jsvaluechangelistenertag.java

一个使用struts+hibernate+spring开发的完的网站源代码。

/*
 * Copyright (c) 2004 Your Corporation. All Rights Reserved.
 */
package org.apache.myfaces.custom.jslistener;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.myfaces.component.html.util.AddResource;
import org.apache.myfaces.custom.jsvalueset.HtmlJsValueSet;
import org.apache.myfaces.taglib.UIComponentTagBase;

import javax.faces.application.Application;
import javax.faces.component.UIComponent;
import javax.faces.component.UINamingContainer;
import javax.faces.context.FacesContext;
import javax.faces.el.ValueBinding;
import javax.faces.webapp.UIComponentTag;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.tagext.Tag;
import javax.servlet.jsp.tagext.TagSupport;

/**
 * @author Martin Marinschek (latest modification by $Author: matzew $)
 * @version $Revision: 1.5 $ $Date: 2005/02/18 17:19:30 $
 * $Log: JsValueChangeListenerTag.java,v $
 * Revision 1.5  2005/02/18 17:19:30  matzew
 * added release() to tag clazzes.
 *
 * Revision 1.4  2005/01/04 16:09:57  mmarinschek
 * ChangeListener now uses renderer
 *
 * Revision 1.3  2004/12/20 06:33:51  mmarinschek
 * bugs killed
 *
 * Revision 1.2  2004/12/19 00:50:55  mmarinschek
 * JsValueSetTag
 *
 * Revision 1.1  2004/12/17 13:19:10  mmarinschek
 * new component jsValueChangeListener
 *
 *
 */
public class JsValueChangeListenerTag
        extends UIComponentTagBase
{

    public String getComponentType()
    {
        return JsValueChangeListener.COMPONENT_TYPE;
    }

    public String getRendererType()
    {
        return "org.apache.myfaces.JsValueChangeListener";
    }

    private String _for;
    private String _property;
    private String _expressionValue;
    
    public void release() {
        super.release();
        _for=null;
        _property=null;
        _expressionValue=null;
    }

    protected void setProperties(UIComponent component)
    {
        super.setProperties(component);

        setStringProperty(component, "for", _for);
        setStringProperty(component, "property", _property);
        setStringProperty(component, "expressionValue", _expressionValue);
    }

    public void setExpressionValue(String expressionValue)
    {
        _expressionValue = expressionValue;
    }

    public void setFor(String aFor)
    {
        _for = aFor;
    }

    public void setProperty(String property)
    {
        _property = property;
    }

    /*

    //private static final Log log = LogFactory.getLog(UpdateActionListenerTag.class);

    private String _for;
    private String _property;
    private String _expressionValue;
    private static Log log = LogFactory.getLog(JsValueChangeListenerTag.class);

    public JsValueChangeListenerTag()
    {
    }

    public void setFor(String aFor)
    {
        _for = aFor;
    }

    public void setExpressionValue(String expressionValue)
    {
        _expressionValue = expressionValue;
    }

    public void setProperty(String property)
    {
        _property = property;
    }


    public int doStartTag() throws JspException
    {
        try
        {
            if (_for == null) throw new JspException("for attribute not set");
            if (_expressionValue == null) throw new JspException("expressionValue attribute not set");

            //Find parent UIComponentTag
            UIComponentTag componentTag = UIComponentTag.getParentUIComponentTag(pageContext);
            if (componentTag == null)
            {
                throw new JspException("ValueChangeListenerTag has no UIComponentTag ancestor");
            }

            if (componentTag.getCreated())
            {
                String aFor = getValueOrBinding(_for);
                String expressionValue = getValueOrBinding(_expressionValue);
                String property = getValueOrBinding(_property);

                AddResource.addJavaScriptToHeader(
                        JsValueChangeListenerTag.class, "JSListener.js", false, getFacesContext());

                //Component was just created, so we add the Listener
                UIComponent component = componentTag.getComponentInstance();

                if(aFor!=null)
                {
                    UIComponent forComponent = component.findComponent(aFor);

                    String forComponentId = null;

                    if (forComponent == null)
                    {
                        if (log.isInfoEnabled())
                        {
                            log.info("Unable to find component '" + aFor + "' (calling findComponent on component '" + component.getClientId(getFacesContext()) + "') - will try to render component id based on the parent-id (on same level)");
                        }
                        if (aFor.length() > 0 && aFor.charAt(0) == UINamingContainer.SEPARATOR_CHAR)
                        {
                            //absolute id path
                            forComponentId = aFor.substring(1);
                        }
                        else
                        {
                            //relative id path, we assume a component on the same level as the label component
                            String labelClientId = component.getClientId(getFacesContext());
                            int colon = labelClientId.lastIndexOf(UINamingContainer.SEPARATOR_CHAR);
                            if (colon == -1)
                            {
                                forComponentId = aFor;
                            }
                            else
                            {
                                forComponentId = labelClientId.substring(0, colon + 1) + aFor;
                            }
                        }
                    }
                    else
                    {
                        forComponentId = forComponent.getClientId(getFacesContext());
                    }

                    expressionValue = expressionValue.replaceAll("\\'","\\\\'");
                    expressionValue = expressionValue.replaceAll("\"","\\\"");


                    String methodCall = "orgApacheMyfacesJsListenerSetExpressionProperty('"+
                            component.getClientId(getFacesContext())+"','"+
                            forComponentId+"',"+
                            (property==null?"null":"'"+property+"'")+
                            ",'"+expressionValue+"');";


                    callMethod(component, "onchange",methodCall);

                }
            }

            return Tag.SKIP_BODY;
        }
        catch(JspException ex)
        {
            log.error("Exception : ",ex);
            throw ex;
        }
    }

    private String getValueOrBinding(String valueOrBinding)
    {
        if(valueOrBinding == null)
            return null;

        String value = valueOrBinding;

        if (UIComponentTag.isValueReference(valueOrBinding))
        {
            ValueBinding binding = getApplication().createValueBinding(valueOrBinding);
            Object val = binding.getValue(getFacesContext());
            value = (val==null?"":val.toString());
        }

        return value;
    }

    private void callMethod(UIComponent uiComponent, String propName, String value)
    {
        Object oldValue = uiComponent.getAttributes().get(propName);

        if(oldValue != null)
        {
            String oldValueStr = oldValue.toString().trim();

            //check if method call has already been added...
            if(oldValueStr.indexOf(value)!=-1)
                return;

            if(oldValueStr.length()>0 && !oldValueStr.endsWith(";"))
                oldValueStr +=";";

            value = oldValueStr + value;

        }

        uiComponent.getAttributes().put(propName, value);
    }

    protected Application getApplication()
    {
        return getFacesContext().getApplication();
    }

    protected FacesContext getFacesContext()
    {
        return FacesContext.getCurrentInstance();
    }           */
}