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老外写的 StringTool

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/*
 * StringTool.java
 *
 * Created on 2006年5月8日, 下午7:16
 *
 * To change this template, choose Tools | Template Manager
 * and open the template in the editor.
 */


import java.util.Calendar;
import java.util.Enumeration;
import java.util.NoSuchElementException;

/**
 * The string tokenizer class allows an application to break a
 * string into tokens. The tokenization method is much simpler than
 * the one used by the <code>StreamTokenizer</code> class. The
 * <code>StringTool</code> methods do not distinguish among
 * identifiers, numbers, and quoted strings, nor do they recognize
 * and skip comments.
 * <player>
 * The set of delimiters (the characters that separate tokens) may
 * be specified either at creation time or on a per-token basis.
 * <player>
 * An instance of <code>StringTool</code> behaves in one of two
 * ways, depending on whether it was created with the
 * <code>returnDelims</code> flag having the value <code>true</code>
 * or <code>false</code>:
 * <ul>
 * <li>If the flag is <code>false</code>, delimiter characters serve to
 *     separate tokens. A token is a maximal sequence of consecutive
 *     characters that are not delimiters.
 * <li>If the flag is <code>true</code>, 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.
 * </ul><player>
 * A <tt>StringTool</tt> object internally maintains a current
 * position within the string to be tokenized. Some operations advance this
 * current position past the characters processed.<player>
 * A token is returned by taking a substring of the string that was used to
 * create the <tt>StringTool</tt> object.
 * <player>
 * The following is one example of the use of the tokenizer. The code:
 * <blockquote><pre>
 *     StringTool st = new StringTool("this is a test");
 *     while (st.hasMoreTokens()) {
 *         System.out.println(st.nextToken());
 *     }
 * </pre></blockquote>
 * <player>
 * prints the following output:
 * <blockquote><pre>
 *     this
 *     is
 *     a
 *     test
 * </pre></blockquote>
 *
 * <player>
 * <tt>StringTool</tt> 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 <tt>split</tt>
 * method of <tt>String</tt> or the java.util.regex package instead.
 * <player>
 * The following example illustrates how the <tt>String.split</tt>
 * method can be used to break up a string into its basic tokens:
 * <blockquote><pre>
 *     String[] result = "this is a test".split("\\s");
 *     for (int x=0; x&lt;result.length; x++)
 *         System.out.println(result[x]);
 * </pre></blockquote>
 * <player>
 * prints the following output:
 * <blockquote><pre>
 *     this
 *     is
 *     a
 *     test
 * </pre></blockquote>
 *
 * @author  unascribed
 * @version 1.29, 01/23/03
 * @see     java.io.StreamTokenizer
 * @since   JDK1.0
 */
public class StringTool implements Enumeration {
    private int currentPosition;
    private int newPosition;
    private int maxPosition;
    private String str;
    private String delimiters;
    private boolean retDelims;
    private boolean delimsChanged;
    public static final String[] ms = new String[]{"Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dev"};
   
    /**
     * maxDelimChar stores the value of the delimiter character with the
     * highest value. It is used to optimize the detection of delimiter
     * characters.
     */
    private char maxDelimChar;
   
    /**
     * Set maxDelimChar to the highest char in the delimiter set.
     */
   
    private void setMaxDelimChar() {
        if (delimiters == null) {
            maxDelimChar = 0;
            return;
        }
       
        char m = 0;
        for (int i = 0; i < delimiters.length(); i++) {
            char c = delimiters.charAt(i);
            if (m < c)
                m = c;
        }
        maxDelimChar = m;
    }
   
