com.ibm.icu.util
public final class StringTokenizer extends Object implements Enumeration
The string tokenizer class allows an application to break a string
into tokens by performing code point comparison.
The StringTokenizer
methods do not distinguish
among identifiers, numbers, and quoted strings, nor do they recognize
and skip comments.
The set of delimiters (the codepoints that separate tokens) may be specified either at creation time or on a per-token basis.
An instance of StringTokenizer
behaves in one of three ways,
depending on whether it was created with the returnDelims
and coalesceDelims
flags having the value true
or false
:
false
, delimiter code points serve to
separate tokens. A token is a maximal sequence of consecutive
code points that are not delimiters.
true
, delimiter code points are
themselves considered to be tokens. In this case, if coalesceDelims is
true
, such tokens will be the maximal sequence of consecutive
code points that are delimiters. If coalesceDelims is false,
a token will be received for each delimiter code point.
A token is thus either one delimiter code point, a maximal sequence of consecutive code points that are delimiters, or a maximal sequence of consecutive code points that are not delimiters.
A StringTokenizer object internally maintains a current position within the string to be tokenized. Some operations advance this current position past the code point processed.
A token is returned by taking a substring of the string that was used to create the StringTokenizer object.
Example of the use of the default delimiter tokenizer.
StringTokenizer st = new StringTokenizer("this is a test"); while (st.hasMoreTokens()) { println(st.nextToken()); }
prints the following output:
this is a test
Example of the use of the tokenizer with user specified delimiter.
StringTokenizer st = new StringTokenizer( "this is a test with supplementary characters \ud800\ud800\udc00\udc00", " \ud800\udc00"); while (st.hasMoreTokens()) { println(st.nextToken()); }
prints the following output:
this is a test with supplementary characters \ud800 \udc00
UNKNOWN: ICU 2.4
Constructor Summary | |
---|---|
StringTokenizer(String str, UnicodeSet delim, boolean returndelims) Constructs a string tokenizer for the specified string. | |
StringTokenizer(String str, UnicodeSet delim, boolean returndelims, boolean coalescedelims) Constructs a string tokenizer for the specified string. | |
StringTokenizer(String str, UnicodeSet delim) Constructs a string tokenizer for the specified string. | |
StringTokenizer(String str, String delim, boolean returndelims) Constructs a string tokenizer for the specified string. | |
StringTokenizer(String str, String delim, boolean returndelims, boolean coalescedelims) Constructs a string tokenizer for the specified string. | |
StringTokenizer(String str, String delim) Constructs a string tokenizer for the specified string. | |
StringTokenizer(String str) Constructs a string tokenizer for the specified string. |
Method Summary | |
---|---|
int | countTokens()
Calculates the number of times that this tokenizer's
nextToken method can be called before it generates an
exception. |
boolean | hasMoreElements()
Returns the same value as the hasMoreTokens method.
|
boolean | hasMoreTokens()
Tests if there are more tokens available from this tokenizer's
string.
|
Object | nextElement()
Returns the same value as the nextToken method, except
that its declared return value is Object rather than
String . |
String | nextToken()
Returns the next token from this string tokenizer. |
String | nextToken(String delim)
Returns the next token in this string tokenizer's string. |
String | nextToken(UnicodeSet delim)
Returns the next token in this string tokenizer's string. |
Constructs a string tokenizer for the specified string. All characters in the delim argument are the delimiters for separating tokens.
If the returnDelims flag is false, the delimiter characters are skipped and only serve as separators between tokens.
If the returnDelims flag is true, then the delimiter characters are also returned as tokens, one per delimiter.
Parameters: str a string to be parsed. delim the delimiters. returndelims flag indicating whether to return the delimiters as tokens.
Throws: throws a NullPointerException if str is null
UNKNOWN: ICU 2.4
Deprecated: This API is ICU internal only.
Constructs a string tokenizer for the specified string. All characters in the delim argument are the delimiters for separating tokens.
If the returnDelims flag is false, the delimiter characters are skipped and only serve as separators between tokens.
