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 and Description
StringUtil()

Method Summary

Modifier and Type	Method and Description
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 padded with leading spaces so that it's length is length.
static void	main(String[] args)
static String	parseCharacterEncoding(String contentType) Parse the character encoding from the specified content type header.
static String	resolveEncodingAlias(String encoding)
static String	rightPad(String s, int length) Returns a copy of s 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 padded with trailing spaces so that it's length is length. Strings already length characters long or longer are not altered.

leftPad

public static String leftPad(String s,
                             int length)

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

toHexString

public static String toHexString(byte[] buf)

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

Parameters:

buf -

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

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.

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

parseCharacterEncoding

public static String parseCharacterEncoding(String contentType)

Parse the character encoding from the specified content type header. If the content type is null, or there is no explicit character encoding, null is returned.
This method was copy from org.apache.catalina.util.RequestUtil is licensed under the Apache License, Version 2.0 (the "License").

Parameters:

contentType - a content type header

isEmpty

public static boolean isEmpty(String str)

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

resolveEncodingAlias

public static String resolveEncodingAlias(String encoding)

main

public static void main(String[] args)