Package org.apache.commons.jcs3.utils.config

Class OptionConverter

java.lang.Object

org.apache.commons.jcs3.utils.config.OptionConverter

public class OptionConverter
extends Object

This class is based on the log4j class org.apache.log4j.helpers.OptionConverter that was made by Ceki Gülcü Simon Kitching; Avy Sharell (sharell@online.fr) Anders Kristensen Matthieu Verbert (mve@zurich.ibm.com) A convenience class to convert property values to specific types.

Method Summary

Modifier and Type	Method	Description
static String[]	concatanateArrays(String[] l, String[] r)	Combines two arrays.
static String	convertSpecialChars(String s)	Escapes special characters.
static String	findAndSubst(String key, Properties props)	Find the value corresponding to key in props.
static String	getSystemProperty(String key, String def)	Very similar to System.getProperty except that the SecurityException is hidden.
static <T> T	instantiateByClassName(String className, T defaultValue)	Instantiate an object given a class name.
static <T> T	instantiateByKey(Properties props, String key, T defaultValue)	Creates an object for the className value of the key.
static String	substVars(String val, Properties props)	Perform variable substitution in string val from the values of keys found in the system properties.
static boolean	toBoolean(String value, boolean defaultValue)	If value is "true", then true is returned.
static long	toFileSize(String value, long defaultValue)
static int	toInt(String value, int defaultValue)	Converts to int.

Methods inherited from class java.lang.Object

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

Method Details

concatanateArrays

public static String[] concatanateArrays(String[] l,
 String[] r)

Combines two arrays.

Parameters:

l -

r -

Returns:

String[]

convertSpecialChars

public static String convertSpecialChars(String s)

Escapes special characters.

Parameters:

s -

Returns:

String

getSystemProperty

public static String getSystemProperty(String key,
 String def)

Very similar to System.getProperty except that the SecurityException is hidden.

Parameters:

key - The key to search for.

def - The default value to return.

Returns:

the string value of the system property, or the default value if there is no property with that key.

Since:

1.1

instantiateByKey

public static <T> T instantiateByKey(Properties props,
 String key,
 T defaultValue)

Creates an object for the className value of the key.

Parameters:

props -

key -

defaultValue -

Returns:

Object that was created

toBoolean

public static boolean toBoolean(String value,
 boolean defaultValue)

If value is "true", then true is returned. If value is "false", then true is returned. Otherwise, default is returned. Case of value is unimportant.

Parameters:

value -

defaultValue -

Returns:

Object

toInt

public static int toInt(String value,
 int defaultValue)

Converts to int.

Parameters:

value -

defaultValue -

Returns:

int

toFileSize

public static long toFileSize(String value,
 long defaultValue)

Parameters:

value -

defaultValue -

Returns:

long

findAndSubst

public static String findAndSubst(String key,
 Properties props)

Find the value corresponding to key in props. Then perform variable substitution on the found value.

Parameters:

key -

props -

Returns:

substituted string

instantiateByClassName

public static <T> T instantiateByClassName(String className,
 T defaultValue)

Instantiate an object given a class name. Check that the className is a subclass of superClass. If that test fails or the object could not be instantiated, then defaultValue is returned.

Parameters:

className - The fully qualified class name of the object to instantiate.

defaultValue - The object to return in case of non-fulfillment

Returns:

instantiated object

substVars

public static String substVars(String val,
 Properties props)
                        throws IllegalArgumentException

Perform variable substitution in string val from the values of keys found in the system properties. The variable substitution delimiters are ${ and } . For example, if the System properties contains "key=value", then the call

 String s = OptionConverter.substituteVars( "Value of key is ${key}." );
 

will set the variable s to "Value of key is value.". If no value could be found for the specified key, then the props parameter is searched, if the value could not be found there, then substitution defaults to the empty string. For example, if system properties contains no value for the key "inexistentKey", then the call

 String s = OptionConverter.subsVars( "Value of inexistentKey is [${inexistentKey}]" );
 

will set s to "Value of inexistentKey is []"

An IllegalArgumentExceptionis thrown if val contains a start delimiter "${" which is not balanced by a stop delimiter "}".

Author Avy Sharell

Parameters:

val - The string on which variable substitution is performed.

props -

Returns:

String

Throws:

IllegalArgumentException - if val is malformed.