writetag.java

一个实用工具类

/*
 * Copyright (C) butor.com. All rights reserved.
 *
 * This software is published under the terms of the GNU Library General
 * Public License (GNU LGPL), a copy of which has been included with this
 * distribution in the LICENSE.txt file. 
 */


package org.butor.web.taglib.bean;

import java.text.ParseException;
import java.util.Date;

import javax.servlet.jsp.JspException;

import org.apache.struts.util.RequestUtils;
import org.apache.struts.util.ResponseUtils;
import org.butor.helper.DateManip;
import org.butor.web.taglib.html.TagLibHelper;

/** 
 * @author nacroaz
 *
 * To change this generated comment edit the template variable "typecomment":
 * Window>Preferences>Java>Templates.
 */
public class WriteTag extends org.apache.struts.taglib.bean.WriteTag {
	protected static final String POSTAL_CODE_FORMAT = "postal";
	protected static final String PHONE_NUMBER_FORMAT = "phone";
	
	protected String keep_format = null;
	public String getKeep_format() {
		return keep_format;
	}
	
	public void setKeep_format(String c) {
		keep_format = c;	
	}
	
	protected Object convertValue(Object value) {
		Object convertedValue = null;

		if (value instanceof String) {
			try {
				// Try double conversion
				Double doubleValue = Double.valueOf((String) value);
				convertedValue = doubleValue;
			} catch (NumberFormatException e) {
				convertedValue = null;
			}

			if (convertedValue == null) {
				// Try date conversion
				try {
					Date dateValue = DateManip.parseDate((String) value);
					convertedValue = dateValue;
				} catch (ParseException e) {
					convertedValue = null;	
				}
			}						
		}
		
		// Keep original value if conversion failed
		if (convertedValue == null) {
			convertedValue = value;
		}
		
		return convertedValue;	
	}


    /**
     * Process the start tag.
     *
     * @exception JspException if a JSP exception has occurred
     */
    public int doStartTag() throws JspException {

        // Look up the requested bean (if necessary)
        //Object bean = null;
        if (ignore) {
            if (RequestUtils.lookup(pageContext, name, scope) == null) {
                return (SKIP_BODY);  // Nothing to output
            }
        }

        // Look up the requested property value
        Object value =
            RequestUtils.lookup(pageContext, name, property, scope);
        if (value == null) {
            return (SKIP_BODY);  // Nothing to output
        }
            
		// Try to retrieve format string from resources by the key from formatKey. To convertValue to a double or date only
		// if their is a format, do we want to format ==> must be a number or a date.
        if( ( getFormat() != null ) || ( getFormatKey()!=null ) ) {
        	if (POSTAL_CODE_FORMAT.equals(getFormat())) {
        		value = TagLibHelper.formatPostalCode(value.toString());
        	} else if (PHONE_NUMBER_FORMAT.equals(getFormat())) {
        		value = TagLibHelper.formatPhoneNumber(value.toString());
        	} else {
				value = convertValue(value);
        	}
        }

        // Convert value to the String with some formatting
        String output = formatValue( value );
        
        boolean mustFormat = (keep_format == null) ? true :  keep_format.equals("1");

        // Print this property value to our output writer, suitably filtered
        if (filter) {
            //ResponseUtils.write(pageContext, ResponseUtils.filter(output));
            output = ResponseUtils.filter(output);
    	}
        //else
            //ResponseUtils.write(pageContext, output);

		TagLibHelper.renderText(pageContext, output, false, mustFormat);
		
        // Continue processing this page
        return (SKIP_BODY);
    }
}