
                      throws IOException

Throws:

IOException

loadProps

public static void loadProps(Properties props,
 InputStream inStr,
 boolean forceLowerCase)
                      throws IOException

Parameters:

forceLowerCase - if true forces the keys to lower case (not the values)

Throws:

IOException

storeProps

public static void storeProps(Properties props,
 File file)
                       throws IOException

Writes the props to the file, unsorted (unless props is an OrderedProperties) Note that this does not escape the \r or \n that are unescaped in loadProps() above. As of 0.8.1, file will be mode 600. Properties from the defaults table of props (if any) are not written out by this method. Leading or trailing whitespace in values is not checked but will be trimmed by loadProps()

Throws:

IllegalArgumentException - if a key contains any of "#=\n" or starts with ';', or a value contains '#' or '\n'

IOException

toString

public static String toString(Collection<?> col)

Pretty print the collection

toString

public static String toString(byte[] buf)

Lower-case hex with leading zeros. Use toHexString(byte[]) to not get leading zeros

Parameters:

buf - may be null (returns "")

Returns:

String of length 2*buf.length

toString

public static String toString(byte[] buf,
 int len)

Lower-case hex with leading zeros. Use toHexString(byte[]) to not get leading zeros

Parameters:

buf - may be null

len - number of bytes. If greater than buf.length, additional zeros will be prepended

Returns:

String of length 2*len

toDecimalString

@Deprecated
public static String toDecimalString(byte[] buf,
 int len)

Deprecated.

unused

Positive decimal without leading zeros.

Parameters:

buf - may be null (returns "0")

len - unused

Returns:

(new BigInteger(1, buf)).toString()

toHexString

public static final String toHexString(byte[] data)

Lower-case hex without leading zeros. Use toString(byte[]) to get leading zeros

Parameters:

data - may be null (returns "00")

fromHexString

@Deprecated
public static final byte[] fromHexString(String val)

Deprecated.

unused

Parameters:

val - non-null, may have leading minus sign

Returns:

minimum-length representation (with possible leading 0 byte)

readLong

public static long readLong(InputStream rawStream,
 int numBytes)
                     throws DataFormatException,
IOException

Read the stream for an integer as defined by the I2P data structure specification. Integers are a fixed number of bytes (numBytes), stored as unsigned integers in network byte order.

Parameters:

rawStream - stream to read from

numBytes - number of bytes to read and format into a number, 1 to 8

Returns:

number

Throws:

DataFormatException - if negative (only possible if numBytes = 8) (since 0.8.12)

EOFException - since 0.8.2, if there aren't enough bytes to read the number

IOException - if there is an IO error reading the number

writeLong

public static void writeLong(OutputStream rawStream,
 int numBytes,
 long value)
                      throws DataFormatException,
IOException

Write an integer as defined by the I2P data structure specification to the stream. Integers are a fixed number of bytes (numBytes), stored as unsigned integers in network byte order.

Parameters:

rawStream - stream to write to

numBytes - number of bytes to write the number into, 1-8 (padding as necessary)

value - value to write out, non-negative

Throws:

DataFormatException - if value is negative or if numBytes not 1-8

IOException - if there is an IO error writing to the stream

toLong

public static byte[] toLong(int numBytes,
 long value)
                     throws IllegalArgumentException

Big endian.

Parameters:

numBytes - 1-8

value - non-negative

Returns:

an array of length numBytes

Throws:

IllegalArgumentException

toLong

public static void toLong(byte[] target,
 int offset,
 int numBytes,
 long value)
                   throws IllegalArgumentException

Big endian.

Parameters:

numBytes - 1-8

value - non-negative

Throws:

IllegalArgumentException

toLongLE

public static void toLongLE(byte[] target,
 int offset,
 int numBytes,
 long value)

Little endian, i.e. backwards. Not for use in I2P protocols.

Parameters:

numBytes - 1-8

value - non-negative

Since:

0.8.12

fromLong

public static long fromLong(byte[] src,
 int offset,
 int numBytes)

Big endian.

