org.nd4j.util

Class StringUtils

java.lang.Object

org.nd4j.util.StringUtils

public class StringUtils
extends java.lang.Object

General string utils - adapted from Apache Hadoop StringUtils, with modifications

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	StringUtils.TraditionalBinaryPrefix The traditional binary prefixes, kilo, mega, ..., exa, which can be represented by a 64-bit integer.

Field Summary

Fields

Modifier and Type	Field and Description
static char	COMMA
static java.lang.String[]	emptyStringArray
static char	ESCAPE_CHAR

Constructor Summary

Constructors

Constructor and Description
StringUtils()

Method Summary

Modifier and Type	Method and Description
static java.lang.String	arrayToString(java.lang.String[] strs) Given an array of strings, return a comma-separated list of its elements.
static java.lang.String	byteDesc(long len)
static java.lang.String	byteToHexString(byte b) Convert a byte to a hex string.
static java.lang.String	byteToHexString(byte[] bytes) Same as byteToHexString(bytes, 0, bytes.length).
static java.lang.String	byteToHexString(byte[] bytes, int start, int end) Given an array of bytes it will convert the bytes to a hex string representation of the bytes
static java.lang.String	camelize(java.lang.String s) Convert SOME_STUFF to SomeStuff
static boolean	equalsIgnoreCase(java.lang.String s1, java.lang.String s2) Compare strings locale-freely by using String#equalsIgnoreCase.
static java.lang.String	escapeHTML(java.lang.String string) Escapes HTML Special characters present in the string.
static java.lang.String	escapeString(java.lang.String str) Escape commas in the string using the default escape char
static java.lang.String	escapeString(java.lang.String str, char escapeChar, char charToEscape) Escape charToEscape in the string with the escape char escapeChar
static java.lang.String	escapeString(java.lang.String str, char escapeChar, char[] charsToEscape)
static int	findNext(java.lang.String str, char separator, char escapeChar, int start, java.lang.StringBuilder split) Finds the first occurrence of the separator character ignoring the escaped separators starting from the index.
static java.lang.String	format(java.lang.String format, java.lang.Object... objects) The same as String.format(Locale.ENGLISH, format, objects).
static java.lang.String	formatPercent(double fraction, int decimalPlaces) Format a percentage for presentation to the user.
static java.lang.String	formatTime(long timeDiff) Given the time in long milliseconds, returns a String in the format Xhrs, Ymins, Z sec.
static java.lang.String	formatTimeDiff(long finishTime, long startTime) Given a finish and start time in long milliseconds, returns a String in the format Xhrs, Ymins, Z sec, for the time difference between two times.
static java.lang.String	formatTimeSortable(long timeDiff) Given the time in long milliseconds, returns a String in the sortable format Xhrs, Ymins, Zsec.
static java.lang.String	getFormattedTimeWithDiff(java.lang.String formattedFinishTime, long finishTime, long startTime) Formats time in ms and appends difference (finishTime - startTime) as returned by formatTimeDiff().
static java.lang.String	getStackTrace(java.lang.Thread t) Get stack trace for a given thread.
static java.util.Collection<java.lang.String>	getStringCollection(java.lang.String str) Returns a collection of strings.
static java.util.Collection<java.lang.String>	getStringCollection(java.lang.String str, java.lang.String delim) Returns a collection of strings.
static java.lang.String[]	getStrings(java.lang.String str) Returns an arraylist of strings.