    /**
     * Constructs a string tokenizer for the specified string. All
     * characters in the <code>delim</code> argument are the delimiters
     * for separating tokens.
     * <player>
     * If the <code>returnDelims</code> flag is <code>true</code>, then
     * the delimiter characters are also returned as tokens. Each
     * delimiter is returned as a string of length one. If the flag is
     * <code>false</code>, the delimiter characters are skipped and only
     * serve as separators between tokens.
     * <player>
     * Note that if <tt>delim</tt> is <tt>null</tt>, this constructor does
     * not throw an exception. However, trying to invoke other methods on the
     * resulting <tt>StringTool</tt> may result in a
     * <tt>NullPointerException</tt>.
     *
     * @param   str            a string to be parsed.
     * @param   delim          the delimiters.
     * @param   returnDelims   flag indicating whether to return the delimiters
     *                         as tokens.
     */
    public StringTool(String str, String delim, boolean returnDelims) {
        currentPosition = 0;
        newPosition = -1;
        delimsChanged = false;
        this.str = str;
        maxPosition = str.length();
        delimiters = delim;
        retDelims = returnDelims;
        setMaxDelimChar();
    }
   
    /**
     * Constructs a string tokenizer for the specified string. The
     * characters in the <code>delim</code> argument are the delimiters
     * for separating tokens. Delimiter characters themselves will not
     * be treated as tokens.
     *
     * @param   str     a string to be parsed.
     * @param   delim   the delimiters.
     */
    public StringTool(String str, String delim) {
        this(str, delim, false);
    }
   
    /**
     * Constructs a string tokenizer for the specified string. The
     * tokenizer uses the default delimiter set, which is
     * <code>"&nbsp;&#92;t&#92;n&#92;r&#92;f"</code>: 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.
     *
     * @param   str   a string to be parsed.
     */
    public StringTool(String str) {
        this(str, " \t\n\r\f", false);
    }
   
    /**
     * Skips delimiters starting from the specified position. If retDelims
     * is false, returns the index of the first non-delimiter character at or
     * after startPos. If retDelims is true, startPos is returned.
     */
    private int skipDelimiters(int startPos) {
        if (delimiters == null)
            throw new NullPointerException();
       
        int position = startPos;
        while (!retDelims && position < maxPosition) {
            char c = str.charAt(position);
            if ((c > maxDelimChar) || (delimiters.indexOf(c) < 0))
                break;
            position++;
        }
        return position;
    }
   
    /**
     * Skips ahead from startPos and returns the index of the next delimiter
     * character encountered, or maxPosition if no such delimiter is found.
     */
    private int scanToken(int startPos) {
        int position = startPos;
        while (position < maxPosition) {
            char c = str.charAt(position);
            if ((c <= maxDelimChar) && (delimiters.indexOf(c) >= 0))
                break;
            position++;
        }
        if (retDelims && (startPos == position)) {
            char c = str.charAt(position);
            if ((c <= maxDelimChar) && (delimiters.indexOf(c) >= 0))
                position++;
        }
        return position;
    }
   
    /**
     * Tests if there are more tokens available from this tokenizer's string.
     * If this method returns <tt>true</tt>, then a subsequent call to
     * <tt>nextToken</tt> with no argument will successfully return a token.
     *
     * @return  <code>true</code> if and only if there is at least one token
     *          in the string after the current position; <code>false</code>
     *          otherwise.
     */
    public boolean hasMoreTokens() {
        /*
         * Temporary store this position and use it in the following
         * nextToken() method only if the delimiters have'nt been changed in
         * that nextToken() invocation.
         */
        newPosition = skipDelimiters(currentPosition);
        return (newPosition < maxPosition);
    }
   
    /**
     * Returns the next token from this string tokenizer.
     *
     * @return     the next token from this string tokenizer.
     * @exception  NoSuchElementException  if there are no more tokens in this
     *               tokenizer's string.
     */
    public String nextToken() {
        /*
         * If next position already computed in hasMoreElements() and
         * delimiters have changed between the computation and this invocation,
         * then use the computed value.
         */
       
        currentPosition = (newPosition >= 0 && !delimsChanged) ?
            newPosition : skipDelimiters(currentPosition);
       
