jaggregate
Class Strings

java.lang.Object
  jaggregate.Strings

public class Strings
extends Object

Utility class that offers common operations on strings.

Version:

$Id: Strings.java,v 1.7 2008/10/03 19:01:23 pholser Exp $

Author:

Paul Holser

Field Summary

static UnaryFunctor<String,Integer>

LENGTH A function which gives the length of its argument.

Method Summary

static UnaryFunction<String,Character>	charAt(int index) Answers a function which will give the character value of a string target at the given index.
static UnaryPredicate<String>	endsWith(String suffix) Answers a predicate which will answer true if its argument ends with the given suffix.
static UnaryPredicate<String>	equalsIgnoreCase(String comparand) Answers a predicate which will answer true if its argument is equivalent to the given comparand, disregarding case.
static UnaryPredicate<String>	hasSameContentsAs(CharSequence comparand) Answers a predicate which will answer true if its argument has the same string contents as the given comparand.
static UnaryPredicate<String>	hasSubstring(CharSequence substring) Answers a predicate which will answer true if the given substring occurs anywhere within its argument.
static UnaryFunction<String,Integer>	indexOf(int ch) Answers a function which will give the first index of a given character value in a given string.
static UnaryFunction<String,Integer>	indexOf(String substring) Answers a function which will give the first index of a given substring in a given string.
static UnaryPredicate<String>	isPrefixOf(String target) Answers a predicate which will answer true if its argument is a prefix of the given target.
static UnaryPredicate<CharSequence>	isSubstringOf(String target) Answers a predicate which will answer true if the given string has the predicate's argument as a substring.
static UnaryPredicate<String>	isSuffixOf(String target) Answers a predicate which will answer true if its argument is a suffix of the given string.
static UnaryFunction<String,Integer>	lastIndexOf(int ch) Answers a function which will give the last index of a given character value in a given string.
static UnaryFunction<String,Integer>	lastIndexOf(String substring) Answers a function which will give the last index of a given substring in a given string.
static UnaryPredicate<CharSequence>	matchesPattern(String pattern) Answers a predicate which will answer true if any part of its argument matches the given regular expression pattern.
static UnaryPredicate<String>	patternMatches(CharSequence target) Answers a predicate which will answer true if its regular expression pattern argument matches the given target.
static UnaryPredicate<String>	startsWith(String prefix) Answers a predicate which will answer true if its argument starts with the given prefix.
static UnaryFunction<String,String>	substring(int index) Answers a function which will give the substring of a given string beginning at the given index.

Methods inherited from class java.lang.Object

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

Field Detail

LENGTH

public static final UnaryFunctor<String,Integer> LENGTH

A function which gives the length of its argument.

See Also:

String.length()

Method Detail

hasSubstring

public static UnaryPredicate<String> hasSubstring(CharSequence substring)

Answers a predicate which will answer true if the given substring occurs anywhere within its argument.

Parameters:

substring - the comparand to use with the returned predicate

Returns:

a predicate that can be used to compare arguments with substring

Throws:

NullPointerException - if substring is null

See Also:

String.contains(CharSequence)

isSubstringOf

public static UnaryPredicate<CharSequence> isSubstringOf(String target)

Answers a predicate which will answer true if the given string has the predicate's argument as a substring.

Parameters:

target - the comparand to use with the returned predicate

Returns:

a predicate that can be used to compare arguments with target

Throws:

NullPointerException - if target is null

See Also:

String.contains(CharSequence)

hasSameContentsAs

public static UnaryPredicate<String> hasSameContentsAs(CharSequence comparand)

Answers a predicate which will answer true if its argument has the same string contents as the given comparand.

Parameters:

comparand - the comparand to use with the returned predicate

Returns:

a predicate that can be used to compare arguments with comparand

Throws:

NullPointerException - if comparand is null

See Also:

String.contentEquals(CharSequence)

endsWith

public static UnaryPredicate<String> endsWith(String suffix)

Answers a predicate which will answer true if its argument ends with the given suffix.

