org.ops4j.util.collections
Class PropertiesUtils

java.lang.Object
  org.ops4j.util.collections.PropertiesUtils

public final class PropertiesUtils
extends Object

Utility class supporting operations related to property retrival.

Method Summary

static String	getProperty(Properties props, String key, String def) Return the value of a property.
static String[]	readListFile(URL listFile) Read a file and return the list of lines in an array of strings.
static Properties	readProperties(InputStream stream, Properties mappings, boolean closeStream) Read a set of properties from a property file provided as an Inputstream.
static Properties	readProps(URL propsUrl, Properties mappings) Read a set of properties from a property file specificed by a url.
static String	resolveProperty(Properties props, String value) Resolve symbols in a supplied value against supplied known properties.

Methods inherited from class java.lang.Object

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

Method Detail

readProps

public static Properties readProps(URL propsUrl,
                                   Properties mappings)
                            throws IOException

Read a set of properties from a property file specificed by a url.

Parameters:

propsUrl - the url of the property file to read

mappings - Properties that will be available for translations initially.

Returns:

the resolved properties

Throws:

IOException - if an io error occurs

See Also:

readProperties(java.io.InputStream,java.util.Properties,boolean)

readProperties

public static Properties readProperties(InputStream stream,
                                        Properties mappings,
                                        boolean closeStream)
                                 throws IOException

Read a set of properties from a property file provided as an Inputstream.

Property files may reference symbolic properties in the form ${name}. Translations occur from both the mappings properties as well as all values within the Properties that are being read.

Example;

   Properties mappings = System.getProperties();
   Properties myProps = PropertiesUtils.readProperties( "mine.properties", mappings );
 

and the "mine.properties" file contains;

 mything=${myplace}/mything
 myplace=${user.home}/myplace
 

then the Properties object myProps will contain;

 mything=/home/niclas/myplace/mything
 myplace=/home/niclas/myplace
 

Parameters:

stream - the InputStream of the property file to read.

mappings - Properties that will be available for translations initially.

closeStream - true if the method should close the stream before returning, false otherwise.

Returns:

the resolved properties.

Throws:

IOException - if an io error occurs

resolveProperty

public static String resolveProperty(Properties props,
                                     String value)

Resolve symbols in a supplied value against supplied known properties.

Parameters:

props - a set of know properties

value - the string to parse for tokens

Returns:

the resolved string

getProperty

public static String getProperty(Properties props,
                                 String key,
                                 String def)

Return the value of a property.

Parameters:

props - the property file

key - the property key to lookup

def - the default value

Returns:

the resolve value

readListFile

public static String[] readListFile(URL listFile)
                             throws IOException

Read a file and return the list of lines in an array of strings.

Parameters:

listFile - the url to read from

Returns:

the lines

Throws:

IOException - if a read error occurs