org.apache.xml.utils

Interface XMLString

public interface XMLString

This class is meant to be an interface to character strings, whether they be java Strings or org.apache.xml.utils.FastStringBuffers, or other character data. By using XMLString, character copies can be reduced in the XML pipeline.
Method Summary
abstract charcharAt(int index)
Returns the character at the specified index.
abstract intcompareTo(XMLString anotherString)
Compares two strings lexicographically.
abstract intcompareToIgnoreCase(XMLString str)
Compares two strings lexicographically, ignoring case considerations.
abstract XMLStringconcat(String str)
Concatenates the specified string to the end of this string.
abstract voiddispatchAsComment(LexicalHandler lh)
Directly call the comment method on the passed LexicalHandler for the string-value.
abstract voiddispatchCharactersEvents(ContentHandler ch)
Directly call the characters method on the passed ContentHandler for the string-value.
abstract booleanendsWith(String suffix)
Tests if this string ends with the specified suffix.
abstract booleanequals(XMLString anObject)
Compares this string to the specified object.
abstract booleanequals(Object anObject)
Compares this string to the specified object.
abstract booleanequalsIgnoreCase(String anotherString)
Compares this String to another String, ignoring case considerations.
XMLStringfixWhiteSpace(boolean trimHead, boolean trimTail, boolean doublePunctuationSpaces)
Conditionally trim all leading and trailing whitespace in the specified String.
abstract voidgetChars(int srcBegin, int srcEnd, char[] dst, int dstBegin)
Copies characters from this string into the destination character array.
abstract inthashCode()
Returns a hashcode for this string.
abstract booleanhasString()
Tell if this object contains a java String object.
abstract intindexOf(int ch)
Returns the index within this string of the first occurrence of the specified character.
abstract intindexOf(int ch, int fromIndex)
Returns the index within this string of the first occurrence of the specified character, starting the search at the specified index.
abstract intindexOf(String str)
Returns the index within this string of the first occurrence of the specified substring.
abstract intindexOf(XMLString str)
Returns the index within this string of the first occurrence of the specified substring.
abstract intindexOf(String str, int fromIndex)
Returns the index within this string of the first occurrence of the specified substring, starting at the specified index.
abstract intlastIndexOf(int ch)
Returns the index within this string of the last occurrence of the specified character.
abstract intlastIndexOf(int ch, int fromIndex)
Returns the index within this string of the last occurrence of the specified character, searching backward starting at the specified index.
abstract intlastIndexOf(String str)
Returns the index within this string of the rightmost occurrence of the specified substring.
abstract intlastIndexOf(String str, int fromIndex)
Returns the index within this string of the last occurrence of the specified substring.
abstract intlength()
Returns the length of this string.
abstract booleanstartsWith(String prefix, int toffset)
Tests if this string starts with the specified prefix beginning a specified index.
abstract booleanstartsWith(XMLString prefix, int toffset)
Tests if this string starts with the specified prefix beginning a specified index.
abstract booleanstartsWith(String prefix)
Tests if this string starts with the specified prefix.
abstract booleanstartsWith(XMLString prefix)
Tests if this string starts with the specified prefix.
abstract XMLStringsubstring(int beginIndex)
Returns a new string that is a substring of this string.
abstract XMLStringsubstring(int beginIndex, int endIndex)
Returns a new string that is a substring of this string.
doubletoDouble()
Convert a string to a double -- Allowed input is in fixed notation ddd.fff.
abstract XMLStringtoLowerCase(Locale locale)
Converts all of the characters in this String to lower case using the rules of the given Locale.
abstract XMLStringtoLowerCase()
Converts all of the characters in this String to lower case using the rules of the default locale, which is returned by Locale.getDefault.
abstract StringtoString()
This object (which is already a string!)
abstract XMLStringtoUpperCase(Locale locale)
Converts all of the characters in this String to upper case using the rules of the given locale.
abstract XMLStringtoUpperCase()
Converts all of the characters in this String to upper case using the rules of the default locale, which is returned by Locale.getDefault.
abstract XMLStringtrim()
Removes white space from both ends of this string.

