Package net.sf.basedb.core

Class StringUtil

java.lang.Object

net.sf.basedb.core.StringUtil

public class StringUtil
extends Object

Utility methods that will make it easier to implement data validation for string attributes.

Version:

2.0

Author:

Nicklas

Constructor Summary

Constructors

Constructor	Description
StringUtil()

Method Summary

Modifier and Type	Method	Description
static String	coalesce(String... values)	Return the first non-null value (or null if all values are null).
static String	decapitalize(String value)	Decapitalize the string by making sure the first character is lower-case.
static String	getCommonPrefix(Collection<String> strings)	Find the longest common prefix for a collection of strings.
static boolean	isEqualOrNull(String s1, String s2)	Check if two strings are equal or both are null.
static boolean	isEqualOrNull(String s1, String s2, boolean caseInsensitive)	Check if two strings are equal or both are null.
static String	join(Collection<?> values, String deliminator, boolean skipNull)	Join a collection of values to a string, using the specified delimiator.
static String	setNotNullString(String value, String name, int maxLength)	Trim and check the length of a string.
static String	setNullableString(String value, String name, int maxLength)	Trim and check the length of a string.
static String[]	tokenize(String s, String regexp, boolean notInsideQuotes)	Tokenize a string by splitting it at positions matching the regular expression, optionally ignoring matches that are inside quotes.
static String[]	tokenize(String s, String regexp, boolean notInsideQuotes, boolean removeQuotes)	Tokenize a string by splitting it at positions matching the regular expression.
static String	trimString(String s, int length)	Trim a string to a maximum length.
static String	trimStringMiddle(String s, int length)	Trim a string to a maximum length.

Methods inherited from class java.lang.Object

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

Constructor Details

StringUtil

public StringUtil()

Method Details

setNullableString

public static String setNullableString(String value,
String name,
int maxLength)
                                throws StringTooLongException

Trim and check the length of a string. Null values are allowed.

Parameters:

value - The string to check

name - The name of the attribute to use if an exception is thrown

maxLength - The maximum length of the string

Returns:

The original string, trimmed from white-space at the beginning and end

Throws:

StringTooLongException - If the string is too long

setNotNullString

public static String setNotNullString(String value,
String name,
int maxLength)
                               throws InvalidUseOfNullException,
StringTooLongException

Trim and check the length of a string. Null values are not allowed.

Parameters:

value - The string to check

name - The name of the attribute to use if an exception is thrown

maxLength - The maximum length of the string

Returns:

The original string, trimmed from white-space at the beginning and end

Throws:

StringTooLongException - If the string is too long

InvalidUseOfNullException - If the string is null

isEqualOrNull

public static boolean isEqualOrNull(String s1,
String s2)

Check if two strings are equal or both are null.

Parameters:

s1 - The first string

s2 - The second string

Returns:

TRUE if the strings are equal or both are null, FALSE otherwise

isEqualOrNull

public static boolean isEqualOrNull(String s1,
String s2,
boolean caseInsensitive)

Check if two strings are equal or both are null.

Parameters:

s1 - The first string

s2 - The second string

caseInsensitive - TRUE if the comparison should ignore case, FALSE otherwise

Returns:

TRUE if the strings are equal or both are null, FALSE otherwise

Since:

2.4

join

public static final String join(Collection<?> values,
String deliminator,
boolean skipNull)

Join a collection of values to a string, using the specified delimiator.

Parameters:

values - The values to join

deliminator - The deliminator between the values

skipNull - If null values should be skipper or not

Returns:

The resulting string

trimString

public static final String trimString(String s,
int length)

Trim a string to a maximum length. String longer than the specified length will be cut off and three dots are appended. If no trimming is needed the original string is returned.

Parameters:

s - The string to trim

length - The maximum length of the string

Returns:

The trimmed string

trimStringMiddle

public static final String trimStringMiddle(String s,
int length)

Trim a string to a maximum length. Strings longer than the specified length will have text cut-out from the middle and replaced by three dots. If no trimming is needed the original string is returned.

Parameters:

s - The string to trim

length - The maximum length of the string

Returns:

The trimmed string

Since:

2.14

tokenize

public static final String[] tokenize(String s,
String regexp,
boolean notInsideQuotes)

Tokenize a string by splitting it at positions matching the regular expression, optionally ignoring matches that are inside quotes.

Parameters:

s - The string to tokenize

regexp - The regular expression for matching split sites

notInsideQuotes - If TRUE, the regexp is not matched inside quotes

Returns:

An array with the elements of the array

Since:

2.15

tokenize

public static final String[] tokenize(String s,
String regexp,
boolean notInsideQuotes,
boolean removeQuotes)

Tokenize a string by splitting it at positions matching the regular expression. Matches that are inside quotes can optionally be ignored. Elements with quotes can optionally have the quotes removed.

Parameters:

s - The string to tokenize

regexp - The regular expression for matching split sites

notInsideQuotes - If TRUE, the regexp is not matched inside quotes

removeQuotes - If TRUE, remove quotes from all elements before returning the result

Returns:

An array with the elements of the array

Since:

2.17

getCommonPrefix

public static final String getCommonPrefix(Collection<String> strings)

Find the longest common prefix for a collection of strings. If the collection is null, empty or contains at least one null element null is returned. If the given strings doesn't have a common prefix the empty string is returned.

Parameters:

strings - A collection of string objects

Returns:

The longes string such that String.startsWith(String) returns true for all strings in the given collection

Since:

2.17

decapitalize

public static final String decapitalize(String value)

Decapitalize the string by making sure the first character is lower-case. All other characters are left as they are. If the string is empty, the empty string is returned. If the string is null, null is returned.

Since:

3.2

coalesce

public static final String coalesce(String... values)

Return the first non-null value (or null if all values are null).

Since:

3.19