api/src/main/java/javax/faces/component/UIGraphic.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package javax.faces.component;

import javax.el.ValueExpression;
import javax.faces.context.FacesContext;

import org.apache.myfaces.buildtools.maven2.plugin.builder.annotation.JSFComponent;
import org.apache.myfaces.buildtools.maven2.plugin.builder.annotation.JSFProperty;

/**
 * Displays a graphical image.
 * <p>
 * See the javadoc for this class in the
 * <a href="http://java.sun.com/j2ee/javaserverfaces/1.2/docs/api/index.html">JSF Specification</a>
 * for further details.
 */
@JSFComponent(defaultRendererType = "javax.faces.Image")
public class UIGraphic extends UIComponentBase
{
    public static final String COMPONENT_TYPE = "javax.faces.Graphic";
    public static final String COMPONENT_FAMILY = "javax.faces.Graphic";

    private static final String URL_PROPERTY = "url";
    private static final String VALUE_PROPERTY = "value";

    private Object _value;

    /**
     * Construct an instance of the UIGraphic.
     */
    public UIGraphic()
    {
        setRendererType("javax.faces.Image");
    }

    @Override
    public String getFamily()
    {
        return COMPONENT_FAMILY;
    }

    /**
     * An alias for the "value" attribute.
     */
    @JSFProperty
    public String getUrl()
    {
        return (String) getValue();
    }

    public void setUrl(String url)
    {
        setValue(url);
    }

    @Override
    public ValueExpression getValueExpression(String name)
    {
        if (URL_PROPERTY.equals(name))
        {
            return super.getValueExpression(VALUE_PROPERTY);
        }
        else
        {
            return super.getValueExpression(name);
        }
    }

    @Override
    public void setValueExpression(String name, ValueExpression binding)
    {
        if (URL_PROPERTY.equals(name))
        {
            super.setValueExpression(VALUE_PROPERTY, binding);
        }
        else
        {
            super.setValueExpression(name, binding);
        }
    }

    /**
     * The URL of the image.
     * <p>
     * If the URL starts with a '/', it is relative to the context path of the web application.
     * </p>
     */
    @JSFProperty
    public Object getValue()
    {
        if (_value != null)
        {
            return _value;
        }
        ValueExpression expression = getValueExpression("value");
        if (expression != null)
        {
            return expression.getValue(getFacesContext().getELContext());
        }
        return null;
    }

    public void setValue(Object value)
    {
        this._value = value;
    }

    @Override
    public Object saveState(FacesContext facesContext)
    {
        Object[] values = new Object[2];
        values[0] = super.saveState(facesContext);
        values[1] = _value;

        return values;
    }

    @Override
    public void restoreState(FacesContext facesContext, Object state)
    {
        Object[] values = (Object[]) state;
        super.restoreState(facesContext, values[0]);
        _value = values[1];
    }
}