Class StringUtils

java.lang.Object

org.greenrobot.essentials.StringUtils

public class StringUtils
extends Object

Utilities for working with strings like splitting, joining, url-encoding, hex, and digests.

Field Summary

Fields

Modifier and Type	Field	Description
private static final char[]	HEX_CHARS

Constructor Summary

Constructors

Constructor	Description
StringUtils()

Method Summary

Modifier and Type	Method	Description
static String	decodeUrl(String stringToDecode)	URL-Decodes a given string using UTF-8.
static String	decodeUrlIso(String stringToDecode)	URL-Decodes a given string using ISO-8859-1.
static String	digest(String string, String digestAlgo, String encoding)	Generates a digest (hex string) for the given string
static String	ellipsize(String text, int maxLength)	Cuts the string at the end if it's longer than maxLength and appends "..." to it.
static String	ellipsize(String text, int maxLength, String end)	Cuts the string at the end if it's longer than maxLength and appends the given end string to it.
static String	encodeUrl(String stringToEncode)	URL-Encodes a given string using UTF-8 (some web pages have problems with UTF-8 and umlauts, consider encodeUrlIso(String) also).
static String	encodeUrlIso(String stringToEncode)	URL-encodes a given string using ISO-8859-1, which may work better with web pages and umlauts compared to UTF-8.
static List<String>	findLinesContaining(String text, String searchText)
static String	hex(byte[] bytes)
static String	join(int[] array, String separator)	Joins the given ints using the given separator into a single string.
static String	join(Iterable<?> iterable, String separator)	Joins the given iterable objects using the given separator into a single string.
static String	join(String[] array, String separator)	Joins the given Strings using the given separator into a single string.
static String	md5(String stringToEncode)	Generates the MD5 digest (32 hex characters) for a given String based on UTF-8.
static byte[]	parseHex(String hex)
static int	parseHexDigit(char c)
static String	resolveEntity(String entity)	Simple HTML/XML entity resolving: Only supports unicode entities and a very limited number text represented entities (apos, quot, gt, lt, and amp).
static String	sha1(String stringToEncode)	Generates the SHA-1 digest (40 hex characters) for a given String based on UTF-8.
static String	sha256(String stringToEncode)	Generates the SHA-256 digest (64 hex characters) for a given String based on UTF-8.
static String[]	split(String string, char delimiter)	Splits a String based on a single character, which is usually faster than regex-based String.split().
static String[]	splitLines(String text, boolean skipEmptyLines)

Methods inherited from class Object

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

Field Details

HEX_CHARS

private static final char[] HEX_CHARS

Constructor Details

StringUtils

public StringUtils()

Method Details

split

public static String[] split(String string,
 char delimiter)

Splits a String based on a single character, which is usually faster than regex-based String.split(). NOTE: split("AA;BB;;", ';') == ["AA", "BB", "", ""], this may be different from String.split()

encodeUrl

public static String encodeUrl(String stringToEncode)

URL-Encodes a given string using UTF-8 (some web pages have problems with UTF-8 and umlauts, consider encodeUrlIso(String) also). No UnsupportedEncodingException to handle as it is dealt with in this method.

encodeUrlIso

public static String encodeUrlIso(String stringToEncode)

URL-encodes a given string using ISO-8859-1, which may work better with web pages and umlauts compared to UTF-8. No UnsupportedEncodingException to handle as it is dealt with in this method.

decodeUrl

public static String decodeUrl(String stringToDecode)

URL-Decodes a given string using UTF-8. No UnsupportedEncodingException to handle as it is dealt with in this method.

decodeUrlIso

public static String decodeUrlIso(String stringToDecode)

URL-Decodes a given string using ISO-8859-1. No UnsupportedEncodingException to handle as it is dealt with in this method.

md5

public static String md5(String stringToEncode)

Generates the MD5 digest (32 hex characters) for a given String based on UTF-8.

sha1

public static String sha1(String stringToEncode)

Generates the SHA-1 digest (40 hex characters) for a given String based on UTF-8. The SHA-1 algorithm produces less collisions than MD5.

Returns:

SHA-1 digest

sha256

public static String sha256(String stringToEncode)

Generates the SHA-256 digest (64 hex characters) for a given String based on UTF-8. The SHA-256 algorithm is less broken than SHA-1.

Returns:

SHA-256 digest

digest

public static String digest(String string,
 String digestAlgo,
 String encoding)

Generates a digest (hex string) for the given string

hex

public static String hex(byte[] bytes)

parseHex

public static byte[] parseHex(String hex)

Throws:

IllegalArgumentException - if the given string is invalid hex

parseHexDigit

public static int parseHexDigit(char c)

Throws:

IllegalArgumentException - if the given char is invalid hex

resolveEntity

public static String resolveEntity(String entity)

Simple HTML/XML entity resolving: Only supports unicode entities and a very limited number text represented entities (apos, quot, gt, lt, and amp). There are many more: http://www.w3.org/TR/REC-html40/sgml/dtd.html

Parameters:

entity - The entity name without invalid input: '&' and ; (null throws NPE)

Returns:

Resolved entity or the entity itself if it could not be resolved.

ellipsize

public static String ellipsize(String text,
 int maxLength)

Cuts the string at the end if it's longer than maxLength and appends "..." to it. The length of the resulting string including "..." is always less or equal to the given maxLength. It's valid to pass a null text; in this case null is returned.

ellipsize

public static String ellipsize(String text,
 int maxLength,
 String end)

Cuts the string at the end if it's longer than maxLength and appends the given end string to it. The length of the resulting string is always less or equal to the given maxLength. It's valid to pass a null text; in this case null is returned.

splitLines

public static String[] splitLines(String text,
 boolean skipEmptyLines)

findLinesContaining

public static List<String> findLinesContaining(String text,
 String searchText)

join

public static String join(Iterable<?> iterable,
 String separator)

Joins the given iterable objects using the given separator into a single string.

Returns:

the joined string or an empty string if iterable is null

join

public static String join(int[] array,
 String separator)

Joins the given ints using the given separator into a single string.

Returns:

the joined string or an empty string if the int array is null

join

public static String join(String[] array,
 String separator)

Joins the given Strings using the given separator into a single string.

Returns:

the joined string or an empty string if the String array is null