htmlinputdaterenderer.java

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/*
 * HtmlInputDateRenderer.java
 * 
 * Created on 2007-9-24, 22:15:06
 * 
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */

package biz.tbuy.common.components.test;

import java.io.IOException;
import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;
import java.util.Map;
import javax.faces.component.EditableValueHolder;
import javax.faces.component.UIComponent;
import javax.faces.component.UIInput;
import javax.faces.context.FacesContext;
import javax.faces.context.ResponseWriter;
import javax.faces.convert.Converter;
import javax.faces.render.Renderer;

/**
 *
 * @author Administrator
 */
public class HtmlInputDateRenderer extends Renderer{

    public HtmlInputDateRenderer() {
        super();
    }

    private static final String MONTH = ".month";
    private static final String DAY = ".day";
    private static final String YEAR = ".year";
    
    // Renderer default values
    private static final int defaultInputFieldSize = 10;
    private static final int defaultStartYear = 1980;
    private static final int defaultEndYear = 2025;
    
    // In a production component, these would be localized names;
    static String monthnames[] = {
        "January", "February", "March", "April", "May", "June",
        "July", "August", "September", "October", "November", "December"
    };
    
    // Rendering begins here
    @Override
    public void encodeBegin(FacesContext fc, UIComponent ui) 
            throws IOException {
        // DEclare threadsafe method variables for current month, day & year
        int currMonth, currDay, monthMaxDay, currYear;
        
        // Initalize current date values
        EditableValueHolder inputdate = (EditableValueHolder)ui;
        Calendar tempcal = new GregorianCalendar();
        
        // Get current value of Date and apply - if null set date to today
        Date dateval = (Date)inputdate.getValue();
        if (dateval != null) {
            tempcal.setTime(dateval);
        } else {
            tempcal.setTime(new java.util.Date());
        }
        currMonth = tempcal.get(Calendar.MONTH);
        currDay = tempcal.get(Calendar.DAY_OF_MONTH);
        monthMaxDay = tempcal.getActualMaximum(Calendar.DAY_OF_MONTH);
        currYear = tempcal.get(Calendar.YEAR);
        
        ResponseWriter rw = fc.getResponseWriter();
        String clientId = ui.getClientId(fc);
        
        encodeInputField(rw, clientId, fc, ui);
        encodeMonthSelect(rw, clientId, ui, currMonth);
        encodeDaySelect(rw, clientId, ui, currDay, monthMaxDay);
        encodeYearSelect(rw, clientId, ui, currYear);
    }
    
    private void encodeInputField(ResponseWriter rw, 
            String clientId, FacesContext fc, UIComponent ui) throws IOException {
        // Render a read-only input field with component's current date value
        rw.startElement("input", ui);
        rw.writeAttribute("name", clientId, "clientId");
        Object val = ((UIInput)ui).getValue();
        // 获得组件的值
        if (val != null) {
            Converter conv = ((UIInput)ui).getConverter();
            // 检查组件是否有转换器
            if (conv != null) {
                // 有则先进行转换再写入
                rw.writeAttribute("value", conv.getAsString(fc, ui, val), "value");
            } else {
                // 否则直接写入值
                rw.writeAttribute("value", val, "value");
            }
        } else {
            // 如果组件无值，则直接写入空值
            rw.writeAttribute("value", "", "value");
        }
        // 获取组件的长度值
        Integer size = (Integer)ui.getAttributes().get("size");
        if (size != null) {
            rw.writeAttribute("size", size, "size");
        } else {
            rw.writeAttribute("size", defaultInputFieldSize, "size");
        }
        rw.writeAttribute("readonly", Boolean.TRUE, null);
        rw.endElement("input");
    }
    
    private void encodeMonthSelect(ResponseWriter rw, 
            String clientId, UIComponent ui, int currMonth) throws IOException {
        rw.startElement("select", ui);
        rw.writeAttribute("size", "1", null);
        rw.writeAttribute("name", clientId + MONTH, null);
        for (int i = 0; i < 12; i++) {
            rw.startElement("option", ui);
            rw.writeAttribute("value", "" + i, null);
            if (i == currMonth) {
                rw.writeAttribute("selected", Boolean.TRUE, null);
            }
            rw.writeText(monthnames[i], null);
            rw.endElement("option");
        }
        rw.endElement("select");
    }
    
    private void encodeDaySelect(ResponseWriter rw, 
            String clientId, 
            UIComponent ui, 
            int currDay, int monthMaxDay) throws IOException {
        rw.startElement("select", ui);
        rw.writeAttribute("size", "1", null);
        rw.writeAttribute("name", clientId + DAY, null);
        for (int i = 0; i < monthMaxDay; i++) {
            rw.startElement("option", ui);
            rw.writeAttribute("value", "" + i, null);
            if (i == currDay) {
                rw.writeAttribute("selected", Boolean.TRUE, null);
            }
            rw.writeText("" + i, null);
            rw.endElement("option");
        }
        rw.endElement("select");
    }
    
    private void encodeYearSelect(ResponseWriter rw, 
            String clientId, UIComponent ui, int currYear) throws IOException{
        Integer startyear = null;
        Integer endyear = null;
        startyear = (Integer)ui.getAttributes().get("startyear");
        if (startyear == null) {
            startyear = new Integer(defaultStartYear);  // 使用默认的年份
        }
        endyear = (Integer)ui.getAttributes().get("endyear");
        if (endyear == null) {
            endyear = new Integer(defaultEndYear);
        }
        rw.startElement("select", ui);
        rw.writeAttribute("size", "1", null);
        rw.writeAttribute("name", clientId + YEAR, null);
        for (int i = startyear; i <= endyear; i++) {
            rw.startElement("option", ui);
            rw.writeAttribute("value", "" + i, null);
            if (i == currYear) {
                rw.writeAttribute("selected", Boolean.TRUE, null);
            }
            rw.writeText("" + i, null);
            rw.endElement("option");
        }
        rw.endElement("select");
    }
    
    /** decode ****************************************************************/
    @Override
    public void decode(FacesContext fc, UIComponent ui) {
        EditableValueHolder inputdate = (EditableValueHolder)ui;
        Map map = fc.getExternalContext().getRequestParameterMap();
        String clientId = ui.getClientId(fc);
        
        Calendar calDate = new GregorianCalendar();
        if (map.containsKey(clientId + MONTH) && 
                map.containsKey(clientId + DAY) &&
                map.containsKey(clientId + YEAR)) {
            int yy = Integer.parseInt((String)map.get(clientId + YEAR));
            int mm = Integer.parseInt((String)map.get(clientId + MONTH));
            int dd = Integer.parseInt((String)map.get(clientId + DAY));
            calDate.set(yy, mm, dd);
            inputdate.setSubmittedValue(calDate.getTime());
        } else {
            inputdate.setSubmittedValue(new java.util.Date());
        }
    }
}