static java.lang.String[]	getStrings(java.lang.String str, java.lang.String delim) Returns an arraylist of strings.
static java.util.Collection<java.lang.String>	getTrimmedStringCollection(java.lang.String str) Splits a comma separated value String, trimming leading and trailing whitespace on each value.
static java.lang.String[]	getTrimmedStrings(java.lang.String str) Splits a comma or newline separated value String, trimming leading and trailing whitespace on each value.
static byte[]	hexStringToByte(java.lang.String hex) Given a hexstring this will return the byte array corresponding to the string
static java.lang.String	humanReadableInt(long number) Deprecated. use StringUtils.TraditionalBinaryPrefix.long2String(long, String, int).
static boolean	isAlpha(java.lang.String str) Checks if the String contains only unicode letters.
static java.lang.String	join(char separator, java.lang.Iterable<?> strings) Concatenates strings, using whitespaces as separator.
static java.lang.String	join(java.lang.CharSequence separator, java.lang.Iterable<?> strings) Concatenates strings, using a separator.
static java.lang.String	join(java.lang.CharSequence separator, java.lang.String[] strings) Concatenates strings, using a separator.
static java.lang.String	join(char separator, java.lang.String[] strings)
static java.lang.String	join(java.lang.Iterable<java.lang.String> strings) Concatenates strings, using whitespaces as separator.
static java.lang.String	limitDecimalTo2(double d) Deprecated. use StringUtils.format("%.2f", d).
static java.lang.String	replaceTokens(java.lang.String template, java.util.regex.Pattern pattern, java.util.Map<java.lang.String,java.lang.String> replacements) Matches a template string against a pattern, replaces matched tokens with the supplied replacements, and returns the result.
static java.lang.String	simpleHostname(java.lang.String fullHostname) Given a full hostname, return the word upto the first dot.
static java.lang.String[]	split(java.lang.String str) Split a string using the default separator
static java.lang.String[]	split(java.lang.String str, char separator) Split a string using the given separator, with no escaping performed.
static java.lang.String[]	split(java.lang.String str, char escapeChar, char separator) Split a string using the given separator
static java.lang.String[]	splitOnCharWithQuoting(java.lang.String s, char splitChar, char quoteChar, char escapeChar) This function splits the String s into multiple Strings using the splitChar.
static java.lang.String	stringifyException(java.lang.Throwable e) Make a string representation of the exception.
static java.util.concurrent.TimeUnit	stringToTimeUnit(java.lang.String str)
static java.net.URI[]	stringToURI(java.lang.String[] str)
static java.lang.String	timeUnitToString(long time, java.util.concurrent.TimeUnit unit)
static java.lang.String	toLowerCase(java.lang.String str) Converts all of the characters in this String to lower case with Locale.ENGLISH.
static java.lang.String	toUpperCase(java.lang.String str) Converts all of the characters in this String to upper case with Locale.ENGLISH.
static java.lang.String	unEscapeString(java.lang.String str) Unescape commas in the string using the default escape char
static java.lang.String	unEscapeString(java.lang.String str, char escapeChar, char charToEscape) Unescape charToEscape in the string with the escape char escapeChar
static java.lang.String	unEscapeString(java.lang.String str, char escapeChar, char[] charsToEscape)
static java.lang.String	uriToString(java.net.URI[] uris)

