Forgot to send render context, copied below:
Briefly the idea of RenderContext is to send to the object's output method a
"context", specifically a HttpServletRequest:
A dependency upon HttpServletRequest might be an issue for some user's as you will
have to be running ECS someplace that has access to servlets. But this is very common,
it seems to me.
Does it seem likely that users of ECS will not like adding such a dependecy? If so
there are many advantages to sending a rendercontext, namely you can start to add the
ability to have elements "look" differently depending upon the context. Here is an
example from my code that shows elements of a select box depending upon things in the
RenderContext:
public void output(RenderContext context){
//this could be optimized to store the result in the user object until the
//user has updated
XML user = (XML)context.getRequest().getAttribute("user");
String selectedOption = context.getRequest().getParameter(mSelectName);
XML selectBoxElement = (XML)user.getElement(mSelectName);
if(selectBoxElement == null){
selectBoxElement = new XML(mSelectName);
if( mOptions != null && mOptions.length > 0 ){
for (int i = 0; i < mOptions.length; i++) {
String key = mOptions[i][0];
String text = mOptions[i][1];
setUserSelectBoxElements(user, mSelectName, key, text);
}
selectBoxElement = (XML)user.getElement(mSelectName);
}else{
user.addElement(mSelectName,selectBoxElement);
}
}
Thanks,
John Nilson
//////////////////////////////////////////////////////////////////
RenderContext.java looks like this:
package org.apache.ecs;
import java.io.*;
import javax.servlet.http.*;
public class RenderContext {
private ByteArrayOutputStream bytearrayoutputstream;
private BufferedOutputStream bufferedoutputstream;
private HttpServletRequest mRequest = null;
/*package private*/ RenderContext() {
bytearrayoutputstream = new ByteArrayOutputStream();
bufferedoutputstream = new BufferedOutputStream(bytearrayoutputstream);
mRequest = null;
}
public RenderContext(HttpServletRequest req) {
bytearrayoutputstream = new ByteArrayOutputStream();
bufferedoutputstream = new BufferedOutputStream(bytearrayoutputstream);
mRequest = req;
}
public BufferedOutputStream getOutput(){
return bufferedoutputstream;
}
public HttpServletRequest getRequest(){
return mRequest;
}
public String toString(){
String s=null;
try {
bufferedoutputstream.flush();
s = bytearrayoutputstream.toString();
}
catch (Exception ex) {
ex.printStackTrace();
}
return s;
}
public void close(){
try {
bufferedoutputstream.close();
bytearrayoutputstream.close();
}catch (Exception ex) {
}
}
}
