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<title>The Java Language Specification The Package java.util</title>
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<center><h1>21.10 The Class <code>java.util.StringTokenizer</code></h1></center>
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The <code>StringTokenizer</code> class provides a way to break a <code>String</code> into tokens. The
tokenizing method used by this class is much simpler than the one used by the
class <code>java.io.StreamTokenizer</code>. For example, a <code>StringTokenizer</code> does not
distinguish among identifiers, numbers, and quoted strings; moreover, it does not
recognize and skip comments.
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A <code>StringTokenizer</code> can serve as an <code>Enumeration</code> <a href="javautil.doc.html#23147">(§21.1)</a>.<p>
<pre><a name="7649"></a>public class <code><b>StringTokenizer</b></code> implements Enumeration {
<a name="7650"></a> public <code><b>StringTokenizer</b></code>(String str, String delim,
<a name="22141"></a> boolean returnTokens);
<a name="7651"></a> public <code><b>StringTokenizer</b></code>(String str, String delim);
<a name="7652"></a> public <code><b>StringTokenizer</b></code>(String str);
<a name="7653"></a> public boolean <code><b>hasMoreTokens</b></code>();
<a name="7654"></a> public String <code><b>nextToken</b></code>();
<a name="7655"></a> public String <code><b>nextToken</b></code>(String delim);
<a name="7656"></a> public boolean <code><b>hasMoreElements</b></code>();
<a name="7657"></a> public Object <code><b>nextElement</b></code>();
<a name="7658"></a> public int <code><b>countTokens</b></code>();
<a name="7659"></a>}
</pre><a name="22157"></a>
A <code>StringTokenizer</code> simply divides characters into classes: delimiters and other characters. The tokenizer behaves in one of two ways, depending on whether it was created with <code>returnTokens</code> having the value <code>true</code> or <code>false</code>.<p>
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If <code>returnTokens</code> is <code>false</code>, delimiter characters merely serve to separate tokens of interest. A token is thus a maximal sequence of consecutive characters that are not delimiters.<p>
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If <code>returnTokens</code> is <code>true</code>, delimiter characters are themselves considered to be tokens of interest. A token is thus either one delimiter character or a maximal sequence of consecutive characters that are not delimiters.<p>
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A <code>StringTokenizer</code> internally maintains a current position within the <code>String</code> to be tokenized. Some operations advance this current position past the characters processed.<p>
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A token is returned by taking a substring <a href="javalang.doc11.html#14007">(§20.12.32)</a> of the string that was used to create the <code>StringTokenizer</code>.<p>
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<p><font size=+1><strong>21.10.1 </strong> <code>public <code><b>StringTokenizer</b></code>(String str, String delim,<br>      boolean returnTokens)</code></font>
<p>
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This constructor initializes a newly created <code>StringTokenizer</code> so that it will recognize
tokens within the given string <code>str</code>. All characters in the string <code>delim</code> will
be considered delimiters. The argument <code>returnTokens</code> specifies whether delimiter
characters themselves are to be considered tokens.
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<p><font size=+1><strong>21.10.2 </strong> <code>public <code><b>StringTokenizer</b></code>(String str, String delim)</code></font>
<p>
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This constructor initializes a newly created <code>StringTokenizer</code> so that it will recognize
tokens within the given string <code>str</code>. All characters in the string <code>delim</code> will
be considered delimiters. Delimiter characters themselves will not be treated as
tokens.
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<p><font size=+1><strong>21.10.3 </strong> <code>public <code><b>StringTokenizer</b></code>(String str)</code></font>
<p>
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This constructor initializes a newly created <code>StringTokenizer</code> so that it will recognize
tokens within the given string <code>str</code>. All whitespace characters <a href="javalang.doc10.html#36320">(§20.5.19)</a>
will be considered delimiters. Delimiter characters themselves will not be treated
as tokens.
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<p><font size=+1><strong>21.10.4 </strong> <code>public boolean <code><b>hasMoreTokens</b></code>()</code></font>
<p>
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The result is <code>true</code> if and only if there is at least one token in the string after the
current position. If this method returns <code>true</code>, then a subsequent call to <code>nextToken</code>
with no argument will successfully return a token.
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<p><font size=+1><strong>21.10.5 </strong> <code>public String <code><b>nextToken</b></code>()</code></font>
<p>
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The next token in the string after the current position is returned. The current position
is advanced beyond the recognized token.
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<p><font size=+1><strong>21.10.6 </strong> <code>public String <code><b>nextToken</b></code>(String delim)</code></font>
<p>
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First, the set of characters considered to be delimiters by this <code>StringTokenizer</code>
is changed to be the characters in the string <code>delim</code>. Then the next token in the
string after the current position is returned. The current position is advanced
beyond the recognized token.
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<p><font size=+1><strong>21.10.7 </strong> <code>public boolean <code><b>hasMoreElements</b></code>()</code></font>
<p>
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This method has exactly the same behavior as <code>hasMoreTokens</code> <a href="javautil.doc8.html#7663">(§21.10.4)</a>. It is
provided so that a <code>StringTokenizer</code> can serve as an <code>Enumeration</code> <a href="javautil.doc.html#23147">(§21.1)</a>.
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<p><font size=+1><strong>21.10.8 </strong> <code>public Object <code><b>nextElement</b></code>()</code></font>
<p>
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This method has exactly the same behavior as <code>nextToken</code> <a href="javautil.doc8.html#7664">(§21.10.5)</a>. It is provided
so that a <code>StringTokenizer</code> can serve as an <code>Enumeration</code> <a href="javautil.doc.html#23147">(§21.1)</a>.
<p><a name="7668"></a>
<p><font size=+1><strong>21.10.9 </strong> <code>public int <code><b>countTokens</b></code>()</code></font>
<p>
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The result is the number of tokens in the string after the current position, using the
current set of delimiter characters. The current position is not advanced.
<p>
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<font size=-1>Java Language Specification (HTML generated by Suzette Pelouch on February 24, 1998)<br>
<i><a href="jcopyright.doc.html">Copyright © 1996 Sun Microsystems, Inc.</a>
All rights reserved</i>
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Please send any comments or corrections to <a href="mailto:doug.kramer@sun.com">doug.kramer@sun.com</a>
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