mkyong, Author at Mkyong.com

Remove all default CSS styling from PrimeFaces

August 28, 2012August 15, 2012 by mkyong

By default, PrimeFaces will return total of four files, 2 css files and 2 Javascript files. <link type="text/css" rel="stylesheet" href="/primefaces/faces/javax.faces.resource/theme.css?ln=primefaces-aristo" /> <link type="text/css" rel="stylesheet" href="/primefaces/faces/javax.faces.resource/primefaces.css?ln=primefaces" /> <script type="text/javascript" src="/primefaces/faces/javax.faces.resource/jquery/jquery.js?ln=primefaces"></script> <script type="text/javascript" src="/primefaces/faces/javax.faces.resource/primefaces.js?ln=primefaces"></script> Some people don’t like the default PrimeFaces CSS file and wonder how to remove it? Solution You are allow to remove only the …

Create a custom theme in PrimeFaces

November 7, 2012August 14, 2012 by mkyong

PrimeFaces is using jQuery ThemeRoller framework, and it comes with 30+ pre-defined themes, visit all available themes, before create a custom theme. In this tutorial, we will show you how to create a custom theme and apply it in PrimeFaces. 1. ThemeRoller CSS Framework Visit jQuery ThemeRoller, play around the value to customize your theme, …

Changing theme in PrimeFaces

August 13, 2012 by mkyong

PrimeFaces is using jQuery ThemeRoller CSS theme framework, and come with 30+ pre-designed themes that you can download and apply in seconds. In this tutorial, we will show you how to change a theme n PriceFaces. There are two ways to change a theme : Using Maven to download and apply. Download manually and apply. …

Generate getters and setters in Eclipse IDE

August 12, 2012 by mkyong

Still busy writing setters and getters method manually? Actually, Eclipse IDE is able to help you generate the setters and getters method automatically, and this feature is bundle with Eclipse IDE long time ago, surprisingly, many Java developers are not aware of it? See following steps to show you how. 1. Java Pojo A simple …

PrimeFaces : java.io.IOException: Not in GZIP format

August 28, 2012August 11, 2012 by mkyong

Recently, testing on PrimeFaces’ idleMonitor component. <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml" xmlns:h="http://java.sun.com/jsf/html" xmlns:f="http://java.sun.com/jsf/core" xmlns:ui="http://java.sun.com/jsf/facelets" xmlns:p="http://primefaces.org/ui"> <h:head> </h:head> <h:body> <h1>PrimeFaces and idleMonitor</h1> <p:growl id="messages" showDetail="true" sticky="true" /> <p:idleMonitor timeout="10000" update="messages"> <p:ajax event="idle" listener="#{idleBean.idleListener}" update="messages" /> </p:idleMonitor> </h:body> </html> Problem After 10 seconds, console prompts java.io.IOException: Not in GZIP format? That’s weird, what GZIP to do iwith idleMonitor …

PrimeFaces code completion in Eclipse IDE

August 10, 2012 by mkyong

In Eclipse, as long as your JSF + PrimeFaces project with JSF facet enabled, the PrimeFaces code completion is available automatically. Figure : PrimeFaces code assist in Eclipse IDE Tools Tested : JSF 2.1.11 Eclipse 4.2 PrimeFaces 3.3 Figure : Steps to enable JSF facet in Eclipse IDE. For detail instruction to configure JSF facet, …

PrimeFaces idleMonitor example

October 9, 2012August 8, 2012 by mkyong

The idleMonitor component, monitor user action and fire when user goes idle or active again. By default, the idle time is set to 5 minutes (300000 ms), and you can customize the duration via timeout attribute like below : <!– fire if user idle for 10 seconds –> <p:idleMonitor timeout="10000" onidle="idleDialog.show()" /> In this tutorial, …

GAE + Python hello world on Mac OS X

August 28, 2012August 6, 2012 by mkyong

In this tutorial, we will show you how to create a simple GAE hello world web project, using Python, on Mac OS X, and run it via Google App Engine Launcher. Tools used : Google App Engine SDK for Python (Mac OS X) – 1.7.0 Mac OS X 10.8 Python 2.7 Note By default, Mac …

How to find large file size on Mac OS X

August 28, 2012August 5, 2012 by mkyong

In this tutorial, we show you two ways to find large files on Mac OS X. Built-in search tools Find command 1. Search Tools To open the search tools, do following : Mac OS X Desktop, run Finder. Press Command+F to open “Search Tools” (it also can be located from menu -> File -> Find). …