Method Detail

charAt

public abstract char charAt(int index)
Returns the character at the specified index. An index ranges from 0 to length() - 1. The first character of the sequence is at index 0, the next at index 1, and so on, as for array indexing.

Parameters: index the index of the character.

Returns: the character at the specified index of this string. The first character is at index 0.

Throws: IndexOutOfBoundsException if the index argument is negative or not less than the length of this string.

compareTo

public abstract int compareTo(XMLString anotherString)
Compares two strings lexicographically.

Parameters: anotherString the String to be compared.

Returns: the value 0 if the argument string is equal to this string; a value less than 0 if this string is lexicographically less than the string argument; and a value greater than 0 if this string is lexicographically greater than the string argument.

Throws: java.lang.NullPointerException if anotherString is null.

compareToIgnoreCase

public abstract int compareToIgnoreCase(XMLString str)
Compares two strings lexicographically, ignoring case considerations. This method returns an integer whose sign is that of this.toUpperCase().toLowerCase().compareTo( str.toUpperCase().toLowerCase()).

Note that this method does not take locale into account, and will result in an unsatisfactory ordering for certain locales. The java.text package provides collators to allow locale-sensitive ordering.

Parameters: str the String to be compared.

Returns: a negative integer, zero, or a positive integer as the the specified String is greater than, equal to, or less than this String, ignoring case considerations.

Since: 1.2

See Also: java.text.Collator#compare(String, String)

concat

public abstract XMLString concat(String str)
Concatenates the specified string to the end of this string.

Parameters: str the String that is concatenated to the end of this String.

Returns: a string that represents the concatenation of this object's characters followed by the string argument's characters.

Throws: java.lang.NullPointerException if str is null.

dispatchAsComment

public abstract void dispatchAsComment(LexicalHandler lh)
Directly call the comment method on the passed LexicalHandler for the string-value.

Parameters: lh A non-null reference to a LexicalHandler.

Throws: org.xml.sax.SAXException

dispatchCharactersEvents

public abstract void dispatchCharactersEvents(ContentHandler ch)
Directly call the characters method on the passed ContentHandler for the string-value. Multiple calls to the ContentHandler's characters methods may well occur for a single call to this method.

Parameters: ch A non-null reference to a ContentHandler.

Throws: org.xml.sax.SAXException

endsWith

public abstract boolean endsWith(String suffix)
Tests if this string ends with the specified suffix.

Parameters: suffix the suffix.

Returns: true if the character sequence represented by the argument is a suffix of the character sequence represented by this object; false otherwise. Note that the result will be true if the argument is the empty string or is equal to this String object as determined by the equals method.

Throws: java.lang.NullPointerException if suffix is null.

equals

public abstract boolean equals(XMLString anObject)
Compares this string to the specified object. The result is true if and only if the argument is not null and is a String object that represents the same sequence of characters as this object.

Parameters: anObject the object to compare this String against.

Returns: true if the String are equal; false otherwise.

See Also: java.lang.String#compareTo(java.lang.String) java.lang.String#equalsIgnoreCase(java.lang.String)

equals

public abstract boolean equals(Object anObject)
Compares this string to the specified object. The result is true if and only if the argument is not null and is a String object that represents the same sequence of characters as this object.

Parameters: anObject the object to compare this String against.

Returns: true if the String are equal; false otherwise.

See Also: java.lang.String#compareTo(java.lang.String) java.lang.String#equalsIgnoreCase(java.lang.String)

equalsIgnoreCase

public abstract boolean equalsIgnoreCase(String anotherString)
Compares this String to another String, ignoring case considerations. Two strings are considered equal ignoring case if they are of the same length, and corresponding characters in the two strings are equal ignoring case.

Parameters: anotherString the String to compare this String against.

Returns: true if the argument is not null and the Strings are equal, ignoring case; false otherwise.

See Also: equals java.lang.Character#toLowerCase(char) java.lang.Character#toUpperCase(char)

fixWhiteSpace

public XMLString fixWhiteSpace(boolean trimHead, boolean trimTail, boolean doublePunctuationSpaces)
Conditionally trim all leading and trailing whitespace in the specified String. All strings of white space are replaced by a single space character (#x20), except spaces after punctuation which receive double spaces if doublePunctuationSpaces is true. This function may be useful to a formatter, but to get first class results, the formatter should probably do it's own white space handling based on the semantics of the formatting object.