If the returnDelims flag is true, then the delimiter characters are also returned as tokens. If coalescedelims is true, one token is returned for each run of delimiter characters, otherwise one token is returned per delimiter. Since surrogate pairs can be delimiters, the returned token might be two chars in length.
Parameters: str a string to be parsed. delim the delimiters. returndelims flag indicating whether to return the delimiters as tokens. coalescedelims flag indicating whether to return a run of delimiters as a single token or as one token per delimiter. This only takes effect if returndelims is true.
Throws: throws a NullPointerException if str is null
UNKNOWN: ICU 3.4.3
Constructs a string tokenizer for the specified string. The characters in the delim argument are the delimiters for separating tokens.
Delimiter characters themselves will not be treated as tokens.
Parameters: str a string to be parsed. delim the delimiters.
Throws: throws a NullPointerException if str is null
UNKNOWN: ICU 2.4
Constructs a string tokenizer for the specified string. All characters in the delim argument are the delimiters for separating tokens.
If the returnDelims flag is false, the delimiter characters are skipped and only serve as separators between tokens.
If the returnDelims flag is true, then the delimiter characters are also returned as tokens, one per delimiter.
Parameters: str a string to be parsed. delim the delimiters. returndelims flag indicating whether to return the delimiters as tokens.
Throws: throws a NullPointerException if str is null
UNKNOWN: ICU 2.4
Deprecated: This API is ICU internal only.
Constructs a string tokenizer for the specified string. All characters in the delim argument are the delimiters for separating tokens.
If the returnDelims flag is false, the delimiter characters are skipped and only serve as separators between tokens.
If the returnDelims flag is true, then the delimiter characters are also returned as tokens. If coalescedelims is true, one token is returned for each run of delimiter characters, otherwise one token is returned per delimiter. Since surrogate pairs can be delimiters, the returned token might be two chars in length.
Parameters: str a string to be parsed. delim the delimiters. returndelims flag indicating whether to return the delimiters as tokens. coalescedelims flag indicating whether to return a run of delimiters as a single token or as one token per delimiter. This only takes effect if returndelims is true.
Throws: throws a NullPointerException if str is null
UNKNOWN: ICU 3.4.3
Constructs a string tokenizer for the specified string. The characters in the delim argument are the delimiters for separating tokens.
Delimiter characters themselves will not be treated as tokens.
Parameters: str a string to be parsed. delim the delimiters.
Throws: throws a NullPointerException if str is null
UNKNOWN: ICU 2.4
Constructs a string tokenizer for the specified string. The tokenizer uses the default delimiter set, which is " \t\n\r\f": the space character, the tab character, the newline character, the carriage-return character, and the form-feed character.
Delimiter characters themselves will not be treated as tokens.
Parameters: str a string to be parsed
Throws: throws a NullPointerException if str is null
UNKNOWN: ICU 2.4
nextToken
method can be called before it generates an
exception. The current position is not advanced.Returns: the number of tokens remaining in the string using the current delimiter set.
See Also: nextToken
UNKNOWN: ICU 2.4
hasMoreTokens
method.
It exists so that this class can implement the
Enumeration
interface.Returns: true
if there are more tokens;
false
otherwise.
See Also: hasMoreTokens
UNKNOWN: ICU 2.4
Returns: true
if and only if there is at least one token
in the string after the current position; false
otherwise.
UNKNOWN: ICU 2.4
nextToken
method, except
that its declared return value is Object
rather than
String
. It exists so that this class can implement the
Enumeration
interface.Returns: the next token in the string.
Throws: NoSuchElementException if there are no more tokens in this tokenizer's string.
See Also: nextToken
UNKNOWN: ICU 2.4
Returns: the next token from this string tokenizer.
Throws: NoSuchElementException if there are no more tokens in this tokenizer's string.
UNKNOWN: ICU 2.4
Parameters: delim the new delimiters.
Returns: the next token, after switching to the new delimiter set.
Throws: NoSuchElementException if there are no more tokens in this tokenizer's string.
UNKNOWN: ICU 2.4
Parameters: delim the new delimiters.
Returns: the next token, after switching to the new delimiter set.
Throws: NoSuchElementException if there are no more tokens in this tokenizer's string.
UNKNOWN: ICU 2.4