how to use JExcel with spring 3 on google app engine

 

First, i tried org.apache.poi. It works in local but throw exception when i upload it to google app engine. Then i have to to JExcel, it works well till now.

step 1: setup your spring environment for your google app engine, please refer my previous article for this.

step 2: download jexcelapi, what i used is jexcelapi_2_6_12. Then copy jxl.jar into war/WEB-INF/lib/ and add it to build path.

step 3: configure web.xml to add spring configuration as below

    <servlet>
        <servlet-name>web-dispatcher</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>web-dispatcher</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>

step 4: create web-dispatcher-servlet.xml which is required by spring looks like below:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p"
    xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="
        http://www.springframework.org/schema/beans 
        http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
        http://www.springframework.org/schema/context 
        http://www.springframework.org/schema/context/spring-context-3.0.xsd">

    <context:component-scan base-package="com.zpylxapp.controller.html" />

    <bean id="viewResolver"
        class="org.springframework.web.servlet.view.ResourceBundleViewResolver">
        <property name="basename" value="views" />
    </bean>
</beans>

step 5: create views.properties file under your “src” directory and add following configuration

xl.(class)=com.zpylxapp.excel.HomePage

step 6: create com.zpylxapp.excel.HomePage view class

package com.zpylxapp.excel;

import java.util.List;
import java.util.Map;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import jxl.*;
import jxl.write.Label;
import jxl.write.WritableSheet;
import jxl.write.WritableWorkbook;
import org.springframework.web.servlet.view.document.AbstractJExcelView;
public class HomePage extends AbstractJExcelView {

    protected void buildExcelDocument(Map model, WritableWorkbook wb,
            HttpServletRequest request, HttpServletResponse response)
            throws Exception {
        WritableSheet sheet = wb.createSheet("Spring", 0);
        sheet.addCell(new Label(0, 0, "Spring-Excel jexcel"));
        List words = (List) model.get("wordList");
        for (int i = 0; i < words.size(); i++) {
            sheet.addCell(new Label(2 + i, 0, (String) words.get(i)));
        }
    }
}

step 7: create your controller use “return new ModelAndView("xl", map);” as return

@Controller
@RequestMapping("/inventory")
public class InventoryController {

    @RequestMapping(value = "/{item}", method = RequestMethod.GET)
    public ModelAndView getxls(Inventory item) {
        
        Map map = new HashMap();
        List wordList = new ArrayList();
        wordList.add("hello");
        wordList.add("world");
        map.put("wordList", wordList);
        return new ModelAndView("xl", map);
    }
}

step 8: done! try it in your google app engine.

Iphone NSDate and NSDateComponents

 

http://developer.apple.com/iphone/library/documentation/Cocoa/Conceptual/DatesAndTimes/Articles/dtCalendars.html#//apple_ref/doc/uid/TP40003470-SW1

1. use components:fromDate:toDate:options: to determine the temporal difference between two dates in units other than seconds (which you could calculate with the NSDate method timeIntervalSinceDate

NSDate *startDate = ...; 
NSDate *endDate = ...; 
  
NSCalendar *gregorian = [[NSCalendar alloc] 
                 initWithCalendarIdentifier:NSGregorianCalendar]; 
  
NSUInteger unitFlags = NSMonthCalendarUnit | NSDayCalendarUnit; 
  
NSDateComponents *components = [gregorian components:unitFlags 
                                          fromDate:startDate 
                                          toDate:endDate options:0]; 
NSInteger months = [components month]; 
NSInteger days = [components day]; 

2. use the dateByAddingComponents:toDate:options: method to add components of a date (such as hours or months) to an existing date

NSDate *today = [[NSDate alloc] init]; 
NSDateComponents *offsetComponents = [[NSDateComponents alloc] init]; 
[offsetComponents setHour:1]; 
[offsetComponents setMinutes:30]; 
// Calculate when, according to Tom Lehrer, World War III will end 
NSDate *endOfWorldWar3 = [gregorian dateByAddingComponents:comps toDate:today options:0];