Parameters: trimHead Trim leading whitespace? trimTail Trim trailing whitespace? doublePunctuationSpaces Use double spaces for punctuation?

Returns: The trimmed string.

getChars

public abstract void getChars(int srcBegin, int srcEnd, char[] dst, int dstBegin)
Copies characters from this string into the destination character array.

Parameters: srcBegin index of the first character in the string to copy. srcEnd index after the last character in the string to copy. dst the destination array. dstBegin the start offset in the destination array.

Throws: IndexOutOfBoundsException If any of the following is true:

NullPointerException if dst is null

hashCode

public abstract int hashCode()
Returns a hashcode for this string. The hashcode for a String object is computed as
 s[0]*31^(n-1) + s[1]*31^(n-2) + ... + s[n-1]
 
using int arithmetic, where s[i] is the ith character of the string, n is the length of the string, and ^ indicates exponentiation. (The hash value of the empty string is zero.)

Returns: a hash code value for this object.

hasString

public abstract boolean hasString()
Tell if this object contains a java String object.

Returns: true if this XMLString can return a string without creating one.

indexOf

public abstract int indexOf(int ch)
Returns the index within this string of the first occurrence of the specified character. If a character with value ch occurs in the character sequence represented by this String object, then the index of the first such occurrence is returned -- that is, the smallest value k such that:
 this.charAt(k) == ch
 
is true. If no such character occurs in this string, then -1 is returned.

Parameters: ch a character.

Returns: the index of the first occurrence of the character in the character sequence represented by this object, or -1 if the character does not occur.

indexOf

public abstract int indexOf(int ch, int fromIndex)
Returns the index within this string of the first occurrence of the specified character, starting the search at the specified index.

If a character with value ch occurs in the character sequence represented by this String object at an index no smaller than fromIndex, then the index of the first such occurrence is returned--that is, the smallest value k such that:

 (this.charAt(k) == ch) && (k >= fromIndex)
 
is true. If no such character occurs in this string at or after position fromIndex, then -1 is returned.

There is no restriction on the value of fromIndex. If it is negative, it has the same effect as if it were zero: this entire string may be searched. If it is greater than the length of this string, it has the same effect as if it were equal to the length of this string: -1 is returned.

Parameters: ch a character. fromIndex the index to start the search from.

Returns: the index of the first occurrence of the character in the character sequence represented by this object that is greater than or equal to fromIndex, or -1 if the character does not occur.

indexOf

public abstract int indexOf(String str)
Returns the index within this string of the first occurrence of the specified substring. The integer returned is the smallest value k such that:
 this.startsWith(str, k)
 
is true.

Parameters: str any string.

Returns: if the string argument occurs as a substring within this object, then the index of the first character of the first such substring is returned; if it does not occur as a substring, -1 is returned.

Throws: java.lang.NullPointerException if str is null.

indexOf

public abstract int indexOf(XMLString str)
Returns the index within this string of the first occurrence of the specified substring. The integer returned is the smallest value k such that:
 this.startsWith(str, k)
 
is true.

Parameters: str any string.

Returns: if the string argument occurs as a substring within this object, then the index of the first character of the first such substring is returned; if it does not occur as a substring, -1 is returned.

Throws: java.lang.NullPointerException if str is null.

indexOf

public abstract int indexOf(String str, int fromIndex)
Returns the index within this string of the first occurrence of the specified substring, starting at the specified index. The integer returned is the smallest value k such that:
 this.startsWith(str, k) && (k >= fromIndex)
 
is true.

There is no restriction on the value of fromIndex. If it is negative, it has the same effect as if it were zero: this entire string may be searched. If it is greater than the length of this string, it has the same effect as if it were equal to the length of this string: -1 is returned.

Parameters: str the substring to search for. fromIndex the index to start the search from.

Returns: If the string argument occurs as a substring within this object at a starting index no smaller than fromIndex, then the index of the first character of the first such substring is returned. If it does not occur as a substring starting at fromIndex or beyond, -1 is returned.

