nexttag.java

用jbuilder写的源程序

/**
 * Copyright 2003-2006 the original author or authors. Licensed under the Apache
 * License, Version 2.0 (the "License"); you may not use this file except in
 * compliance with the License. You may obtain a copy of the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */

package com.jdon.strutsutil.taglib;

import java.io.IOException;

import javax.servlet.http.HttpServletResponse;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.tagext.BodyTagSupport;

public class NextTag extends BodyTagSupport {

    private boolean disp = false;

    private String name = null;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int doStartTag() throws JspException {

        String dispStrs = (String) pageContext.getAttribute(MPageTag.DISP);
        if ((dispStrs != null) && (!dispStrs.equals(""))) {
            if (dispStrs.equals("on"))
                disp = true;
            else if (dispStrs.equals("off"))
                disp = false;
        }

        String startStrs = (String) pageContext.getAttribute(MPageTag.START);
        int start = Integer.parseInt(startStrs);

        String url = (String) pageContext.getAttribute(MPageTag.URLNAME);

        String countStrs = (String) pageContext.getAttribute(MPageTag.COUNT);
        int count = Integer.parseInt(countStrs);

        String allCountStrs = (String) pageContext.getAttribute(MPageTag.ALLCOUNT);
        int allCount = Integer.parseInt(allCountStrs);
      

        StringBuffer buf = new StringBuffer(100);

        if ((allCount > (start + count)) ) {
            buf.append("<a href=\"");
            buf.append(url);
            buf.append("&start=");
            buf.append((start + count));
            buf.append("\" >");
            if (name != null)
                buf.append(name);
        } else
            buf.append("");

        output(buf.toString());                

        return (EVAL_BODY_INCLUDE);

    }

    /**
     * Render the end of the hyperlink.
     * 
     * @exception JspException
     *                if a JSP exception has occurred
     */
    public int doEndTag() throws JspException {
        output("</a>");
        return (EVAL_PAGE);

    }

    private void output(String s) throws JspException {
        HttpServletResponse response = (HttpServletResponse) pageContext.getResponse();
        JspWriter writer = pageContext.getOut();
        try {
            if (disp)
                writer.print(s);
        } catch (IOException e) {
            throw new JspException("NextTag error");
        }

    }

    
    public void release() {
        super.release();
        disp = false;
        name = null;

    }

  

}