Programming | edwin's journey

Logging HTTP Request Parameters using HTTP Servlet

By edwin / 6 April 2014 13 June 2014 / Java, Programming / Java, servlet, util, utility, web

This is a servlet filter that i use if i want to log what parameters fired by my REST client, basically it’s just a simple http servlet filter.

package com.edw;

import java.io.IOException;
import java.util.Enumeration;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import org.apache.log4j.Logger;

public class LoggingFilter implements Filter {

    private Logger logger = Logger.getLogger(this.getClass());
    
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
    }

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        
        try {
            HttpServletRequest req = (HttpServletRequest) request;
            
            String uri = req.getRequestURI();
            logger.debug("Requested Resource::"+uri);
            
            Enumeration<String> enumeration = req.getParameterNames();
            
            while(enumeration.hasMoreElements()) {
                String parametername = enumeration.nextElement();
                logger.debug(parametername + " : " +req.getParameter(parametername));
            }
        } catch (Exception e) {
            logger.error(e,e);
        }
        
        chain.doFilter(request, response);
    }

    @Override
    public void destroy() {
    }
}

Add your servlet filer to your web.xml and listen for a specific url request, on this example i listen for requests to /services/ url.

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="3.0" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd">    
    <session-config>
        <session-timeout>
            30
        </session-timeout>
    </session-config>
    
    <filter>
	<filter-name>LogFilter</filter-name>
	<filter-class>
		com.edw.LoggingFilter
	</filter-class>
    </filter>
    <filter-mapping>
            <filter-name>LogFilter</filter-name>
            <url-pattern>/services/*</url-pattern>
    </filter-mapping>    
</web-app>

Create and Exporting A Web-Based Excel Report Using JXLS and SpringMVC

By edwin / 31 March 2014 31 March 2014 / Java, Programming / Java, report, util, utility, web

Today im trying to create a simple excel exporter report using SpringMVC. Im integrating JXLS library with SpringMVC framework. I prefer using JXLS compared to JasperReport or other java-to-excel-library due to its easy templating, so i dont need to create excel formatting from java code.

I start with my pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.edw</groupId>
    <artifactId>JXLSSpringMVC</artifactId>
    <version>1.0</version>
    <packaging>war</packaging>

    <name>JXLSSpringMVC</name>

    <properties>
        <endorsed.dir>${project.build.directory}/endorsed</endorsed.dir>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>

    <dependencies>
        <dependency>
            <groupId>javax</groupId>
            <artifactId>javaee-web-api</artifactId>
            <version>6.0</version>
            <scope>provided</scope>
        </dependency>
        
        <!-- Spring 3 dependencies -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-core</artifactId>
            <version>3.1.1.RELEASE</version>
        </dependency> 
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-web</artifactId>
            <version>3.1.1.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>3.1.1.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-tx</artifactId>
            <version>3.1.1.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-orm</artifactId>
            <version>3.1.1.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>cglib</groupId>
            <artifactId>cglib</artifactId>
            <version>2.2</version>
        </dependency>
        <dependency>
            <groupId>commons-codec</groupId>
            <artifactId>commons-codec</artifactId>
            <version>1.9</version>
        </dependency>
        
        <!-- jxls -->
        <dependency>
            <groupId>net.sf.jxls</groupId>
            <artifactId>jxls-core</artifactId>
            <version>0.9.9</version>
        </dependency>
        
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>2.3.2</version>
                <configuration>
                    <source>1.6</source>
                    <target>1.6</target>
                    <compilerArguments>
                        <endorseddirs>${endorsed.dir}</endorseddirs>
                    </compilerArguments>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-war-plugin</artifactId>
                <version>2.1.1</version>
                <configuration>
                    <failOnMissingWebXml>false</failOnMissingWebXml>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-dependency-plugin</artifactId>
                <version>2.1</version>
                <executions>
                    <execution>
                        <phase>validate</phase>
                        <goals>
                            <goal>copy</goal>
                        </goals>
                        <configuration>
                            <outputDirectory>${endorsed.dir}</outputDirectory>
                            <silent>true</silent>
                            <artifactItems>
                                <artifactItem>
                                    <groupId>javax</groupId>
                                    <artifactId>javaee-endorsed-api</artifactId>
                                    <version>6.0</version>
                                    <type>jar</type>
                                </artifactItem>
                            </artifactItems>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>
</project>

And a simple web.xml file

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="3.0" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd">
    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>/WEB-INF/applicationContext.xml</param-value>
    </context-param>
    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>
    <servlet>
        <servlet-name>dispatcher</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <load-on-startup>2</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>dispatcher</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>
    <session-config>
        <session-timeout>
            30
        </session-timeout>
    </session-config>
</web-app>

And 2 SpringMVC configuration file, applicationContext.xml,

<?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"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
        http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd
        http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee-3.0.xsd
        http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd">

    <context:annotation-config/>
    
    <tx:annotation-driven/>
    
    <context:component-scan base-package="com.edw.jxlsspringmvc"/>
    
</beans>

and dispatcher-servlet.xml,

<?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"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
        http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-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.edw.jxlsspringmvc.controller" />
	
    <mvc:annotation-driven />

    <bean id="viewResolver"
          class="org.springframework.web.servlet.view.InternalResourceViewResolver"
          p:prefix="/WEB-INF/jsp/"
          p:suffix=".jsp" />
</beans>

