Enumeration<Object>
public class StringTokenizer extends Object implements Enumeration<Object>
StreamTokenizer
class. The StringTokenizer
methods do not distinguish among identifiers, numbers, and quoted strings, nor do they recognize and skip comments. The set of delimiters (the characters that separate tokens) may be specified either at creation time or on a per-token basis.
An instance of StringTokenizer
behaves in one of two ways, depending on whether it was created with the returnDelims
flag having the value true
or false
:
false
, delimiter characters serve to separate tokens. A token is a maximal sequence of consecutive characters that are not delimiters. true
, delimiter characters are themselves considered to be tokens. A token is thus either one delimiter character, or a maximal sequence of consecutive characters 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 characters processed.
A token is returned by taking a substring of the string that was used to create the StringTokenizer
object.
The following is one example of the use of the tokenizer. The code:
StringTokenizer st = new StringTokenizer("this is a test"); while (st.hasMoreTokens()) { System.out.println(st.nextToken()); }
prints the following output:
this is a test
StringTokenizer
is a legacy class that is retained for compatibility reasons although its use is discouraged in new code. It is recommended that anyone seeking this functionality use the split
method of String
or the java.util.regex package instead.
The following example illustrates how the String.split
method can be used to break up a string into its basic tokens:
String[] result = "this is a test".split("\\s"); for (int x=0; x<result.length; x++) System.out.println(result[x]);
prints the following output:
this is a test
Constructor | Description |
---|---|
StringTokenizer |
Constructs a string tokenizer for the specified string. |
StringTokenizer |
Constructs a string tokenizer for the specified string. |
StringTokenizer |
Constructs a string tokenizer for the specified string. |
Modifier and Type | Method | Description |
---|---|---|
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 |
Returns the next token in this string tokenizer's string. |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
asIterator
public StringTokenizer(String str, String delim, boolean returnDelims)
delim
argument are the delimiters for separating tokens. If the returnDelims
flag is true
, then the delimiter characters are also returned as tokens. Each delimiter is returned as a string consisting of a single Unicode code point of the delimiter (which may be one or two char
s). If the flag is false
, the delimiter characters are skipped and only serve as separators between tokens.
Note that if delim
is null
, this constructor does not throw an exception. However, trying to invoke other methods on the resulting StringTokenizer
may result in a NullPointerException
.
str
- a string to be parsed.delim
- the delimiters.returnDelims
- flag indicating whether to return the delimiters as tokens.NullPointerException
- if str is null
public StringTokenizer(String str, String delim)
delim
argument are the delimiters for separating tokens. Delimiter characters themselves will not be treated as tokens. Note that if delim
is null
, this constructor does not throw an exception. However, trying to invoke other methods on the resulting StringTokenizer
may result in a NullPointerException
.
str
- a string to be parsed.delim
- the delimiters.NullPointerException
- if str is null
public StringTokenizer(String str)
" \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.str
- a string to be parsed.NullPointerException
- if str is null
public boolean hasMoreTokens()
true
, then a subsequent call to nextToken
with no argument will successfully return a token.true
if and only if there is at least one token in the string after the current position; false
otherwise.public String nextToken()
NoSuchElementException
- if there are no more tokens in this tokenizer's string.public String nextToken(String delim)
StringTokenizer
object is changed to be the characters in the string delim
. Then the next token in the string after the current position is returned. The current position is advanced beyond the recognized token. The new delimiter set remains the default after this call.delim
- the new delimiters.NoSuchElementException
- if there are no more tokens in this tokenizer's string.NullPointerException
- if delim is null
public boolean hasMoreElements()
hasMoreTokens
method. It exists so that this class can implement the Enumeration
interface.hasMoreElements
in interface Enumeration<Object>
true
if there are more tokens; false
otherwise.public Object nextElement()
nextToken
method, except that its declared return value is Object
rather than String
. It exists so that this class can implement the Enumeration
interface.nextElement
in interface Enumeration<Object>
NoSuchElementException
- if there are no more tokens in this tokenizer's string.public int countTokens()
nextToken
method can be called before it generates an exception. The current position is not advanced.
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Documentation extracted from Debian's OpenJDK Development Kit package.
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https://docs.oracle.com/en/java/javase/21/docs/api/java.base/java/util/StringTokenizer.html