Methods inherited from class java.lang.Object

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

Field Detail

emptyStringArray

public static final java.lang.String[] emptyStringArray

COMMA

public static final char COMMA

See Also:

Constant Field Values

ESCAPE_CHAR

public static final char ESCAPE_CHAR

See Also:

Constant Field Values

Constructor Detail

StringUtils

public StringUtils()

Method Detail

stringifyException

public static java.lang.String stringifyException(java.lang.Throwable e)

Make a string representation of the exception.

Parameters:

e - The exception to stringify

Returns:

A string with exception name and call stack.

simpleHostname

public static java.lang.String simpleHostname(java.lang.String fullHostname)

Given a full hostname, return the word upto the first dot.

Parameters:

fullHostname - the full hostname

Returns:

the hostname to the first dot

humanReadableInt

@Deprecated
public static java.lang.String humanReadableInt(long number)

Deprecated. use StringUtils.TraditionalBinaryPrefix.long2String(long, String, int).

Given an integer, return a string that is in an approximate, but human readable format.

Parameters:

number - the number to format

Returns:

a human readable form of the integer

format

public static java.lang.String format(java.lang.String format,
                                      java.lang.Object... objects)

The same as String.format(Locale.ENGLISH, format, objects).

formatPercent

public static java.lang.String formatPercent(double fraction,
                                             int decimalPlaces)

Format a percentage for presentation to the user.

Parameters:

fraction - the percentage as a fraction, e.g. 0.1 = 10%

decimalPlaces - the number of decimal places

Returns:

a string representation of the percentage

arrayToString

public static java.lang.String arrayToString(java.lang.String[] strs)

Given an array of strings, return a comma-separated list of its elements.

Parameters:

strs - Array of strings

Returns:

Empty string if strs.length is 0, comma separated list of strings otherwise

byteToHexString

public static java.lang.String byteToHexString(byte[] bytes,
                                               int start,
                                               int end)

Given an array of bytes it will convert the bytes to a hex string representation of the bytes

Parameters:

bytes -

start - start index, inclusively

end - end index, exclusively

Returns:

hex string representation of the byte array

byteToHexString

public static java.lang.String byteToHexString(byte[] bytes)

Same as byteToHexString(bytes, 0, bytes.length).

byteToHexString

public static java.lang.String byteToHexString(byte b)

Convert a byte to a hex string.

Parameters:

b - byte

Returns:

byte's hex value as a String

See Also:

byteToHexString(byte[]), byteToHexString(byte[], int, int)

hexStringToByte

public static byte[] hexStringToByte(java.lang.String hex)

Given a hexstring this will return the byte array corresponding to the string

Parameters:

hex - the hex String array

Returns:

a byte array that is a hex string representation of the given string. The size of the byte array is therefore hex.length/2

uriToString

public static java.lang.String uriToString(java.net.URI[] uris)

Parameters:

uris -

stringToURI

public static java.net.URI[] stringToURI(java.lang.String[] str)

Parameters:

str - The string array to be parsed into an URI array.

Returns:

null if str is null, else the URI array equivalent to str.

Throws:

java.lang.IllegalArgumentException - If any string in str violates RFC 2396.

formatTimeDiff

public static java.lang.String formatTimeDiff(long finishTime,
                                              long startTime)

Given a finish and start time in long milliseconds, returns a String in the format Xhrs, Ymins, Z sec, for the time difference between two times. If finish time comes before start time then negative valeus of X, Y and Z wil return.

Parameters:

finishTime - finish time

startTime - start time

formatTime

public static java.lang.String formatTime(long timeDiff)

Given the time in long milliseconds, returns a String in the format Xhrs, Ymins, Z sec.

Parameters:

timeDiff - The time difference to format

formatTimeSortable

public static java.lang.String formatTimeSortable(long timeDiff)

Given the time in long milliseconds, returns a String in the sortable format Xhrs, Ymins, Zsec. X, Y, and Z are always two-digit. If the time is more than 100 hours ,it is displayed as 99hrs, 59mins, 59sec.

Parameters:

timeDiff - The time difference to format

getFormattedTimeWithDiff

public static java.lang.String getFormattedTimeWithDiff(java.lang.String formattedFinishTime,
                                                        long finishTime,
                                                        long startTime)

Formats time in ms and appends difference (finishTime - startTime) as returned by formatTimeDiff(). If finish time is 0, empty string is returned, if start time is 0 then difference is not appended to return value.

Parameters:

formattedFinishTime - formattedFinishTime to use

finishTime - finish time

startTime - start time

Returns:

formatted value.

getStrings

public static java.lang.String[] getStrings(java.lang.String str)

Returns an arraylist of strings.

Parameters:

str - the comma separated string values

Returns:

the arraylist of the comma separated string values

getStrings

public static java.lang.String[] getStrings(java.lang.String str,
                                            java.lang.String delim)

Returns an arraylist of strings.

Parameters:

str - the string values

delim - delimiter to separate the values

Returns:

the arraylist of the separated string values

getStringCollection

public static java.util.Collection<java.lang.String> getStringCollection(java.lang.String str)

Returns a collection of strings.