Parameters:

src - if null returns 0

numBytes - 1-8

Returns:

non-negative

Throws:

ArrayIndexOutOfBoundsException

IllegalArgumentException - if negative (only possible if numBytes = 8)

fromLongLE

public static long fromLongLE(byte[] src,
 int offset,
 int numBytes)

Little endian, i.e. backwards. Not for use in I2P protocols.

Parameters:

numBytes - 1-8

Returns:

non-negative

Throws:

ArrayIndexOutOfBoundsException

IllegalArgumentException - if negative (only possible if numBytes = 8)

Since:

0.8.12

fromLong8

public static long fromLong8(byte[] src,
 int offset)

Big endian. Same as fromLong(src, offset, 8) but allows negative result

Throws:

ArrayIndexOutOfBoundsException

Since:

0.9.47 moved from NTCP2Payload

toLong8

public static void toLong8(byte[] target,
 int offset,
 long value)

Big endian. Same as toLong(target, offset, 8, value) but allows negative value

Throws:

ArrayIndexOutOfBoundsException

Since:

0.9.47 moved from NTCP2Payload

readDate

public static Date readDate(InputStream in)
                     throws DataFormatException,
IOException

Read in a date from the stream as specified by the I2P data structure spec. A date is an 8 byte unsigned integer in network byte order specifying the number of milliseconds since midnight on January 1, 1970 in the GMT timezone. If the number is 0, the date is undefined or null. (yes, this means you can't represent midnight on 1/1/1970)

Parameters:

in - stream to read from

Returns:

date read, or null

Throws:

DataFormatException - if the stream doesn't contain a validly formatted date

IOException - if there is an IO error reading the date

writeDate

public static void writeDate(OutputStream out,
 Date date)
                      throws DataFormatException,
IOException

Write out a date to the stream as specified by the I2P data structure spec.

Parameters:

out - stream to write to

date - date to write (can be null)

Throws:

DataFormatException - if the date is not valid

IOException - if there is an IO error writing the date

toDate

@Deprecated
public static byte[] toDate(Date date)
                     throws IllegalArgumentException

Deprecated.

unused

Throws:

IllegalArgumentException

toDate

public static void toDate(byte[] target,
 int offset,
 long when)
                   throws IllegalArgumentException

Throws:

IllegalArgumentException

fromDate

public static Date fromDate(byte[] src,
 int offset)
                     throws DataFormatException

Throws:

DataFormatException

readString

public static String readString(InputStream in)
                         throws DataFormatException,
IOException

Read in a string from the stream as specified by the I2P data structure spec. A string is 1 or more bytes where the first byte is the number of bytes (not characters!) in the string and the remaining 0-255 bytes are the non-null terminated UTF-8 encoded character array.

Parameters:

in - stream to read from

Returns:

UTF-8 string

Throws:

DataFormatException - if the stream doesn't contain a validly formatted string

EOFException - since 0.8.2, if there aren't enough bytes to read the string

IOException - if there is an IO error reading the string

writeString

public static void writeString(OutputStream out,
 String string)
                        throws DataFormatException,
IOException

Write out a string to the stream as specified by the I2P data structure spec. Note that the max size for a string allowed by the spec is 255 bytes. WARNING - this method destroys the encoding, and therefore violates the data structure spec.

Parameters:

out - stream to write string

string - string to write out: null strings are perfectly valid, but strings of excess length will cause a DataFormatException to be thrown

Throws:

DataFormatException - if the string is not valid

IOException - if there is an IO error writing the string

writeStringUTF8

public static void writeStringUTF8(OutputStream out,
 String string)
                            throws DataFormatException,
IOException

Write out a string to the stream as specified by the I2P data structure spec. Note that the max size for a string allowed by the spec is 255 bytes. This method correctly uses UTF-8

Parameters:

out - stream to write string

string - UTF-8 string to write out: null strings are perfectly valid, but strings of excess length will cause a DataFormatException to be thrown

Throws:

DataFormatException - if the string is not valid

IOException - if there is an IO error writing the string

Since:

public since 0.9.26

eq

public static final boolean eq(Object lhs,
 Object rhs)

Helper util to compare two objects, including null handling.

