empire-db-jsf2/src/main/java/org/apache/empire/jsf2/components/ValueTag.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 org.apache.empire.jsf2.components;

import java.io.IOException;

import javax.faces.component.UIOutput;
import javax.faces.context.FacesContext;
import javax.faces.context.ResponseWriter;

import org.apache.empire.commons.ObjectUtils;
import org.apache.empire.commons.StringUtils;
import org.apache.empire.data.DataType;
import org.apache.empire.jsf2.controls.InputControl;
import org.apache.empire.jsf2.utils.TagEncodingHelper;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class ValueTag extends UIOutput // implements NamingContainer
{

    // Logger
    private static final Logger log = LoggerFactory.getLogger(ValueTag.class);
    
    protected final TagEncodingHelper helper = new TagEncodingHelper(this, "eVal");

    public ValueTag()
    {
        log.trace("component value created");
    }

    @Override
    public String getFamily()
    {
        return "javax.faces.NamingContainer";
    }

    @Override
    public void encodeBegin(FacesContext context)
        throws IOException
    {

        // add label and input components when the view is loaded for the first time
        super.encodeBegin(context);
        
        helper.encodeBegin();
        InputControl control = helper.getInputControl();
        InputControl.ValueInfo vi = helper.getValueInfo(context);

        // render components
        ResponseWriter writer = context.getResponseWriter();
        String tag = writeStartElement(vi, writer);
        control.renderValue(vi, writer);
        if (tag != null)
            writer.endElement(tag);
    }

    protected String writeStartElement(InputControl.ValueInfo vi, ResponseWriter writer)
        throws IOException
    {
        // Map<String, Object> map = getAttributes();
        String tag   = helper.getTagAttributeString("tag");
        Object title = helper.getTagAttributeValue("title");
        // Check
        if (tag == null && title == null && helper.getTagAttributeValue("styleClass")==null)
            return null;
        // Write tag
        if (StringUtils.isEmpty(tag))
            tag="span";
        writer.startElement(tag, this);
        // Detect type and additional style
        String addlStyle = null;
        DataType dataType = vi.getColumn().getDataType();
        if (dataType.isNumeric())
        {   try {
                Object val = helper.getDataValue(true);
                if (val!=null && ObjectUtils.getLong(val)<0)
                    addlStyle = "eValNeg";
            } catch(Exception e) {
                log.warn("Unable to detect sign of numeric value {}. Message is {}!", vi.getColumn().getName(), e.getMessage());
            }
        }
        // render attributes
        helper.writeAttribute(writer, "class", helper.getTagStyleClass(dataType, addlStyle));
        helper.writeAttribute(writer, "style", helper.getTagAttributeString("style"));
        helper.writeAttribute(writer, "title", helper.getValueTooltip(title));
        return tag;
    }

}