PrimeFaces hello world example

August 29, 2012August 3, 2012 by mkyong

In this tutorial, we will show you how to create a JSF 2 + PrimeFaces wed project, the final output is display a “hello world” string in PrimeFaces editor component. Tools used : JSF 2.1.11 Primefaces 3.3 Eclipse 4.2 Maven 3 Tested on Tomcat 7 Note PrimeFaces only requires a JAVA 5+ runtime and a …

sed command hits “undefined label” error on Mac OS X

August 2, 2012 by mkyong

See following scenario, create a file, add content, search and replace it. $ touch testing.txt $ echo "this is mkyong.com" > testing.txt $ cat testing.txt this is mkyong.com $ sed -i ‘s/mkyong/google/g’ testing.txt sed: 1: "testing.txt": undefined label ‘esting.txt’ This sed -i ‘s/mkyong/google/g’ testing.txt command is working properly in Linux, but hits “undefined label” error …

How to list all Jobs in the Quartz Scheduler

August 29, 2012August 2, 2012 by mkyong

Below are two code snippets to show you how to list all Quartz jobs. Quartz 2 APIs are changed a lot, so syntax is different from Quartz 1.x. 1. Quartz 2.1.5 example Scheduler scheduler = new StdSchedulerFactory().getScheduler(); for (String groupName : scheduler.getJobGroupNames()) { for (JobKey jobKey : scheduler.getJobKeys(GroupMatcher.jobGroupEquals(groupName))) { String jobName = jobKey.getName(); String jobGroup …

How to get ServletContext in JSF 2

August 29, 2012August 1, 2012 by mkyong

The ServletContext class is important in web application, often times, you need this class get the information of current deployed servlet container. Here’s a trick to show you how to get ServletContext in JSF2, via FacesContext. ServletContext servletContext = (ServletContext) FacesContext .getCurrentInstance().getExternalContext().getContext(); References ServletContext JavaDoc FacesContext JavaDoc

How to trigger a Quartz job manually (JSF 2 example)

August 29, 2012August 1, 2012 by mkyong

In Quartz, you can trigger a job manually via following pattern : JobKey jobKey = new JobKey(jobName, jobGroup); scheduler.triggerJob(jobKey); //trigger a job by jobkey In this tutorial, we will show you a JSF 2 web application, display all the Quartz jobs on dataTable, and allow user to click a link o fire the job manually. …

How to find a file in linux

November 13, 2012July 31, 2012 by mkyong

In *nix, you can use the find command to find a file easily. $find {directory-name} -name {filename} 1. Find a file in the root directory If you have no idea where the file is located, you can search the entire system via the “/” root directory. Below example shows you how to find a file, …

Example to run multiple jobs in Quartz

August 29, 2012July 30, 2012 by mkyong

In this example, we show you how to declare multiple Quartz jobs via Quartz APIs, Quartz XML and Spring. In Quartz scheduler framework, each job will be attached to an unique trigger, and run it by scheduler. P.S In Quartz, one trigger for multiple jobs is not possible. (Correct me if this is wrong.) 1. …

Quartz Scheduler Tutorial

August 29, 2012July 28, 2012 by mkyong

Quartz, is a open source job scheduling framework, that let you scheduler a task to run on a predefine date and time. Happy learning Quartz 🙂 1. Quick Start Hello world to Quartz scheduler frameworks. Quartz 1.6 hello world example The old and popular Quartz 1.6.3, legacy system may still using this. Quartz 2 hello …

JSF 2 + Quartz 2 example

August 29, 2012July 27, 2012 by mkyong

In this tutorial, we show you how to run a Quartz job during JSF web application via QuartzInitializerListener listener class in Quartz library. This solution is not only works with JSF 2, the concept is applicable on almost all standard Java web application. Tools Used : JSF 2.1.11 Quartz 2.1.5 Maven 3 Eclipse 4.2 Tomcat …

IncompatibleClassChangeError : JobDetailBean has interface org.quartz.JobDetail as super class

August 29, 2012July 25, 2012 by mkyong

Developing Quartz 2.1.5 + Spring 3.1.2.RELEASE, hits following error messages : Caused by: java.lang.IncompatibleClassChangeError: class org.springframework.scheduling.quartz.JobDetailBean has interface org.quartz.JobDetail as super class at java.lang.ClassLoader.defineClass1(Native Method) at java.lang.ClassLoader.defineClassCond(ClassLoader.java:631) at java.lang.ClassLoader.defineClass(ClassLoader.java:615) at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:141) at org.apache.catalina.loader.WebappClassLoader.findClassInternal(WebappClassLoader.java:2901) at org.apache.catalina.loader.WebappClassLoader.findClass(WebappClassLoader.java:1170) at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1678) at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1556) at org.springframework.util.ClassUtils.forName(ClassUtils.java:258) … 19 more Solution Quartz 2 APIs are changed a lot, and someone already …

java.lang.ClassNotFoundException: org.springframework.transaction.TransactionException

