[Springframework-cvs] spring/src/org/springframework/web/util WebUtils.java, 1.44, 1.45

[Juergen H. <jho...@us...>]

Update of /cvsroot/springframework/spring/src/org/springframework/web/util
In directory sc8-pr-cvs8.sourceforge.net:/tmp/cvs-serv28952/src/org/springframework/web/util

Modified Files:
	WebUtils.java 
Log Message:
added "findParameterValue" convenience method to WebUtils

Index: WebUtils.java
===================================================================
RCS file: /cvsroot/springframework/spring/src/org/springframework/web/util/WebUtils.java,v
retrieving revision 1.44
retrieving revision 1.45
diff -C2 -d -r1.44 -r1.45
*** WebUtils.java	2 Apr 2008 22:26:05 -0000	1.44
--- WebUtils.java	24 Apr 2008 21:29:48 -0000	1.45
***************
*** 463,466 ****
--- 463,528 ----
  
  	/**
+ 	 * Obtain a named parameter from the given request parameters.
+ 	 * <p>See {@link #findParameterValue(java.util.Map, String)}
+ 	 * for a description of the lookup algorithm.
+ 	 * @param request current HTTP request
+ 	 * @param name the <i>logical</i> name of the request parameter
+ 	 * @return the value of the parameter, or <code>null</code>
+ 	 * if the parameter does not exist in given request
+ 	 */
+ 	public static String findParameterValue(ServletRequest request, String name) {
+ 		return findParameterValue(request.getParameterMap(), name);
+ 	}
+ 
+ 	/**
+ 	 * Obtain a named parameter from the given request parameters.
+ 	 * <p>This method will try to obtain a parameter value using the
+ 	 * following algorithm:
+ 	 * <ol>
+ 	 * <li>Try to get the parameter value using just the given <i>logical</i> name.
+ 	 * This handles parameters of the form <tt>logicalName = value</tt>. For normal
+ 	 * parameters, e.g. submitted using a hidden HTML form field, this will return
+ 	 * the requested value.</li>
+ 	 * <li>Try to obtain the parameter value from the parameter name, where the
+ 	 * parameter name in the request is of the form <tt>logicalName_value = xyz</tt>
+ 	 * with "_" being the configured delimiter. This deals with parameter values
+ 	 * submitted using an HTML form submit button.</li>
+ 	 * <li>If the value obtained in the previous step has a ".x" or ".y" suffix,
+ 	 * remove that. This handles cases where the value was submitted using an
+ 	 * HTML form image button. In this case the parameter in the request would
+ 	 * actually be of the form <tt>logicalName_value.x = 123</tt>. </li>
+ 	 * </ol>
+ 	 * @param parameters the available parameter map
+ 	 * @param name the <i>logical</i> name of the request parameter
+ 	 * @return the value of the parameter, or <code>null</code>
+ 	 * if the parameter does not exist in given request
+ 	 */
+ 	public static String findParameterValue(Map parameters, String name) {
+ 		// First try to get it as a normal name=value parameter
+ 		String value = (String) parameters.get(name);
+ 		if (value != null) {
+ 			return value;
+ 		}
+ 		// If no value yet, try to get it as a name_value=xyz parameter
+ 		String prefix = name + "_";
+ 		Iterator paramNames = parameters.keySet().iterator();
+ 		while (paramNames.hasNext()) {
+ 			String paramName = (String) paramNames.next();
+ 			if (paramName.startsWith(prefix)) {
+ 				// Support images buttons, which would submit parameters as name_value.x=123
+ 				for (int i = 0; i < SUBMIT_IMAGE_SUFFIXES.length; i++) {
+ 					String suffix = SUBMIT_IMAGE_SUFFIXES[i];
+ 					if (paramName.endsWith(suffix)) {
+ 						return paramName.substring(prefix.length(), paramName.length() - suffix.length());
+ 					}
+ 				}
+ 				return paramName.substring(prefix.length());
+ 			}
+ 		}
+ 		// We couldn't find the parameter value...
+ 		return null;
+ 	}
+ 
+ 	/**
  	 * Return a map containing all parameters with the given prefix.
  	 * Maps single values to String and multiple values to String array.