And a simple excel file,

A java controller file,

package com.edw.jxlsspringmvc.controller;

import java.io.FileInputStream;
import java.util.HashMap;
import java.util.Map;
import javax.servlet.ServletContext;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import net.sf.jxls.transformer.XLSTransformer;
import org.apache.poi.ss.usermodel.Workbook;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;

/**
 *
 * @author edwin < edwinkun at gmail dot com >
 */
@Controller
public class IndexController {

    @Autowired
    private ServletContext context;
    
    @RequestMapping(value = "/", method = RequestMethod.GET)
    public String index() {
        return "index";
    }
    
    @RequestMapping(value = "/export", method = RequestMethod.GET)
    public String export(HttpServletRequest request, HttpServletResponse response) {
        try {
            // set output header
            ServletOutputStream os = response.getOutputStream();
            response.setContentType("application/vnd.ms-excel");
            response.setHeader("Content-Disposition", "attachment; filename=\"myexcel.xls\"");
            
            String reportLocation = context.getRealPath("WEB-INF");

            Map beans = new HashMap();
            beans.put("name", "Edwin");
            beans.put("address", "Jakarta, Indonesia");
            XLSTransformer transformer = new XLSTransformer();

            Workbook workbook = transformer.transformXLS(new FileInputStream(reportLocation + "/myexcel.xls"), beans);
            workbook.write(os);
            os.flush();

            return null;
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }    
}

And my index.jsp file

<html>
    <head>
        <title>Download Excel</title>
    </head>
    <body>
        <a href="${pageContext.request.contextPath}/export">download excel</a>
    </body>
</html>

My Netbeans project structure is like this,

And this is the result when im clicking on the website’s download url,

Have fun with JXLS 🙂

Fixing WordPress’ Syntaxhighligther and Bootstrap Incompatibility

By edwin / 3 March 2014 5 March 2014 / CSS, Programming / css, Programming, website

Today’s i just updated my wordpress’ theme, from the old one to a much better one. I like the newer one because it has more flexibility, and also for its responsive design.

But i had an issue, somehow my syntaxhighlighter gives an extra row space and it happen only in Firefox. Here is the screenshot,

Somehow my latest wordpress theme shows incompatibility with Sytaxhighlighter css file. After sometime googling, i found out that i need to override a css property so my Syntaxhighlighter would works.

div.syntaxhighlighter .container:before,div.syntaxhighlighter .container:after {
    content:none;
}

Well i hope it helped others, have fun 🙂

Binding Date Property to SpringMVC’s @ModelAttribute

By edwin / 1 March 2014 1 March 2014 / Java, Programming / Java, Programming, spring, web

Let say i have this java bean,

public class MyBean implements Serializable {
    private Integer id;
    private String userid;       
    private Date contacttime;
	
	// other setter and getter

And i have a SpringMVC Controller like this, using @ModelAttribute as the method’s parameter,

@RequestMapping(value = "/doSomething", method = RequestMethod.POST)
public @ResponseBody Object doSomething(@ModelAttribute MyBean myBean) {
	// do something
}

Im sending HTTP Post which format is like this

id=2&
userid=3abc&
contacttime=130314101010

But it shows error on my server side, which looks like this,

Failed to convert from type java.lang.String to type java.util.Date for value '130314101010'; 
nested exception is java.lang.IllegalArgumentException

Usually, i have to manually use SimpleDateFormat to parse my “ddMMyyHHmmss” String into Date, but SpringMVC provide a very elegant way of handling with this kind of conversion. Just by using @DateTimeFormat

import org.springframework.format.annotation.DateTimeFormat;

public class MyBean implements Serializable {
    private Integer id;
    private String userid;       
	
	@DateTimeFormat(pattern = "ddMMyyHHmmss")
    private Date contacttime;
	
	// other setter and getter

Dont forget to include JodaTime on your pom.xml

<dependency>
	<groupId>joda-time</groupId>
	<artifactId>joda-time</artifactId>
	<version>2.3</version>
</dependency>

If not, you will find this kind of error,

org.springframework.core.convert.ConversionFailedException: Failed to convert from type java.lang.String to type @org.springframework.format.annotation.DateTimeFormat java.util.Date for value '130314101010'; nested exception is java.lang.IllegalStateException: JodaTime library not available - @DateTimeFormat not supported

Have fun with SpringMVC 😀

How to Sniff Network Packages on HPUX Filtered By A Specific IP

By edwin / 26 February 2014 26 February 2014 / nix, Programming / unix, utility

Well on most of Linux distros, it’s very easy sniffing network packages using tcpdump, but on this case i need to sniff packages on HPUX, which doesnt have tcpdump installed.

So basically i have 2 options, install tcpdump on my hpux (which is very tricky because of limitation the sysadmin gave me), or simply by using HPUX’s build function for network sniffing, which is “nettl”.

On this example, im trying to sniff packages to and from a specific ip, first is creating a file which contain the target ip.

filter ip_saddr 192.168.0.11
filter ip_daddr 192.168.0.11

and i save it as /tmp/myfilter.

Next step is running nettl,

#this command is to start nettl
nettl -tn 0x30800000 -e ns_ls_ip -size 1024 -tracemax 99999 -f /tmp/raw.tr

#this command is to check nettl status
nettl -status TRACE

#this command is to filter sniffed network packages using filter
netfmt -N -n -l -c /tmp/myfilter -f /tmp/raw.tr.TRC000 > /tmp/trace.output

#this command is to stop nettl
nettl -tf -e all