Java Code Examples for javax.el.ValueExpression#getExpressionString()

/**
 * Return the core value expression of a specified component
 * 
 * @param component
 * @return
 */
public static String getCoreValueExpression(UIComponent component) {
	ValueExpression valueExpression = component.getValueExpression("value");
	if (null != valueExpression) {
		String v = valueExpression.getExpressionString();
		if (null != v) {
			Matcher matcher = EL_EXPRESSION.matcher(v);
			if (matcher.find()) {
				String exp = matcher.group();
				return exp.substring(2, exp.length() - 1);
			}
			return v;
		}
	}
	return null;
}
 

public String resolveStaticField(ValueExpression expression) {
	if (expression != null) {
		String expressionString = expression.getExpressionString();
		expressionString = expressionString.substring(2, expressionString.length() - 1); // Remove #{}
		return expressionString.substring(expressionString.indexOf(".") + 1); // Remove var
	} else {
		return null;
	}
}
 

/**
 * Which annotations are given to an object displayed by a JSF component?
 *
 * @param p_component
 *            the component
 * @return null if there are no annotations, or if they cannot be accessed
 */
public static Annotation[] readAnnotations(UIComponent p_component) {
	ValueExpression valueExpression = p_component.getValueExpression("value");
	if (valueExpression != null && valueExpression.getExpressionString() != null && valueExpression.getExpressionString().length()>0) {
		return readAnnotations(valueExpression, p_component);
	}
	return null;
}
 

private static Object evaluteBaseForMojarra(ELContext elContext, ValueExpression p_expression) {
	String exp = p_expression.getExpressionString();
	int endOfBaseName = exp.lastIndexOf('.');
	int mapDelimiterPos = exp.lastIndexOf('[');
	if (mapDelimiterPos >= 0) {
		int mapEndDelimiterPos = exp.lastIndexOf(']');
		if (endOfBaseName < mapEndDelimiterPos) {
			endOfBaseName = mapDelimiterPos; // treat the [...] as field
		}
	}

	if (endOfBaseName < 0) {
		LOGGER.log(Level.WARNING, "There's no getter to access: #{" + p_expression + "}");
		return null;
	}
	String basename = exp.substring(2, endOfBaseName);

	Object result = evalAsObject("#{" + basename + "}");
	if (null != result) {
		return result;
	}

	int start = 0;
	int end = basename.indexOf('.', start);
	int end2 = basename.indexOf('[', start);
	if (end2 >= 0 && end2 < end) {
		end = end2;
	}
	if (end < 0) {
		end = basename.length();
	}
	String variableName = basename.substring(start, end);
	FaceletContext faceletContext = (FaceletContext) FacesContext.getCurrentInstance().getAttributes()
			.get(FaceletContext.FACELET_CONTEXT_KEY);
	Object resolvedBase = faceletContext.getAttribute(variableName);
	if (resolvedBase != null) {
		if (endOfBaseName == end + 2) {
			result = resolvedBase;
		} else {
			basename = basename.substring(end + 1, endOfBaseName - 2);
			result = elContext.getELResolver().getValue(elContext, resolvedBase, basename);
		}
	}

	return result;
}
 

/**
 * This methods generates the HTML code of the current b:radiobutton.
* <code>encodeBegin</code> generates the start of the component. After the, the JSF framework calls <code>encodeChildren()</code>
* to generate the HTML code between the beginning and the end of the component. For instance, in the case of a panel component
* the content of the panel is generated by <code>encodeChildren()</code>. After that, <code>encodeEnd()</code> is called
* to generate the rest of the HTML code.
 * @param context the FacesContext.
 * @param component the current b:radiobutton.
 * @throws IOException thrown if something goes wrong when writing the HTML code.
 */
@Override
public void encodeBegin(FacesContext context, UIComponent component) throws IOException {
    if (!component.isRendered()) {
        return;
    }
	Radiobutton radiobutton = (Radiobutton) component;
	ResponseWriter rw = context.getResponseWriter();
	String clientId = radiobutton.getClientId();

	ValueExpression valueExpression = radiobutton.getValueExpression("value");
	if (null == valueExpression) {
		throw new FacesException("Radiobuttons always need a value. More precisely, the value attribute must be an EL expression pointing to an attribute of a JSF bean.");
	}
	String propertyName = valueExpression.getExpressionString();
	Object beanValue = ELTools.evalAsObject(propertyName);
	if (propertyName.startsWith("#{") && propertyName.endsWith("}")) {
		propertyName=propertyName.substring(2, propertyName.length()-1).trim();
	} else {
		throw new FacesException("The value attribute of a radiobutton must be an EL expression.");
	}
	UIForm form = findSurroundingForm(component);
	if (null == form) {
		throw new FacesException("Radio buttons must be inside a form.");
	}
	
	String name = radiobutton.getName();
	if (null == name) {
		throw new FacesException("Please specify the 'name' attribute of the radio button.");
	}
	UIComponent radioButtonGroup = findComponentByName(form, name);
	String radiobuttonGroupId = radioButtonGroup.getClientId(context);

	RadioButtonInternalStateBean state = (RadioButtonInternalStateBean) ELTools.evalAsObject("#{radioButtonInternalStateBean}");
	
	String key = "BF_generated_radiobuttonfield_"+radiobuttonGroupId;
	if (!state.inputHasAlreadyBeenRendered(key)) {
		rw.startElement("input", null);
		rw.writeAttribute("id", "input_" + clientId, null);
		rw.writeAttribute("name", name, null);
		rw.writeAttribute("type",  "hidden", null);
		rw.writeAttribute("value", String.valueOf(beanValue), null);
		AJAXRenderer.generateBootsFacesAJAXAndJavaScript(FacesContext.getCurrentInstance(), radiobutton, rw, false);

		rw.endElement("input");

	}

	Converter converter = radiobutton.getConverter();
	List<SelectItemAndComponent> options = SelectItemUtils.collectOptions(context, component, converter);
	if (options.size()>0) {
		// traditional JSF approach using f:selectItem[s]
		int counter=0;
		for (SelectItemAndComponent option:options) {
			generateASingleRadioButton(context, component, radiobutton, rw, propertyName, beanValue,
					option.getSelectItem().getValue(),
					option.getSelectItem().getLabel(), clientId+(counter++), option.getSelectItem().isDisabled());

		}

	} else {
		// BootsFaces approach using b:radioButtons for each radiobutton item
		String itemValue = radiobutton.getItemValue();
		String itemLabel = radiobutton.getItemLabel();
		if (itemLabel == null) {
			itemLabel = radiobutton.getItemValue();
		}
		String itemId = clientId;

		generateASingleRadioButton(context, component, radiobutton, rw, propertyName, beanValue, itemValue,
				itemLabel, itemId, false);
	}
}