This treats (null == null) as true, and (null == (!null)) as false.

eq

public static final boolean eq(Collection<?> lhs,
 Collection<?> rhs)

Run a deep comparison across the two collections.

This treats (null == null) as true, (null == (!null)) as false, and then comparing each element via eq(object, object).

If the size of the collections are not equal, the comparison returns false. The collection order should be consistent, as this simply iterates across both and compares based on the value of each at each step along the way.

eq

public static final boolean eq(byte[] lhs,
 byte[] rhs)

Run a comparison on the byte arrays, byte by byte.

This treats (null == null) as true, (null == (!null)) as false, and unequal length arrays as false. Variable time.

Returns:

Arrays.equals(lhs, rhs)

eq

@Deprecated
public static final boolean eq(int lhs,
 int rhs)

Deprecated.

inefficient

Compare two integers, really just for consistency.

eq

@Deprecated
public static final boolean eq(long lhs,
 long rhs)

Deprecated.

inefficient

Compare two longs, really just for consistency.

eq

@Deprecated
public static final boolean eq(byte lhs,
 byte rhs)

Deprecated.

inefficient

Compare two bytes, really just for consistency.

eq

public static final boolean eq(byte[] lhs,
 int offsetLeft,
 byte[] rhs,
 int offsetRight,
 int length)

Unlike eq(byte[], byte[]), this returns false if either lhs or rhs is null. Variable time.

Throws:

ArrayIndexOutOfBoundsException - if either array isn't long enough

eqCT

public static final boolean eqCT(byte[] lhs,
 int offsetLeft,
 byte[] rhs,
 int offsetRight,
 int length)

Unlike eq(), this throws NPE if either lhs or rhs is null. Constant time.

Throws:

NullPointerException - if lhs or rhs is null

ArrayIndexOutOfBoundsException - if either array isn't long enough

Since:

0.9.13

compareTo

public static final int compareTo(byte[] lhs,
 byte[] rhs)

Big endian compare, treats bytes as unsigned. Shorter arg is lesser. Args may be null, null is less than non-null. Variable time.

xor

public static final byte[] xor(byte[] lhs,
 byte[] rhs)

Returns:

null if either arg is null or the args are not equal length

xor

public static final void xor(byte[] lhs,
 int startLeft,
 byte[] rhs,
 int startRight,
 byte[] out,
 int startOut,
 int len)

xor the lhs with the rhs, storing the result in out.

Parameters:

lhs - one of the source arrays

startLeft - starting index in the lhs array to begin the xor

rhs - the other source array

startRight - starting index in the rhs array to begin the xor

out - output array

startOut - starting index in the out array to store the result

len - how many bytes into the various arrays to xor

hashCode

public static int hashCode(Object obj)

Calculate the hashcode of the object, using 0 for null

hashCode

public static int hashCode(Date obj)

Calculate the hashcode of the date, using 0 for null

hashCode

public static int hashCode(byte[] b)

Calculate the hashcode of the byte array, using 0 for null

hashCode

public static int hashCode(Collection<?> col)

Calculate the hashcode of the collection, using 0 for null

skip

public static void skip(InputStream in,
 long n)
                 throws IOException

This is different than InputStream.skip(), in that it does repeated reads until the full amount is skipped. To fix findbugs issues with skip(). Guaranteed to skip exactly n bytes or throw an IOE. http://stackoverflow.com/questions/14057720/robust-skipping-of-data-in-a-java-io-inputstream-and-its-subtypes http://stackoverflow.com/questions/11511093/java-inputstream-skip-return-value-near-end-of-file

Throws:

IOException

Since:

0.9.9

read

public static int read(InputStream in,
 byte[] target)
                throws IOException

This is different than InputStream.read(target), in that it does repeated reads until the full data is received. As of 0.9.27, throws EOFException if the full length is not read.

