tagbase.java

java+jsp华源网校+西部软件jsp版

package org.jetic.web;

import java.sql.ResultSet;
import java.util.Vector;
import javax.servlet.jsp.*;
import javax.servlet.jsp.tagext.*;
import org.jetic.util.Format;

/**
 * Title:        经天科技
 * Description:
 * Copyright:    Copyright (c) 2001
 * Company:      www.jetic.org 经天
 * @author hover
 * @version 1.0
 */

public class TagBase extends BodyTagSupport {
    protected ResultSet rs;
    private DataBase dbo;
    private TagBase childTag;

    public TagBase() {}

    public void setChildTag(TagBase newChildTag) {
        childTag = newChildTag;
    }

    public void setDbo(DataBase newDbo) {
        dbo = newDbo;
    }

    public int doStartTag() throws javax.servlet.jsp.JspException {
        childTag.init();
        try {
            if (rs.next()) {
                childTag.writeBody();
                return EVAL_BODY_TAG;
            }
            else {
                return SKIP_BODY;
            }
        }
        catch (Exception ex) {
            ex.printStackTrace(System.err);
            return SKIP_BODY;
        }
    }

    public int doAfterBody() throws javax.servlet.jsp.JspException {
        BodyContent body = getBodyContent();
        try {
            if (rs.next()) {
                childTag.writeBody();
                return EVAL_BODY_TAG;
            }
            else {
                childTag.destroy();
                body.writeOut(body.getEnclosingWriter());
                return SKIP_BODY;
            }
        }
        catch (Exception ex) {
            ex.printStackTrace(System.err);
            return SKIP_BODY;
        }
    }

    public void init() {}
    public void destroy() {}

    public void writeBody() {
        try {
            Vector fields = dbo.getFields();
            DataField field;
            int index;
            for (index = 0; index < fields.size(); index++) {
                field = (DataField)(fields.elementAt(index));
                if (field.outable) {
                    if (field.type == DataField.TYPE_INT)
                        pageContext.setAttribute(field.name, new Integer(rs.getInt(index + 1)));
                    else
                        pageContext.setAttribute(field.name,
                            Format.toHtml(rs.getString(index + 1)));
                }
                else {
                    // do nothing
                    if (field.type == DataField.TYPE_INT)
                        rs.getInt(index + 1);
                    else
                        rs.getString(index + 1);
                }
            }
        }
        catch (Exception ex) {
            ex.printStackTrace(System.err);
        }
    }
}