errorstag.java

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package jaction.view.taglib;

import javax.servlet.jsp.*;
import javax.servlet.jsp.tagext.*;
import java.io.*;
import java.lang.StringBuffer;
import java.util.Hashtable;
import java.util.Enumeration;

import jaction.workspace.ActionError;
import jaction.workspace.ActionErrors;
import jaction.workspace.Jaction;
import jaction.utility.FileUtil;

/**
 * 错误处理标记库
 * @author yanger
 * @version $Revision: 1.4.3.0 $ 2003-5-1 1:10
 */

public class ErrorsTag extends BodyTagSupport {


	/**
	 * 错误集合
	 */
	public ActionErrors errors;
	/**
	 * 标签处理开始
	 * @return int 下一步处理标志
	 */
	public int doStartTag() throws JspException {
		StringBuffer buffer = new StringBuffer();
		
		//查找错误集合
		Object obj = pageContext.findAttribute(Jaction.ACTIONERRORS_KEY);
		ActionErrors actionErrors = null;
			if(obj instanceof ActionErrors){
				actionErrors = (ActionErrors)obj;
			}else{
				return SKIP_BODY;
			}
		
		//
		Hashtable errors = actionErrors.toHashtable();
		//循环取得所有错误
		for (Enumeration e = errors.keys() ; e.hasMoreElements() ;) {
			String key = (String)e.nextElement();
			ActionError actionError = (ActionError)errors.get(key);
			buffer.append("<li>"+actionError.getMessage());
		}
		write(buffer.toString());
		
		return SKIP_BODY;
	}
	/**
	 * 标签处理结束
	 * @return int 下一步处理标志
	 */
	public int doEndTag() throws JspException {
		//清除错误信息
		pageContext.removeAttribute(Jaction.ACTIONERRORS_KEY); 
		return EVAL_PAGE;
	}
	/**
	 * 初始化标签
	 */
	public void doInitBody() {
		
	}
	/**
	 * 写html代码
	 * @param html html代码
	 */
	public void write(String html){
		try{
			pageContext.getOut().write(html);
		}catch(IOException ioe){
			ioe.printStackTrace(); 

			FileUtil.log("ActionErrors.write() error"+ioe);

		}
	}

}