Returns:

target.length

Throws:

EOFException - if the full length is not read (since 0.9.27)

IOException

read

public static int read(InputStream in,
 byte[] target,
 int offset,
 int length)
                throws IOException

WARNING - This is different than InputStream.read(target, offset, length) for a nonzero offset, in that it returns the new offset (== old offset + length). It also does repeated reads until the full data is received. WARNING - Broken for nonzero offset before 0.9.27. As of 0.9.27, throws EOFException if the full length is not read.

Returns:

the new offset (== old offset + length)

Throws:

EOFException - if the full length is not read (since 0.9.27)

IOException

readLine

public static String readLine(InputStream in)
                       throws IOException

Read a newline delimited line from the stream, returning the line (without the newline), or null if EOF reached on an empty line Warning - strips \n but not \r Warning - 8KB line length limit as of 0.7.13, @throws IOException if exceeded Warning - not UTF-8

Returns:

null on EOF

Throws:

IOException

readLine

public static String readLine(InputStream in,
 MessageDigest hash)
                       throws IOException

update the hash along the way Warning - strips \n but not \r Warning - 8KB line length limit as of 0.7.13, @throws IOException if exceeded Warning - not UTF-8

Parameters:

hash - null OK

Returns:

null on EOF

Throws:

IOException

Since:

0.8.8

readLine

public static boolean readLine(InputStream in,
 StringBuilder buf)
                        throws IOException

Read in a line, placing it into the buffer (excluding the newline). Warning - strips \n but not \r Warning - 8KB line length limit as of 0.7.13, @throws IOException if exceeded Warning - not UTF-8

Returns:

true if the line was read, false if eof was reached on an empty line (returns true for non-empty last line without a newline)

Throws:

IOException

readLine

public static boolean readLine(InputStream in,
 StringBuilder buf,
 MessageDigest hash)
                        throws IOException

update the hash along the way Warning - strips \n but not \r Warning - 8KB line length limit as of 0.7.13, @throws IOException if exceeded Warning - not UTF-8

Parameters:

hash - null OK

Returns:

true if the line was read, false if eof was reached on an empty line (returns true for non-empty last line without a newline)

Throws:

IOException

Since:

0.8.8

write

public static void write(OutputStream out,
 byte[] data,
 MessageDigest hash)
                  throws IOException

update the hash along the way

Throws:

IOException

Since:

0.8.8

formatDuration

public static String formatDuration(long ms)

NOTE: formatDuration2() recommended in most cases for readability

formatDuration2

public static String formatDuration2(long ms)

Like formatDuration but with a non-breaking space after the number, 0 is unitless, and the unit is translated. This seems consistent with most style guides out there. Use only in HTML. Thresholds are a little lower than in formatDuration() also, as precision is less important in the GUI than in logging. Negative numbers handled correctly.

Since:

0.8.2

formatDuration2

public static String formatDuration2(double ms)

Like formatDuration2(long) but with microsec and nanosec also.

Since:

0.9.19

formatSize

public static String formatSize(long bytes)

This is binary, i.e. multiples of 1024. For decimal, see formatSize2Decimal(). Caller should append 'B' or 'b' as appropriate. No space between the number and the letter. NOTE: formatSize2() recommended in most cases for readability

Returns:

e.g. "123.05Ki"

formatSize2

public static String formatSize2(long bytes)

This is binary, i.e. multiples of 1024. For decimal, see formatSize2Decimal(). Caller should append 'B' or 'b' as appropriate. Like formatSize but with a non-breaking space after the number This seems consistent with most style guides out there. Use only in HTML, and not inside form values (use formatSize2(bytes, false) there instead).

Returns:

e.g. "123.05 Ki"

Since:

0.7.14, uses thin non-breaking space since 0.9.31

formatSize2

public static String formatSize2(long bytes,
 boolean nonBreaking)

This is binary, i.e. multiples of 1024. For decimal, see formatSize2Decimal(). Caller should append 'B' or 'b' as appropriate, Like formatSize but with a space after the number This seems consistent with most style guides out there.