        /* Reset these anyway */
        delimsChanged = false;
        newPosition = -1;
       
        if (currentPosition >= maxPosition)
            throw new NoSuchElementException();
        int start = currentPosition;
        currentPosition = scanToken(currentPosition);
        return str.substring(start, currentPosition);
    }
   
    /**
     * Returns the next token in this string tokenizer's string. First,
     * the set of characters considered to be delimiters by this
     * <tt>StringTool</tt> object is changed to be the characters in
     * the string <tt>delim</tt>. 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.
     *
     * @param      delim   the new delimiters.
     * @return     the next token, after switching to the new delimiter set.
     * @exception  NoSuchElementException  if there are no more tokens in this
     *               tokenizer's string.
     */
    public String nextToken(String delim) {
        delimiters = delim;
       
        /* delimiter string specified, so set the appropriate flag. */
        delimsChanged = true;
       
        setMaxDelimChar();
        return nextToken();
    }
   
    /**
     * Returns the same value as the <code>hasMoreTokens</code>
     * method. It exists so that this class can implement the
     * <code>Enumeration</code> interface.
     *
     * @return  <code>true</code> if there are more tokens;
     *          <code>false</code> otherwise.
     * @see     java.util.Enumeration
     * @see     java.util.StringTool#hasMoreTokens()
     */
    public boolean hasMoreElements() {
        return hasMoreTokens();
    }
   
    /**
     * Returns the same value as the <code>nextToken</code> method,
     * except that its declared return value is <code>Object</code> rather than
     * <code>String</code>. It exists so that this class can implement the
     * <code>Enumeration</code> interface.
     *
     * @return     the next token in the string.
     * @exception  NoSuchElementException  if there are no more tokens in this
     *               tokenizer's string.
     * @see        java.util.Enumeration
     * @see        java.util.StringTool#nextToken()
     */
    public Object nextElement() {
        return nextToken();
    }
   
    /**
     * Calculates the number of times that this tokenizer's
     * <code>nextToken</code> method can be called before it generates an
     * exception. The current position is not advanced.
     *
     * @return  the number of tokens remaining in the string using the current
     *          delimiter set.
     * @see     java.util.StringTool#nextToken()
     */
    public int countTokens() {
        int count = 0;
        int currpos = currentPosition;
        while (currpos < maxPosition) {
            currpos = skipDelimiters(currpos);
            if (currpos >= maxPosition)
                break;
            currpos = scanToken(currpos);
            count++;
        }
        return count;
    }
   
    public static long getData(String s){
        Calendar calendar = Calendar.getInstance();
        StringTool su = new StringTool(s," ");
        su.nextToken();
        String date = su.nextToken();
        String time = su.nextToken();
        StringTool sd = new StringTool(date,"-");
        int i = 0;
        while(sd.hasMoreTokens()){
            String temp = sd.nextToken();
            if(i == 0)
                //day
                calendar.set(Calendar.DAY_OF_MONTH,Integer.parseInt(temp));
            else if( i == 1){
                // month
                int j;
                for(j = 0;j<ms.length;j++){
                    if(temp.equals(ms[j])){
                        calendar.set(Calendar.MONTH,j);
                        break;
                    }
                }
            }else{
                calendar.set(Calendar.YEAR,Integer.parseInt(temp));
            }
            i++;
        }
        i=0;
        StringTool st = new StringTool(time,":");
        while(st.hasMoreTokens()){
            String temp = st.nextToken();
            if(i == 0)
                //hour
                calendar.set(Calendar.HOUR_OF_DAY,Integer.parseInt(temp));
            else if( i == 1){
                //minute
                calendar.set(Calendar.MINUTE,Integer.parseInt(temp));
            }else{
                //second
                calendar.set(Calendar.SECOND,Integer.parseInt(temp));
            }
            i++;
        }
        return calendar.getTime().getTime();
    }
   
}

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