Throws: java.lang.NullPointerException if str is null

lastIndexOf

public abstract int lastIndexOf(int ch)
Returns the index within this string of the last occurrence of the specified character. That is, the index returned is the largest value k such that:
 this.charAt(k) == ch
 
is true. The String is searched backwards starting at the last character.

Parameters: ch a character.

Returns: the index of the last occurrence of the character in the character sequence represented by this object, or -1 if the character does not occur.

lastIndexOf

public abstract int lastIndexOf(int ch, int fromIndex)
Returns the index within this string of the last occurrence of the specified character, searching backward starting at the specified index. That is, the index returned is the largest value k such that:
 this.charAt(k) == ch) && (k <= fromIndex)
 
is true.

Parameters: ch a character. fromIndex the index to start the search from. There is no restriction on the value of fromIndex. If it is greater than or equal to the length of this string, it has the same effect as if it were equal to one less than the length of this string: this entire string may be searched. If it is negative, it has the same effect as if it were -1: -1 is returned.

Returns: the index of the last occurrence of the character in the character sequence represented by this object that is less than or equal to fromIndex, or -1 if the character does not occur before that point.

lastIndexOf

public abstract int lastIndexOf(String str)
Returns the index within this string of the rightmost occurrence of the specified substring. The rightmost empty string "" is considered to occur at the index value this.length(). The returned index is the largest value k such that
 this.startsWith(str, k)
 
is true.

Parameters: str the substring to search for.

Returns: if the string argument occurs one or more times as a substring within this object, then the index of the first character of the last such substring is returned. If it does not occur as a substring, -1 is returned.

Throws: java.lang.NullPointerException if str is null.

lastIndexOf

public abstract int lastIndexOf(String str, int fromIndex)
Returns the index within this string of the last occurrence of the specified substring.

Parameters: str the substring to search for. fromIndex the index to start the search from. There is no restriction on the value of fromIndex. If it is greater than the length of this string, it has the same effect as if it were equal to the length of this string: this entire string may be searched. If it is negative, it has the same effect as if it were -1: -1 is returned.

Returns: If the string argument occurs one or more times as a substring within this object at a starting index no greater than fromIndex, then the index of the first character of the last such substring is returned. If it does not occur as a substring starting at fromIndex or earlier, -1 is returned.

Throws: java.lang.NullPointerException if str is null.

length

public abstract int length()
Returns the length of this string.

Returns: the length of the sequence of characters represented by this object.

startsWith

public abstract boolean startsWith(String prefix, int toffset)
Tests if this string starts with the specified prefix beginning a specified index.

Parameters: prefix the prefix. toffset where to begin looking in the string.

Returns: true if the character sequence represented by the argument is a prefix of the substring of this object starting at index toffset; false otherwise. The result is false if toffset is negative or greater than the length of this String object; otherwise the result is the same as the result of the expression

          this.subString(toffset).startsWith(prefix)
          

Throws: java.lang.NullPointerException if prefix is null.

startsWith

public abstract boolean startsWith(XMLString prefix, int toffset)
Tests if this string starts with the specified prefix beginning a specified index.

Parameters: prefix the prefix. toffset where to begin looking in the string.

Returns: true if the character sequence represented by the argument is a prefix of the substring of this object starting at index toffset; false otherwise. The result is false if toffset is negative or greater than the length of this String object; otherwise the result is the same as the result of the expression

          this.subString(toffset).startsWith(prefix)
          

Throws: java.lang.NullPointerException if prefix is null.

startsWith

public abstract boolean startsWith(String prefix)
Tests if this string starts with the specified prefix.

Parameters: prefix the prefix.

Returns: true if the character sequence represented by the argument is a prefix of the character sequence represented by this string; false otherwise. Note also that true will be returned if the argument is an empty string or is equal to this String object as determined by the equals method.

Throws: java.lang.NullPointerException if prefix is null.

Since: JDK1. 0

startsWith

public abstract boolean startsWith(XMLString prefix)
Tests if this string starts with the specified prefix.

Parameters: prefix the prefix.

