Returns a default value if the specified property does not exist : System Properties « Development « Java Tutorial

Java Tutorial

1.	Language
2.	Data Type
3.	Operators
4.	Statement Control
5.	Class Definition
6.	Development
7.	Reflection
8.	Regular Expressions
9.	Collections
10.	Thread
11.	File
12.	Generics
13.	I18N
14.	Swing
15.	Swing Event
16.	2D Graphics
17.	SWT
18.	SWT 2D Graphics
19.	Network
20.	Database
21.	Hibernate
22.	JPA
23.	JSP
24.	JSTL
25.	Servlet
26.	Web Services SOA
27.	EJB3
28.	Spring
29.	PDF
30.	Email
31.	J2ME
32.	J2EE Application
33.	XML
34.	Design Pattern
35.	Log
36.	Security
37.	Apache Common
38.	Ant
39.	JUnit

Java

Java Source Code / Java Documentation

Illustrator Tutorials

GIMP Tutorials

C# / C Sharp

C# / CSharp Tutorial

C# / CSharp Open Source

SQL Server / T-SQL Tutorial

Oracle PL / SQL

Oracle PL/SQL Tutorial

Flash / Flex / ActionScript

VBA / Excel / Access / Word

XML

XML Tutorial

Microsoft Office PowerPoint 2007 Tutorial

Microsoft Office Excel 2007 Tutorial

Microsoft Office Word 2007 Tutorial

Java Tutorial » Development » System Properties

6. 2. 26. Returns a default value if the specified property does not exist

public static String getProperty (String key, String default)


public class MainClass{



  public static void main(String[] args){

     System.out.println(System.getProperty("password","defaultPassword")); 

  }



}

defaultPassword


public class MainClass {



  public static void main(String[] args) {

      System.out.println("  OS name: " + System.getProperty("os.name", "not specified"));

      System.out.println("  JVM Version: " + System.getProperty("java.version", "not specified"));

      System.out.println("  user.home: " + System.getProperty("user.home", "not specified"));

      System.out.println("  java.home: " + System.getProperty("java.home", "not specified"));

  }

}

OS name: Windows XP
JVM Version: 1.5.0
user.home: C:\Documents and Settings\yourname
java.home: C:\Java_Dev\sdk\jdk\jre

6. 2. System Properties
	6. 2. 1.	Java system properties
	6. 2. 2.	Using System.getProperty(String key) to retrieve system properties
	6. 2. 3.	Accessing a single System Properties: user.dir
	6. 2. 4.	Getting the Default System Properties
	6. 2. 5.	Setting System Properties
	6. 2. 6.	Create a user-defined property or change the value of the current property
	6. 2. 7.	Determine operating system using System class
	6. 2. 8.	Get Java specification version using System class
	6. 2. 9.	Get system properties using System class
	6. 2. 10.	Loading Native Code
	6. 2. 11.	Set a system property
	6. 2. 12.	Setting the Value of a System Property from the Command Line: add -D option to the java command when running your program.
	6. 2. 13.	Get Java Runtime Environment (JRE) version
	6. 2. 14.	Get user home directory name
	6. 2. 15.	Get operating system name and version
	6. 2. 16.	Get file separator symbol
	6. 2. 17.	Get path / classpath separator
	6. 2. 18.	Get Java Home directory
	6. 2. 19.	Get username of system current user
	6. 2. 20.	Clear system property: The System.clearProperty() method available in Java 1.5
	6. 2. 21.	Get operating system temporary directory / folder
	6. 2. 22.	Get Environment Variables
	6. 2. 23.	Terminate a Java application
	6. 2. 24.	System.setProperty("apple.laf.useScreenMenuBar", "true")
	6. 2. 25.	Emit a beep by printing the ASCII Bell character to the console
	6. 2. 26.	Returns a default value if the specified property does not exist

www.java2java.com | Contact Us

All other trademarks are property of their respective owners.