resultiterator.java

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package cn.js.fan.db;

import java.util.*;

/**
 * 用法如下：
 * <tr>
 * <%@ taglib uri="/WEB-INF/tlds/ResultTag.tld" prefix="rm" %>
 * <rm:RITag query="select name, link from nav order by orders" db="redmoon">
 *    <td width=94><img src="images/seperate.gif" width="13" height="26" align="absmiddle">&nbsp;<rm:RRTag field="name"/></td>
 * </rm:RITag>
 * <tr>
 *
 * <p>Title: </p>
 *
 * <p>Description: </p>
 *
 * <p>Copyright: Copyright (c) 2004</p>
 *
 * <p>Company: </p>
 *
 * @author not attributable
 * @version 1.0
 */
public class ResultIterator implements Iterator,java.io.Serializable {
    HashMap mapIndex;
    Vector result;
    int curRowIndex = 0;
    int rows = 0;
    Vector curRow;
    long total = 0;   // 查询所得记录的全部数量,用于分页

    public ResultIterator() {

    }

    public ResultIterator(Vector result, HashMap mapIndex) {
        if (result==null)
            return;
        this.result = result;
        rows = result.size();
        this.mapIndex = mapIndex;
    }

    public ResultIterator(Vector result, HashMap mapIndex, long total) {
        if (result==null)
            return;
        this.result = result;
        this.total = total;
        rows = result.size();
        this.mapIndex = mapIndex;
    }

    /**
     * 查询所得的记录数
     * @return int
     */
    public int size() {
        return rows;
    }

    public int getRows() {
        return rows;
    }

    public void setTotal(long t) {
        this.total = t;
    }

    public long getTotal() {
        return this.total;
    }

    /**
     * Returns <tt>true</tt> if the iteration has more elements.
     *
     * @return <tt>true</tt> if the iterator has more elements.
     * @todo Implement this java.util.Iterator method
     */
    public boolean hasNext() {
        if (result==null) return false;
        if (curRowIndex<=rows-1)
            return true;
        else
            return false;
    }

    /**
     * Returns the next element in the iteration.
     *
     * @return the next element in the iteration.
     * @todo Implement this java.util.Iterator method
     */
    public Object next() {
        curRow = (Vector)result.elementAt(curRowIndex);
        curRowIndex ++;
        return new ResultRecord(curRow, mapIndex);
    }

    /**
     * Removes from the underlying collection the last element returned by
     * the iterator (optional operation).
     *
     * @todo Implement this java.util.Iterator method
     */
    public void remove() throws RuntimeException {
        throw new RuntimeException("This operate is not suported！");
    }

}