utility

Fixing Postgresql Error, “initdb: could not change permissions of directory, Permission denied”

Today im trying to install postgresql 9.3 on my windows server 2003 ( old server actually ), and i found a very weird error. Somehow im unable to complete the installation due to error “could not change permission of directory, permission denied”. Below is the complete error stacktrace,

fixing permissions on existing directory D:/PostgreSQL/9.1/data ... 
initdb: could not change permissions of directory 
"D:/PostgreSQL/9.1/data": Permission denied 

Called Die(Failed to initialise the database cluster with initdb)... 
Failed to initialise the database cluster with initdb 

Script stderr: 
  Program ended with an error exit code 

It happen even after i put the installation folder outside “Program Files” folder, due to windows’ Program Files permission folder setting.

After several hours trying, i found out that the workaround is actually simple. I just create a new folder, i named it “dodol” set the permission to “everyone” and install my postgresql into that folder.

postgresql folder installation
postgresql folder installation

And my postgresql is installed without any problem.

Logging HTTP Request Parameters using HTTP Servlet

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

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,
jxls excel template

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,
jxls netbeans project

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

Have fun with JXLS 🙂

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

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 

How to Inserting 0 To an AutoIncreament Field on MySql

Let say i have this table,

CREATE TABLE `refproductscale` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `scale` varchar(255) NOT NULL,
  `del` set('y','n') NOT NULL DEFAULT 'n',
  PRIMARY KEY (`id`)
)

I dont know why, but everytime im inserting ‘zero’ as its id, suddenly it changes into an increament number.
But with this script, im able to insert ‘zero’ as its id. This is my script,

SET SQL_MODE = "NO_AUTO_VALUE_ON_ZERO";
insert into refproductscale values(0, 'none', 'n');

And this is the result,

All i have to do is use NO_AUTO_VALUE_ON_ZERO before i do insert query. 😉