Parameters:

nonBreaking - use an HTML thin non-breaking space ( )

Returns:

e.g. "123.05 Ki" or "123.05 Ki"

Since:

0.9.31

formatSize2Decimal

public static String formatSize2Decimal(long bytes)

This is decimal, i.e. multiples of 1000. For binary, see formatSize2(). Caller should append 'B' or 'b' as appropriate. Like formatSize but with a space after the number This seems consistent with most style guides out there.

Returns:

e.g. "123.05 K"

Since:

0.9.34

formatSize2Decimal

public static String formatSize2Decimal(long bytes,
 boolean nonBreaking)

This is decimal, i.e. multiples of 1000. For binary, see formatSize2(). Caller should append 'B' or 'b' as appropriate. Like formatSize but with a space after the number This seems consistent with most style guides out there.

Parameters:

nonBreaking - use an HTML thin non-breaking space ( )

Returns:

e.g. "123.05 K" or "123.05 K"

Since:

0.9.34

formatDate

public static String formatDate(long now)

The default formatting for date, current locale, local time zone. Warning - NOT UTC! Examples: en: Aug 30, 2019 de: 30.08.2019

Since:

0.9.43

formatTime

public static String formatTime(long now)

The default formatting for date/time, current locale, local time zone. Warning - NOT UTC! Examples: en: Aug 30, 2019 12:38 PM de: 30.08.2019 12:38

Since:

0.9.43

stripHTML

public static String stripHTML(String orig)

Strip out any HTML (simply removing any less than / greater than symbols)

Parameters:

orig - may be null, returns empty string if null

escapeHTML

public static String escapeHTML(String unescaped)

Escape a string for inclusion in HTML

Parameters:

unescaped - the unescaped string, may be null

Returns:

the escaped string, or null if null is passed in

compress

public static byte[] compress(byte[] orig)

Compress the data and return a new GZIP compressed byte array. The compressed data conforms to RFC 1952, with a 10-byte gzip header and a 8-byte gzip checksum footer. Prior to 0.9.29, this would return a zero-length output for a zero-length input. As of 0.9.29, output is valid for a zero-length input also. As of 0.9.47, this uses a level of MEDIUM_COMPRESSION, which is a good space/speed tradeoff. Prior to that, it used MAX_COMPRESSION.

Returns:

null if orig is null

Throws:

IllegalArgumentException - if input size is over 40KB

IllegalStateException - on compression failure, as of 0.9.29

compress

public static byte[] compress(byte[] orig,
 int offset,
 int size)

Compress the data and return a new GZIP compressed byte array. The compressed data conforms to RFC 1952, with a 10-byte gzip header and a 8-byte gzip checksum footer. Prior to 0.9.29, this would return a zero-length output for a zero-length input. As of 0.9.29, output is valid for a zero-length input also. As of 0.9.47, this uses a level of MEDIUM_COMPRESSION, which is a good space/speed tradeoff. Prior to that, it used MAX_COMPRESSION.

Returns:

null if orig is null

Throws:

IllegalArgumentException - if size is over 40KB

IllegalStateException - on compression failure, as of 0.9.29

compress

public static byte[] compress(byte[] orig,
 int offset,
 int size,
 int level)

Compress the data and return a new GZIP compressed byte array. The compressed data conforms to RFC 1952, with a 10-byte gzip header and a 8-byte gzip checksum footer. Prior to 0.9.29, this would return a zero-length output for a zero-length input. As of 0.9.29, output is valid for a zero-length input also.

Parameters:

level - the compression level, 0 to 9

Returns:

null if orig is null

Throws:

IllegalArgumentException - if size is over 40KB

IllegalStateException - on compression failure, as of 0.9.29

decompress

public static byte[] decompress(byte[] orig)
                         throws IOException

Decompress the GZIP compressed data (returning null on error).

Returns:

null if orig is null

Throws:

IOException - if uncompressed is over 40 KB, or on a decompression error

decompress

public static byte[] decompress(byte[] orig,
 int offset,
 int length)
                         throws IOException

Decompress the GZIP compressed data (returning null on error).