Parameters:

suffix - the comparand to use with the returned predicate

Returns:

a predicate that can be used to compare arguments with suffix

Throws:

NullPointerException - if suffix is null

See Also:

String.endsWith(String)

isSuffixOf

public static UnaryPredicate<String> isSuffixOf(String target)

Answers a predicate which will answer true if its argument is a suffix of the given string.

Parameters:

target - the comparand to use with the returned predicate

Returns:

a predicate that can be used to compare arguments with target

Throws:

NullPointerException - if target is null

See Also:

String.endsWith(String)

startsWith

public static UnaryPredicate<String> startsWith(String prefix)

Answers a predicate which will answer true if its argument starts with the given prefix.

Parameters:

prefix - the comparand to use with the returned predicate

Returns:

a predicate that can be used to compare arguments with prefix

Throws:

NullPointerException - if prefix is null

isPrefixOf

public static UnaryPredicate<String> isPrefixOf(String target)

Answers a predicate which will answer true if its argument is a prefix of the given target.

Parameters:

target - the comparand to use with the returned predicate

Returns:

a predicate that can be used to compare arguments with target

Throws:

NullPointerException - if target is null

equalsIgnoreCase

public static UnaryPredicate<String> equalsIgnoreCase(String comparand)

Answers a predicate which will answer true if its argument is equivalent to the given comparand, disregarding case.

Parameters:

comparand - the comparand to use with the returned predicate

Returns:

a predicate that can be used to compare arguments with comparand

Throws:

NullPointerException - if comparand is null

See Also:

String.equalsIgnoreCase(String)

matchesPattern

public static UnaryPredicate<CharSequence> matchesPattern(String pattern)

Answers a predicate which will answer true if any part of its argument matches the given regular expression pattern.

Parameters:

pattern - the comparand to use with the returned predicate

Returns:

a predicate that can be used to compare arguments with pattern

Throws:

NullPointerException - if pattern is null

See Also:

Matcher.find()

patternMatches

public static UnaryPredicate<String> patternMatches(CharSequence target)

Answers a predicate which will answer true if its regular expression pattern argument matches the given target.

Parameters:

target - the comparand to use with the returned predicate

Returns:

a predicate that can be used to compare arguments with target

Throws:

NullPointerException - if target is null

See Also:

Matcher.find()

charAt

public static UnaryFunction<String,Character> charAt(int index)

Answers a function which will give the character value of a string target at the given index.

Parameters:

index - index into a target string

Returns:

a function that will interrogate strings for the character at index

See Also:

String.charAt(int)

indexOf

public static UnaryFunction<String,Integer> indexOf(int ch)

Answers a function which will give the first index of a given character value in a given string.

Parameters:

ch - desired character in the target string

Returns:

a function that will interrogate strings for the first index of ch

See Also:

String.indexOf(int)

indexOf

public static UnaryFunction<String,Integer> indexOf(String substring)

Answers a function which will give the first index of a given substring in a given string.

Parameters:

substring - desired substring in the target string

Returns:

a function that will interrogate strings for the first index of substring

See Also:

String.indexOf(String)

lastIndexOf

public static UnaryFunction<String,Integer> lastIndexOf(int ch)

Answers a function which will give the last index of a given character value in a given string.

Parameters:

ch - desired character in the target string

Returns:

a function that will interrogate strings for the last index of ch

See Also:

String.lastIndexOf(int)

lastIndexOf

public static UnaryFunction<String,Integer> lastIndexOf(String substring)

Answers a function which will give the last index of a given substring in a given string.

Parameters:

substring - desired substring in the target string

Returns:

a function that will interrogate strings for the last index of substring

See Also:

String.lastIndexOf(String)

substring

public static UnaryFunction<String,String> substring(int index)

Answers a function which will give the substring of a given string beginning at the given index.

Parameters:

index - index at which to start the substring

Returns:

a function that will interrogate strings for substrings

See Also:

String.substring(int)