August 29, 2012July 25, 2012 by mkyong

Developing Quartz with Spring 3, and hits following error message. Caused by: java.lang.NoClassDefFoundError: org/springframework/transaction/TransactionException at java.lang.Class.getDeclaredConstructors0(Native Method) at java.lang.Class.privateGetDeclaredConstructors(Class.java:2389) at java.lang.Class.getConstructor0(Class.java:2699) at java.lang.Class.getDeclaredConstructor(Class.java:1985) ….. Caused by: java.lang.ClassNotFoundException: org.springframework.transaction.TransactionException at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1711) at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1556) … 29 more Solution Doesn’t matter with Quartz, above error message show that you need Spring transaction dependency. To fix it, just include …

Eclipse IDE – Tomcat version 6.0 only supports J2EE 1.2, 1.3, 1.4, and Java EE 5 Web modules

August 29, 2012July 20, 2012 by mkyong

Problem Import a Java web project in Eclipse, build with Maven, once create a Tomcat server instance, unable to add the Java web project, and showing Tomcat version 6.0 only supports J2EE 1.2, 1.3, 1.4, and Java EE 5 Web modules Tools used : Eclipse Juno 4.2 Tomcat 6.0.35 JDK 1.6 Solution In project, “.settings” …

jQuery – watermark effect on text input

July 20, 2012July 19, 2012 by mkyong

A simple jQuery example to show you how to implement a watermark text effect on an input field. 1. Code Snippets An email input field and css watermark class. <style type="text/css"> input.watermark { color: #999; } //light silver color </style> <label>Email : </lable> <input id="email" type="text" /> jQuery to apply the watermark effect on email …

Quartz 2 JobListener example

August 29, 2012July 18, 2012 by mkyong

In this tutorial, we will show you how to create a JobListener, to keep track the running jobs status, like when the job is finished. P.S This example is tested with Quartz 2.1.5 1. Quartz Job Job, print a simple message, and throw a JobExecutionException for testing. File : HelloJob.java package com.mkyong.quartz; import org.quartz.Job; import …

Quartz 2 scheduler tutorial

August 29, 2012July 17, 2012 by mkyong

Quartz, enterprise scheduler job framework, to help Java application to scheduler a job/task to run at a specified date and time. This tutorial show you how to develop a scheduler job using latest Quartz library 2.1.5. Note Quartz 2 involves significant API changed, read this for older Quartz 1.6.3 example. 1. Download Quartz You can …

How to install Maven on macOS

January 19, 2021July 16, 2012 by mkyong

By default, Maven 3 is installed on Mac OSX.

Java and zip code example

July 9, 2012 by mkyong

Recently, answered an question about leading zero problem ZipCode, what is the most proper data type for country’s zip code? 1. ZipCode – int In Java, some claimed it should declare as “int”, and use DecimalFormat to format and display the leading zero. For example, package com.mkyong; import java.text.DecimalFormat; public class ZipCodeExample { public static …

Quartz : org.quartz.SchedulerConfigException: Thread count must be > 0

August 29, 2012July 7, 2012 by mkyong

Working with Quartz 2, when running the project, hits following error message? org.quartz.SchedulerConfigException: Thread count must be > 0 at org.quartz.simpl.SimpleThreadPool.initialize(SimpleThreadPool.java:245) at org.quartz.impl.StdSchedulerFactory.instantiate(StdSchedulerFactory.java:1255) at org.quartz.impl.StdSchedulerFactory.getScheduler(StdSchedulerFactory.java:1484) at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4791) at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5285) at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150) at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1559) at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1549) at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303) at java.util.concurrent.FutureTask.run(FutureTask.java:138) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) at java.lang.Thread.run(Thread.java:680) Solution You have defined a “quartz.properties” file, and override the …

How to get URL content in Java

July 4, 2012 by mkyong

In this Java example, we show you how to get content of a page from URL “mkyong.com” and save it into local file drive, named “test.html”. package com.mkyong; import java.io.BufferedReader; import java.io.BufferedWriter; import java.io.File; import java.io.FileWriter; import java.io.IOException; import java.io.InputStreamReader; import java.net.MalformedURLException; import java.net.URL; import java.net.URLConnection; public class GetURLContent { public static void main(String[] args) …

