src/org/apache/taglibs/rdc/core/StrutsErrorsTag.java

/*
 *    
 *   Copyright 2004 The Apache Software Foundation.
 *
 *  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.
 *
 *
 */
//$Id$
package org.apache.taglibs.rdc.core;

import java.io.IOException;
import java.util.Iterator;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspTagException;
import javax.servlet.jsp.tagext.SimpleTagSupport;

import org.apache.struts.Globals;
import org.apache.struts.action.ActionErrors;
import org.apache.struts.action.ActionMessage;
import org.apache.struts.action.ActionMessages;

/**
 * <p>Tag implementation of the &lt;rdc:struts-errors&gt; tag.
 * Play out any errors messages from the preceding struts action.
 * This basic implementation reports all errors at once and disregards
 * any values specified via the message.</p>
 *  
 * @author Rahul Akolkar
 */

public class StrutsErrorsTag
    extends SimpleTagSupport {

	/*
	 * Constructor
	 */    
    public StrutsErrorsTag() {
    	super();
    }

	/**
 	 * Play out any errors messages from the preceding struts action.
 	 * This basic implementation reports all errors at once and disregards
 	 * any values specified via the message.
 	 * 
	 */
    public void doTag()
        throws IOException, JspException, JspTagException   {

        JspWriter out = getJspContext().getOut();
        Object errors = getJspContext().findAttribute(Globals.ERROR_KEY);
		if (errors == null) {
			return;
		} else if (errors instanceof ActionErrors) {
			// deprecated in Struts 1.2
			out.print("<block>");
			ActionErrors actionErrors = (ActionErrors) errors;
			if (!actionErrors.isEmpty()) {
				Iterator iter = actionErrors.get();
				while (iter.hasNext()) {
					ActionMessage msg = (ActionMessage)iter.next();
					if (msg != null) {
						out.print("<prompt>" + msg.getKey() + "</prompt>");
					}
				}
			}
			out.print("</block>");			
		} else if (errors instanceof ActionMessages) {
			out.print("<block>");
			ActionMessages actionMsgs = (ActionMessages) errors;
			if (!actionMsgs.isEmpty()) {
				Iterator iter = actionMsgs.get();
				while (iter.hasNext()) {
					ActionMessage msg = (ActionMessage)iter.next();
					if (msg != null) {
						out.print("<prompt>" + msg.getKey() + "</prompt>");
					}
				}
			}
			out.print("</block>");			
		} else if (errors instanceof String[]) {
			out.print("<block>");
			String[] errorsArr = (String []) errors;
			for (int i = 0; i < errorsArr.length; i++) {
				if (errorsArr[i] != null) {
					out.print("<prompt>" + errorsArr[i] + "</prompt>");
				}
			}
			out.print("</block>");
		} else if (errors instanceof String && errors != null) {
			out.print("<block><prompt>" + errors + "</prompt></block>");
		}

    }
    
}