Package org.apache.nutch.util

Class StringUtil

java.lang.Object

org.apache.nutch.util.StringUtil

public class StringUtil
extends Object

A collection of String processing utility methods.

Constructor Summary

Constructors

Constructor	Description
StringUtil()

Method Summary

Modifier and Type	Method	Description
static String	cleanField(String value)	Simple character substitution which cleans/removes all � chars from a given String.
static byte[]	fromHexString(String text)	Convert a String containing consecutive (no inside whitespace) hexadecimal digits into a corresponding byte array.
static boolean	isEmpty(String str)	Checks if a string is empty (ie is null or empty).
static String	leftPad(String s, int length)	Returns a copy of s (left padded) with leading spaces so that it's length is length.
static void	main(String[] args)
static String	mask(String str)	Mask sensitive strings - passwords, etc.
static String	mask(String str, char mask)	Mask sensitive strings - passwords, etc.
static String	mask(String str, Pattern pattern, char mask)	Mask sensitive strings - passwords, etc.
static String	rightPad(String s, int length)	Returns a copy of s (right padded) with trailing spaces so that it's length is length.
static String	toHexString(byte[] buf)	Convenience call for toHexString(byte[], String, int), where sep = null; lineLen = Integer.MAX_VALUE.
static String	toHexString(byte[] buf, String sep, int lineLen)	Get a text representation of a byte[] as hexadecimal String, where each pair of hexadecimal digits corresponds to consecutive bytes in the array.

Methods inherited from class java.lang.Object

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

Constructor Detail

StringUtil

public StringUtil()

Method Detail

rightPad

public static String rightPad(String s,
                              int length)

Returns a copy of s (right padded) with trailing spaces so that it's length is length. Strings already length characters long or longer are not altered.

Parameters:

s - input string to be copied and processed

length - desired final length of padded string

Returns:

the resulting padded string

leftPad

public static String leftPad(String s,
                             int length)

Returns a copy of s (left padded) with leading spaces so that it's length is length. Strings already length characters long or longer are not altered.

Parameters:

s - input string to be copied and processed

length - desired final length of padded string

Returns:

the resulting padded string

toHexString

public static String toHexString(byte[] buf)

Convenience call for toHexString(byte[], String, int), where sep = null; lineLen = Integer.MAX_VALUE.

Parameters:

buf - input data for which to generate a hex string

Returns:

the hex string

toHexString

public static String toHexString(byte[] buf,
                                 String sep,
                                 int lineLen)

Get a text representation of a byte[] as hexadecimal String, where each pair of hexadecimal digits corresponds to consecutive bytes in the array.

Parameters:

buf - input data for which to generate a hex string

sep - separate every pair of hexadecimal digits with this separator, or null if no separation is needed.

lineLen - break the output String into lines containing output for lineLen bytes.

Returns:

the hex string

fromHexString

public static byte[] fromHexString(String text)

Convert a String containing consecutive (no inside whitespace) hexadecimal digits into a corresponding byte array. If the number of digits is not even, a '0' will be appended in the front of the String prior to conversion. Leading and trailing whitespace is ignored.

Parameters:

text - input text

Returns:

converted byte array, or null if unable to convert

isEmpty

public static boolean isEmpty(String str)

Checks if a string is empty (ie is null or empty).

Parameters:

str - the String to check for being empty or null

Returns:

true if empty or null, false otherwise

cleanField

public static String cleanField(String value)

Simple character substitution which cleans/removes all � chars from a given String.

Parameters:

value - the String to clean

Returns:

substituted cleaned string

mask

public static String mask(String str)

Mask sensitive strings - passwords, etc.

Parameters:

str - input string

Returns:

the masked string, all characters replaced by *

mask

public static String mask(String str,
                          char mask)

Mask sensitive strings - passwords, etc.

Parameters:

str - input string

mask - char used for masking

Returns:

the masked string, all characters replaced by the mask character

mask

public static String mask(String str,
                          Pattern pattern,
                          char mask)

Mask sensitive strings - passwords, etc.

Parameters:

str - input string

pattern - pattern which defines capturing groups to be masked in input

mask - char used for masking

Returns:

the masked string, all characters matched in capturing groups of the pattern replaced by the mask character

main

public static void main(String[] args)