JSF, writeAttribute("value", str, null) fails with strings obtained through ValueExpression.getValue
- by Roma
Hello,
I'm having a somewhat weird problem with custom JSF component.
Here's my renderer code:
public class Test extends Renderer {
public void encodeBegin(final FacesContext context,
final UIComponent component) throws IOException {
ResponseWriter writer = context.getResponseWriter();
writer.startElement("textarea", component);
String clientId = component.getClientId(context);
if (clientId != null)
writer.writeAttribute("name", clientId, null);
ValueExpression exp = component.getValueExpression("value");
if (exp != null && exp.getValue(context.getELContext()) != null) {
String val = (String) exp.getValue(context.getELContext());
System.out.println("Value: " + val);
writer.writeAttribute("value", val, null);
}
writer.endElement("textarea");
writer.flush();
}
}
The code generates:
<textarea name="j_id2:j_id12:j_id19" value=""></textarea>
Property binding contains "test" and as it should be, "Value: test" is successfully printed to console.
Now, if I change the code to:
public void encodeBegin(final FacesContext context,
final UIComponent component) throws IOException {
ResponseWriter writer = context.getResponseWriter();
writer.startElement("textarea", component);
String clientId = component.getClientId(context);
if (clientId != null)
writer.writeAttribute("name", clientId, null);
ValueExpression exp = component.getValueExpression("value");
if (exp != null && exp.getValue(context.getELContext()) != null) {
String val = (String) exp.getValue(context.getELContext());
String str = "new string";
System.out.println("Value1: " + val + ", Value2: " + str);
writer.writeAttribute("value", str, null);
}
writer.endElement("textarea");
writer.flush();
}
generated html is:
<textarea name="j_id2:j_id12:j_id19" value="new string"></textarea>
and console output is "Value1: test, Value2: new string"
What's going on here? This doesn't make sense. Why would writeAttribute differentiate between the two strings?
Additional info:
The component extends UIComponentBase
I am using it with facelets