Returns: true if the character sequence represented by the argument is a prefix of the character sequence represented by this string; false otherwise. Note also that true will be returned if the argument is an empty string or is equal to this String object as determined by the equals method.

Throws: java.lang.NullPointerException if prefix is null.

Since: JDK1. 0

substring

public abstract XMLString substring(int beginIndex)
Returns a new string that is a substring of this string. The substring begins with the character at the specified index and extends to the end of this string.

Examples:

 "unhappy".substring(2) returns "happy"
 "Harbison".substring(3) returns "bison"
 "emptiness".substring(9) returns "" (an empty string)
 

Parameters: beginIndex the beginning index, inclusive.

Returns: the specified substring.

Throws: IndexOutOfBoundsException if beginIndex is negative or larger than the length of this String object.

substring

public abstract XMLString substring(int beginIndex, int endIndex)
Returns a new string that is a substring of this string. The substring begins at the specified beginIndex and extends to the character at index endIndex - 1. Thus the length of the substring is endIndex-beginIndex.

Parameters: beginIndex the beginning index, inclusive. endIndex the ending index, exclusive.

Returns: the specified substring.

Throws: IndexOutOfBoundsException if the beginIndex is negative, or endIndex is larger than the length of this String object, or beginIndex is larger than endIndex.

toDouble

public double toDouble()
Convert a string to a double -- Allowed input is in fixed notation ddd.fff.

Returns: A double value representation of the string, or return Double.NaN if the string can not be converted.

toLowerCase

public abstract XMLString toLowerCase(Locale locale)
Converts all of the characters in this String to lower case using the rules of the given Locale.

Parameters: locale use the case transformation rules for this locale

Returns: the String, converted to lowercase.

See Also: java.lang.Character#toLowerCase(char) java.lang.String#toUpperCase(Locale)

toLowerCase

public abstract XMLString toLowerCase()
Converts all of the characters in this String to lower case using the rules of the default locale, which is returned by Locale.getDefault.

Returns: the string, converted to lowercase.

See Also: java.lang.Character#toLowerCase(char) java.lang.String#toLowerCase(Locale)

toString

public abstract String toString()
This object (which is already a string!) is itself returned.

Returns: the string itself.

toUpperCase

public abstract XMLString toUpperCase(Locale locale)
Converts all of the characters in this String to upper case using the rules of the given locale.

Parameters: locale use the case transformation rules for this locale

Returns: the String, converted to uppercase.

See Also: java.lang.Character#toUpperCase(char) java.lang.String#toLowerCase(Locale)

toUpperCase

public abstract XMLString toUpperCase()
Converts all of the characters in this String to upper case using the rules of the default locale, which is returned by Locale.getDefault.

If no character in this string has a different uppercase version, based on calling the toUpperCase method defined by Character, then the original string is returned.

Otherwise, this method creates a new String object representing a character sequence identical in length to the character sequence represented by this String object and with every character equal to the result of applying the method Character.toUpperCase to the corresponding character of this String object.

Examples:

 "Fahrvergnügen".toUpperCase() returns "FAHRVERGNÜGEN"
 "Visit Ljubinje!".toUpperCase() returns "VISIT LJUBINJE!"
 

Returns: the string, converted to uppercase.

See Also: java.lang.Character#toUpperCase(char) java.lang.String#toUpperCase(Locale)

trim

public abstract XMLString trim()
Removes white space from both ends of this string.

If this String object represents an empty character sequence, or the first and last characters of character sequence represented by this String object both have codes greater than '\u0020' (the space character), then a reference to this String object is returned.

Otherwise, if there is no character with a code greater than '\u0020' in the string, then a new String object representing an empty string is created and returned.

Otherwise, let k be the index of the first character in the string whose code is greater than '\u0020', and let m be the index of the last character in the string whose code is greater than '\u0020'. A new String object is created, representing the substring of this string that begins with the character at index k and ends with the character at index m-that is, the result of this.substring(km+1).

This method may be used to trim Character#isSpace(char) whitespace from the beginning and end of a string; in fact, it trims all ASCII control characters as well.

Returns: this string, with white space removed from the front and end.

Copyright B) 2005 Apache XML Project. All Rights Reserved.