Once you start using EL heavily within your UI, eventually you will want to use it/evaluate it back in your EJB’s and Seam/Spring components
There are three steps to evaluating an EL expression.
1 2 3 4 5 6 7 8 9 10 11 | //get current EL context javax.el.ELContext elContext = javax.faces.context.FacesContext.getCurrentInstance().getELContext(); //get the expression factory (for seam). You can probably do ExpressionFactory.newInstance() if not using seam . javax.el.ExpressionFactory expressionFactory = org.jboss.seam.core.Expressions.instance().getExpressionFactory(); //Create value expression as the EL I'm evaluating is a value e.g. #{bean.property} . Create MethodExpression if the EL is a method e.g. #{bean.method()} javax.el.ValueExpression valueExpression = expressionFactory.createValueExpression(elContext, elExpressionYouAreEvaluating, WhateverYouAreExpecting.class); // get value and dont' forget to cast. whateverYouAreExpecting = (WhateverYouAreExpecting) valueExpression.getValue(elContext); |
Yup.. that’s how convulted this is . It should more be like below
1 2 | //NOTE: imaginary code Object value = ExpressionFactory.getValue("#{bean.property}"); |
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