Parameters:

str - comma separated string values

Returns:

an ArrayList of string values

getStringCollection

public static java.util.Collection<java.lang.String> getStringCollection(java.lang.String str,
                                                                         java.lang.String delim)

Returns a collection of strings.

Parameters:

str - String to parse

delim - delimiter to separate the values

Returns:

Collection of parsed elements.

getTrimmedStringCollection

public static java.util.Collection<java.lang.String> getTrimmedStringCollection(java.lang.String str)

Splits a comma separated value String, trimming leading and trailing whitespace on each value. Duplicate and empty values are removed.

Parameters:

str - a comma separated with values, may be null

Returns:

a Collection of String values, empty Collection if null String input

getTrimmedStrings

public static java.lang.String[] getTrimmedStrings(java.lang.String str)

Splits a comma or newline separated value String, trimming leading and trailing whitespace on each value.

Parameters:

str - a comma or newline separated String with values, may be null

Returns:

an array of String values, empty array if null String input

split

public static java.lang.String[] split(java.lang.String str)

Split a string using the default separator

Parameters:

str - a string that may have escaped separator

Returns:

an array of strings

split

public static java.lang.String[] split(java.lang.String str,
                                       char escapeChar,
                                       char separator)

Split a string using the given separator

Parameters:

str - a string that may have escaped separator

escapeChar - a char that be used to escape the separator

separator - a separator char

Returns:

an array of strings

split

public static java.lang.String[] split(java.lang.String str,
                                       char separator)

Split a string using the given separator, with no escaping performed.

Parameters:

str - a string to be split. Note that this may not be null.

separator - a separator char

Returns:

an array of strings

findNext

public static int findNext(java.lang.String str,
                           char separator,
                           char escapeChar,
                           int start,
                           java.lang.StringBuilder split)

Finds the first occurrence of the separator character ignoring the escaped separators starting from the index. Note the substring between the index and the position of the separator is passed.

Parameters:

str - the source string

separator - the character to find

escapeChar - character used to escape

start - from where to search

split - used to pass back the extracted string

splitOnCharWithQuoting

public static java.lang.String[] splitOnCharWithQuoting(java.lang.String s,
                                                        char splitChar,
                                                        char quoteChar,
                                                        char escapeChar)

This function splits the String s into multiple Strings using the splitChar. However, it provides an quoting facility: it is possible to quote strings with the quoteChar. If the quoteChar occurs within the quotedExpression, it must be prefaced by the escapeChar

Parameters:

s - The String to split

splitChar -

quoteChar -

Returns:

An array of Strings that s is split into

escapeString

public static java.lang.String escapeString(java.lang.String str)

Escape commas in the string using the default escape char

Parameters:

str - a string

Returns:

an escaped string

escapeString

public static java.lang.String escapeString(java.lang.String str,
                                            char escapeChar,
                                            char charToEscape)

Escape charToEscape in the string with the escape char escapeChar

Parameters:

str - string

escapeChar - escape char

charToEscape - the char to be escaped

Returns:

an escaped string

escapeString

public static java.lang.String escapeString(java.lang.String str,
                                            char escapeChar,
                                            char[] charsToEscape)

Parameters:

charsToEscape - array of characters to be escaped

unEscapeString

public static java.lang.String unEscapeString(java.lang.String str)

Unescape commas in the string using the default escape char

Parameters:

str - a string

Returns:

an unescaped string

unEscapeString

public static java.lang.String unEscapeString(java.lang.String str,
                                              char escapeChar,
                                              char charToEscape)

Unescape charToEscape in the string with the escape char escapeChar

Parameters:

str - string

escapeChar - escape char

charToEscape - the escaped char

Returns:

an unescaped string

unEscapeString

public static java.lang.String unEscapeString(java.lang.String str,
                                              char escapeChar,
                                              char[] charsToEscape)

Parameters:

charsToEscape - array of characters to unescape

escapeHTML

public static java.lang.String escapeHTML(java.lang.String string)

Escapes HTML Special characters present in the string.

