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ADF Utility : Evaluating EL expressions

To evaluate an EL expression from ADF managed classes, such as managed beans.

  public Object getExpressionValue(String jsfExpression)
  {
    // when specifying EL expression in managed bean as "literal" value
    // so t can be evaluated later, the # is replaced with $, quite strange
    if (jsfExpression == null)
    {
      return jsfExpression;
    }
    if (jsfExpression.startsWith("${"))
    {
      jsfExpression = "#{" + jsfExpression.substring(2);
    }
    if (!jsfExpression.startsWith("#{"))
    {
      if (jsfExpression.equalsIgnoreCase("true"))
      {
        return Boolean.TRUE;
      }
      else if (jsfExpression.equalsIgnoreCase("false"))
      {
        return Boolean.FALSE;
      }
      // there can be literal text preceding the expression...
      else if (jsfExpression.indexOf("#{")<0)
      {
        return jsfExpression;
      }
    }
    ValueExpression ve =  getApplication().getExpressionFactory().createValueExpression(getFacesContext().getELContext(),jsfExpression,Object.class);
    return ve.getValue(getFacesContext().getELContext());
  }

NOTE : This is widely available in ADF community, but I just wanted to make this available for directly for those who are looking for only this.

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