org.jboss.common.beans.property

Class PropertiesValueResolver

java.lang.Object

org.jboss.common.beans.property.PropertiesValueResolver

public class PropertiesValueResolver
extends Object

Parses a string and replaces any references to system properties or environment variables in the string

Author:

Jaikiran Pai (copied from JBoss DMR project), David M. Lloyd

Constructor Summary

Constructors

Constructor and Description
PropertiesValueResolver()

Method Summary

Methods

Modifier and Type	Method and Description
static String	replaceProperties(String value) Replace properties of the form: ${<[env.]name>[,<[env.]name2>[,<[env.]name3>...]][:<default>]} Method inspects given string and replaces all encountered properties.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

PropertiesValueResolver

public PropertiesValueResolver()

Method Detail

replaceProperties

public static String replaceProperties(String value)
                                throws IllegalStateException

Replace properties of the form: ${<[env.]name>[,<[env.]name2>[,<[env.]name3>...]][:<default>]} Method inspects given string and replaces all encountered properties. If method is able to replace all properties, it returns String with replaced values. If it fails to replace property and ${} does not contain default declaration, method throws IllegalStateException.
Example1:

 String toReplace = "userLang=${user.language};user=${env.USER}";
 String result    = "userLang=en;user=santa";
 

Example2:

 String toReplace = "userLang=${IDoneExist,user.language};user=${ImNotThereEither,env.USER}";
 String result    = "userLang=en;user=santa";
 

Example3:

 String toReplace = "userLang=${IDoneExist:user.language};user=${ImNotThereEither,env.USER:defaultWontBeUsed}";
 String result    = "userLang=user.language;user=santa";
 

NOTE: in Example 3 value of userLang in result String. The default value IS NOT RESOLVED. It is used as fallback value.

Parameters:

value - - string containig system or env variable reference(s)

Returns:

the value of the system property or environment variable referenced if it exists

Throws:

IllegalStateException - - thrown when state of properties does not allow to replace all variable references.