Google App Engine Tutorial

August 7, 2012May 19, 2012 by mkyong

Google App Engine, a cloud computing platform for hosting web application in existing Google infrastructure, it’s easy to scale, manage and free to use up to a predefined consumed resources, and it supports Java. For additional charged, please refer to this GAE billing . In this series of tutorials, we will show you a list …

Google App Engine + JDO + Spring MVC, CRUD example

August 29, 2012May 17, 2012 by mkyong

Note This tutorial is more on practice guide, please refer to this official Using JDO in datastore for detail explanation. See following code snippets to perform CRUD on GAE datastore, using Java Data Objects(JDO). Just annotate the Customer with JDO annotation and perform the CRUD via PersistenceManager. Add Customer c = new Customer(); c.setName(name); PersistenceManager …

Google App Engine + Spring MVC, CRUD example with datastore low level api

August 29, 2012May 15, 2012 by mkyong

GAE datastore Refer to this official “Using datstore guide” to understand what is GAE datastore. See following code snippets to perform CRUD for Google App Engine datastore, Java, using low-level API. Add Store a customer into datastore, with “name” as the key. Key customerKey = KeyFactory.createKey("Customer", "your name"); Entity customer = new Entity("Customer", customerKey); customer.setProperty("name", …

Cron job on Google App Engine for Java

August 29, 2012May 10, 2012 by mkyong

In this tutorial, we will show you how to create a scheduler task or cron job on Google App Engine, for Java. In GAE, cron job uses HTTP GET request to call an URL, the duration of the cron job running time is limited to run up to 10 minutes only, if excess, GAE kill …

Download / export Google App Engine Logs, Java App

August 29, 2012May 10, 2012 by mkyong

In GAE, Java App, you can use command “appcfg request_logs” to download or export the logs from GAE to your computer, see signature below : AppCfg [options] request_logs <app-dir> <output-file> You can type “appcfg request_logs” to view all available options. 1. What is <app-dir> ? This is NOT your app_id nor any deployed web path …

Configure logging in Google App Engine

August 29, 2012May 8, 2012 by mkyong

Google App Engine for Java is using java.util.logging.Logger to perform the logging. In this tutorial, we show you how to do logging in GAE environment. 1. Logging Example Example to define a logger in MovieController, and log the messages in different logging levels (info, warning and error) import java.util.logging.Logger; //… @Controller @RequestMapping("/movie") public class MovieController …

Add maxlength on textArea using jQuery

August 29, 2012May 3, 2012 by mkyong

The “maxlength” attribute is not supported in textArea, but you can use JavaScript to limit the length of textArea dynamically. HTML 5 The textArea “maxlength” attribute is supported in HTML 5, the problem is not all browsers support HTML 5, especially, the old IE. jQuery Example A jQuery example to implement the “maxlength” effect on …

Google App Engine + Spring 3 MVC REST example

October 5, 2012April 30, 2012 by mkyong

In this tutorial, we will show you how to develop and deploy a Spring 3.0 MVC REST web application in Google App Engine (GAE) environment. Tools and technologies used : Google App Engine Java SDK 1.6.3.1 Spring 3.1.1 JDK 1.6 Eclipse 3.7 + Google Plugin for Eclipse Note This example is going to reuse this …

Convert PNG to JPEG image in Java

November 14, 2020April 27, 2012 by mkyong

This article shows how to convert an PNG image format to an JPEG image format in Java. 1. PNG Image Below is a PNG image with a transparent background. 2. Java Convert PNG to JPEG Since the JPEG image format doesn’t support the transparent background, we will create a white background as a replacement. Below …

How to install gcc compiler on Mac OS X

August 29, 2012April 26, 2012 by mkyong

Often times, you need c or gcc compiler to compile open source projects in Mac OS X. The problem is Mac OS X doesn’t install the gcc compiler by default. If you try to install or compile some projects that required c/gcc compiler, following errors message will be logged : configure: error: C compiler cannot …

Google App Engine + JSF 2 example

April 25, 2012 by mkyong

In this tutorial, we will show you how to develop and deploy a JSF 2.0 web application in Google App Engine (GAE) environment. Tools and technologies used : JDK 1.6 Eclipse 3.7 + Google Plugin for Eclipse Google App Engine Java SDK 1.6.3.1 JSF 2.1.7 Note This example is going to reuse this JSF 2.0 …

GAE + JSF : View /hello.xhtml could not be restored

April 24, 2012 by mkyong

Problem Deployed on GAE production environment, when navigate from one page/view to another page/view, GAE shows error message “View xxx could not be restored“? JSF 2.1.7 Google App Engine SDK 1.6.3 P.S No problem at local GAE development. Solution By default, JSF 2 is using server for session management, and it’s not supported in GAE …