ResetValuesHandler.java

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package com.sun.faces.facelets.tag.jsf.core;


import javax.faces.component.ActionSource;
import javax.faces.component.UIComponent;
import javax.faces.context.FacesContext;
import javax.faces.event.AbortProcessingException;
import javax.faces.event.ActionEvent;
import javax.faces.event.ActionListener;
import javax.faces.view.ActionSource2AttachedObjectHandler;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.List;
import java.util.regex.Pattern;
import javax.faces.component.UIViewRoot;
import javax.faces.view.facelets.FaceletContext;
import javax.faces.view.facelets.TagAttribute;
import javax.faces.view.facelets.TagConfig;

public final class ResetValuesHandler extends ActionListenerHandlerBase
      implements ActionSource2AttachedObjectHandler {
    
    private final TagAttribute render;

    // Pattern used for execute/render string splitting
    private static Pattern SPLIT_PATTERN = Pattern.compile(" ");
    
    
    private final static class LazyActionListener
          implements ActionListener, Serializable {
        Collection<String> render;

        private static final long serialVersionUID = -5676209243297546166L;

        public LazyActionListener(Collection<String> render) {
            this.render = new ArrayList<>(render);
        }

        @Override
        public void processAction(ActionEvent event)
              throws AbortProcessingException {
            FacesContext context = FacesContext.getCurrentInstance();
            UIViewRoot root = context.getViewRoot();
            root.resetValues(context, render);
        }
    }

    /**
     * @param config
     */
    public ResetValuesHandler(TagConfig config) {
        super(config);
        this.render = this.getAttribute("render");
    }


    @Override
    public void applyAttachedObject(FacesContext context, UIComponent parent) {
        FaceletContext ctx = (FaceletContext) context.getAttributes()
              .get(FaceletContext.FACELET_CONTEXT_KEY);
        ActionSource as = (ActionSource) parent;
        String renderStr = (String) render.getObject(ctx, String.class);
        ActionListener listener = new LazyActionListener(toList(renderStr));
        as.addActionListener(listener);
    }
    
    // Converts the specified object to a List<String>
    private static List<String> toList(String strValue) {

        
        // If the value contains no spaces, we can optimize.
        // This is worthwhile, since the execute/render lists
        // will often only contain a single value.
        if (strValue.indexOf(' ') == -1) {
            return Collections.singletonList(strValue);
        }
        
        // We're stuck splitting up the string.
        String[] values = SPLIT_PATTERN.split(strValue);
        if ((values == null) || (values.length == 0)) {
            return null;
        }
        
        // Note that we could create a Set out of the values if
        // we care about removing duplicates.  However, the
        // presence of duplicates does not real harm.  They will
        // be consolidated during the partial view traversal.  So,
        // just create an list - garbage in, garbage out.
        return Collections.unmodifiableList(Arrays.asList(values));
    
    }
    

}