Parameters:

string -

Returns:

HTML Escaped String representation

byteDesc

public static java.lang.String byteDesc(long len)

Returns:

a byte description of the given long interger value.

limitDecimalTo2

@Deprecated
public static java.lang.String limitDecimalTo2(double d)

Deprecated. use StringUtils.format("%.2f", d).

join

public static java.lang.String join(java.lang.CharSequence separator,
                                    java.lang.Iterable<?> strings)

Concatenates strings, using a separator.

Parameters:

separator - Separator to join with.

strings - Strings to join.

join

public static java.lang.String join(java.lang.Iterable<java.lang.String> strings)

Concatenates strings, using whitespaces as separator.

Parameters:

strings - Strings to join.

join

public static java.lang.String join(char separator,
                                    java.lang.Iterable<?> strings)

Concatenates strings, using whitespaces as separator.

Parameters:

strings - Strings to join.

join

public static java.lang.String join(java.lang.CharSequence separator,
                                    java.lang.String[] strings)

Concatenates strings, using a separator.

Parameters:

separator - to join with

strings - to join

Returns:

the joined string

join

public static java.lang.String join(char separator,
                                    java.lang.String[] strings)

camelize

public static java.lang.String camelize(java.lang.String s)

Convert SOME_STUFF to SomeStuff

Parameters:

s - input string

Returns:

camelized string

replaceTokens

public static java.lang.String replaceTokens(java.lang.String template,
                                             java.util.regex.Pattern pattern,
                                             java.util.Map<java.lang.String,java.lang.String> replacements)

Matches a template string against a pattern, replaces matched tokens with the supplied replacements, and returns the result. The regular expression must use a capturing group. The value of the first capturing group is used to look up the replacement. If no replacement is found for the token, then it is replaced with the empty string. For example, assume template is "%foo%_%bar%_%baz%", pattern is "%(.*?)%", and replacements contains 2 entries, mapping "foo" to "zoo" and "baz" to "zaz". The result returned would be "zoo__zaz".

Parameters:

template - String template to receive replacements

pattern - Pattern to match for identifying tokens, must use a capturing group

replacements - Map mapping tokens identified by the capturing group to their replacement values

Returns:

String template with replacements

getStackTrace

public static java.lang.String getStackTrace(java.lang.Thread t)

Get stack trace for a given thread.

toLowerCase

public static java.lang.String toLowerCase(java.lang.String str)

Converts all of the characters in this String to lower case with Locale.ENGLISH.

Parameters:

str - string to be converted

Returns:

the str, converted to lowercase.

toUpperCase

public static java.lang.String toUpperCase(java.lang.String str)

Converts all of the characters in this String to upper case with Locale.ENGLISH.

Parameters:

str - string to be converted

Returns:

the str, converted to uppercase.

equalsIgnoreCase

public static boolean equalsIgnoreCase(java.lang.String s1,
                                       java.lang.String s2)

Compare strings locale-freely by using String#equalsIgnoreCase.

Parameters:

s1 - Non-null string to be converted

s2 - string to be converted

Returns:

the str, converted to uppercase.

isAlpha

public static boolean isAlpha(java.lang.String str)

Checks if the String contains only unicode letters.

null will return false. An empty String (length()=0) will return true.

 StringUtils.isAlpha(null)   = false
 StringUtils.isAlpha("")     = true
 StringUtils.isAlpha("  ")   = false
 StringUtils.isAlpha("abc")  = true
 StringUtils.isAlpha("ab2c") = false
 StringUtils.isAlpha("ab-c") = false
 

Parameters:

str - the String to check, may be null

Returns:

true if only contains letters, and is non-null

timeUnitToString

public static java.lang.String timeUnitToString(long time,
                                                java.util.concurrent.TimeUnit unit)

stringToTimeUnit

public static java.util.concurrent.TimeUnit stringToTimeUnit(java.lang.String str)