Returns:

null if orig is null

Throws:

IOException - if uncompressed is over 40 KB, or on a decompression error

getUTF8

public static byte[] getUTF8(String orig)

Same as orig.getBytes("UTF-8") but throws an unchecked RuntimeException instead of an UnsupportedEncodingException if no UTF-8, for ease of use.

Returns:

null if orig is null

Throws:

RuntimeException

getUTF8

@Deprecated
public static byte[] getUTF8(StringBuffer orig)

Deprecated.

unused

Same as orig.getBytes("UTF-8") but throws an unchecked RuntimeException instead of an UnsupportedEncodingException if no UTF-8, for ease of use.

Returns:

null if orig is null

Throws:

RuntimeException

getUTF8

public static String getUTF8(byte[] orig)

Same as new String(orig, "UTF-8") but throws an unchecked RuntimeException instead of an UnsupportedEncodingException if no UTF-8, for ease of use. Used by Syndie.

Returns:

null if orig is null

Throws:

RuntimeException

getUTF8

public static String getUTF8(byte[] orig,
 int offset,
 int len)

Same as new String(orig, "UTF-8") but throws an unchecked RuntimeException instead of an UnsupportedEncodingException if no UTF-8, for ease of use.

Returns:

null if orig is null

Throws:

RuntimeException

getASCII

public static byte[] getASCII(String orig)

Roughly the same as orig.getBytes("ISO-8859-1") but much faster and will not throw an exception. Warning - misnamed, converts to ISO-8859-1.

Parameters:

orig - non-null, truncates to 8-bit chars

Since:

0.9.5

split

public static String[] split(String s,
 String regex)

Same as s.split(regex) but caches the compiled pattern for speed. This saves about 10 microseconds (Bulldozer) on subsequent invocations. Note: For an input "" this returns [""], not a zero-length array. This is the same behavior as String.split().

Parameters:

s - non-null

regex - non-null, don't forget to enclose multiple choices with []

Throws:

PatternSyntaxException - unchecked

Since:

0.9.24

split

public static String[] split(String s,
 String regex,
 int limit)

Same as s.split(regex, limit) but caches the compiled pattern for speed. This saves about 10 microseconds (Bulldozer) on subsequent invocations. Note: For an input "" this returns [""], not a zero-length array. This is the same behavior as String.split().

Parameters:

s - non-null

regex - non-null, don't forget to enclose multiple choices with []

limit - result threshold

Throws:

PatternSyntaxException - unchecked

Since:

0.9.24

copy

public static void copy(InputStream in,
 OutputStream out)
                 throws IOException

Copy in to out. Caller MUST close the streams.

Parameters:

in - non-null

out - non-null

Throws:

IOException

Since:

0.9.29

sort

public static <T> void sort(List<T> list,
 Comparator<? super T> c)

Same as Collections.sort(), but guaranteed not to throw an IllegalArgumentException if the sort is unstable. As of Java 7, TimSort will throw an IAE if the underlying sort order changes during the sort. This catches the IAE, retries once, and then returns. If an IAE is thrown twice, this method will return, with the list possibly unsorted.

Parameters:

list - the list to be sorted.

c - the comparator to determine the order of the list. A null value indicates that the elements' natural ordering should be used.

Since:

0.9.34

sort

public static <T> void sort(T[] a,
 Comparator<? super T> c)

Same as Arrays.sort(), but guaranteed not to throw an IllegalArgumentException if the sort is unstable. As of Java 7, TimSort will throw an IAE if the underlying sort order changes during the sort. This catches the IAE, retries once, and then returns. If an IAE is thrown twice, this method will return, with the array possibly unsorted.

Parameters:

a - the array to be sorted.

c - the comparator to determine the order of the array. A null value indicates that the elements' natural ordering should be used.

Since:

0.9.34

replace

public static void replace(StringBuilder buf,
 String from,
 String to)

Replace all instances of "from" with "to" in the StringBuilder buf. Same as String.replace(), but in-memory with no object churn, as long as "to" is equal size or smaller than "from", or buf has capacity. Use for large Strings or for multiple replacements in a row.

Parameters:

buf - contains the string to be searched

from - the string to be replaced

to - the replacement string

Since:

0.9.34