Example of Map of the returned value of request. getParameterMap in java

It is easy to obtain the parameters submitted on the jsp page, but it can be used to convert the parameters and values in the request into a map. The following is a map structure formed by printing the obtained parameters and values: map (key, value []), that is, the key is a String type, and the value is a String type array.
For example:
The form request contains the multi-choice box checkbox or the parameter t1 = 1 & t1 = 2 & t2 = 3 in the request.
Map structure:

The code is as follows:	Copy code
Key = t1; value [0] = 1, value [1] = 2 Key = t2; value [0] = 3

If map. get ("t1 & Prime;), the result will be: Ljava. lang. string; value is only in the array format, which prevents the same parameter name.

Example

The code is as follows:

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/** * Obtain the parameter Map from the request and return a readable Map.  * * @ Param request * @ Return */ @ SuppressWarnings ("unchecked ") Public static Map getParameterMap (HttpServletRequest request ){ // Parameter Map Map properties = request. getParameterMap (); // Return Value Map Map returnMap = new HashMap (); Iterator entries = properties. entrySet (). iterator (); Map. Entry entry; String name = ""; String value = ""; While (entries. hasNext ()){ Entry = (Map. Entry) entries. next (); Name = (String) entry. getKey (); Object valueObj = entry. getValue (); If (null = valueObj ){ Value = ""; } Else if (valueObj instanceof String []) { String [] values = (String []) valueObj; For (int I = 0; I <values. length; I ++ ){ Value = values [I] + ",";    } Value = value. substring (0, value. length ()-1 ); } Else { Value = valueObj. toString ();   } ReturnMap. put (name, value );  } Return returnMap; }