Step 1 : Create a properties file, i.e. key.properties

name=Amit
email=amitpatelinfo@gmail.com

Step 2 : Create a Property reader class. i.e.  PropertyReader.java

package com.ap.util;

import java.util.ResourceBundle;
/**
* Read the properties file.
* @author Amit Patel
*
*/

public class PropertyReader {

private static final ResourceBundle keyBundle = ResourceBundle.getBundle(“key”);

public static String getValueFromKeyFile(String key){

try{

return keyBundle.getString(key);

}catch(Exception ex){

return null;

}

}

}

Step 3 : Use the PropertyReader to read the property file.

String email= PropertyReader.getValueFromKeyFile(“email”);

That’s it. .. Wow you read the property file using few line of code.. Great..!

If memory is not a problem on your server then allocate a large amount of memory, such as 512M or more. Also use the server VM option. EG: (-server -Xms512M -Xmx512M). Usually it is better to set both min and max heap size to the same in server applications.

Accordingly, if you’re using Tomcat (and you’d like to allocate a lot of memory), you can edit the catalina.(bin | sh) file found in the bin directory of your Tomcat installation.

For example, on a Windows machine (where I currently find myself these days), I added the following statement around line 71:

set JAVA_OPTS=%JAVA_OPTS% -server -Xms512M -Xmx512M -XX:MaxPermSize=256m.

Thanks,
Amit

To resolve the permgen space in grails.

1) Open the Command prompt

2) fire the below command on cmd prompt.

set JAVA_OPTS=-XX:MaxPermSize=128m -XX:PermSize=128m -Xms1024m -Xmx1024m -XX:-UseGCOverheadLimit

3) Go to the project directory and fire run-app.

Installing Grails

1) Download Grails from following URL.

http://grails.org/Download

2) Grails Installation

• Extract the archive into an appropriate location; typically C:\grails on Windows.
• Create a GRAILS_HOME environment variable that points to the path where you extracted the archive (eg C:\grails on Windows)
• If you have not set the JAVA_HOME environment variable yet, create JAVA_HOME environment variable that points to the path where you have installed Java
• Append a reference to the “bin” directory within the Grails directory to your PATH variable (eg %GRAILS_HOME%\bin on Windows).
• Type “grails” at the command line, if a help message is displayed you are ready to start using Grails!

3) Grails Command-Line Help

>grails

help:
Usage: grails [target]
Targets:

“create-app” – Create a new grails app
“create-controller” – Create a new controller
“create-service” – Create a new service
“create-domain-class” – Create a new domain class
“create-taglib” – Create a new tag library class
“create-test-suite” – Create a new test suite
“create-job” – Create a quartz scheduled job
“generate-controller” – Generates a controller from a domain class
“generate-views” – Generates the views from a domain class
“generate-all” – Generates all artifacts from a domain class
“test-app” – Run current app’s unit tests
“run-app” – Run the application locally and wait
“create-webtest” – Create the functional test layout
“run-webtest” – Run the functional tests for a running app
“shell” – Opens the Grails interactive command line shell
“console” – Opens the Grails interactive swing console
“war” – Create a deployable Web Application Archive (WAR

4) Create “Hello World!” ApplicationView This Poll

So let’s get started creating our first Grails application. To complete your journey through
creating a “Hello World!” application you’re going to step through the following tasks:

• Execute the grails create-app command to create a basic Grails application.
• Create something called a controller that will handle a web request.
• Use the controller to display some text.
• Run the Grails application and view what you achieved in a web browser.

5) To create our “hello” application we need to run the create-app target. This will prompt
you for the name of the application you wish to create. Enter the word hello and hit the return.

>grails create-app
init-props:
create-app:
[input] Enter application name:
hello

Upon completion, the target will have created the “hello” Grails application and the
necessary directory structure.

6)  start the Grails application by running the following target

run-app

7)  Run application in the browser.

http://localhost:8080/hello