Class PropertyResourceBundle

PropertyResourceBundle is a concrete subclass of ResourceBundle that manages resources for a locale using a set of static strings from a property file. See ResourceBundle for more information about resource bundles.

Unlike other types of resource bundle, you don't subclass PropertyResourceBundle. Instead, you supply properties files containing the resource data. ResourceBundle.getBundle will automatically look for the appropriate properties file and create a PropertyResourceBundle that refers to it. See ResourceBundle.getBundle for a complete description of the search and instantiation strategy.

The following example shows a member of a resource bundle family with the base name "MyResources". The text defines the bundle "MyResources_de", the German member of the bundle family. This member is based on PropertyResourceBundle, and the text therefore is the content of the file "MyResources_de.properties" (a related example shows how you can add bundles to this family that are implemented as subclasses of ListResourceBundle). The keys in this example are of the form "s1" etc. The actual keys are entirely up to your choice, so long as they are the same as the keys you use in your program to retrieve the objects from the bundle. Keys are case-sensitive.

# MessageFormat pattern
s1=Die Platte \"{1}\" enthält {0}.

# location of {0} in pattern
s2=1

# sample disk name
s3=Meine Platte

# first ChoiceFormat choice
s4=keine Dateien

# second ChoiceFormat choice
s5=eine Datei

# third ChoiceFormat choice
s6={0,number} Dateien

# sample date
s7=3. März 1996

The implementation of a PropertyResourceBundle subclass must be thread-safe if it's simultaneously used by multiple threads. The default implementations of the non-abstract methods in this class are thread-safe.

Note: PropertyResourceBundle can be constructed either from an InputStream or a Reader, which represents a property file. Constructing a PropertyResourceBundle instance from an InputStream requires that the input stream be encoded in ISO-8859-1. In that case, characters that cannot be represented in ISO-8859-1 encoding must be represented by Unicode Escapes as defined in section 3.3 of The Java™ Language Specification whereas the other constructor which takes a Reader does not have that limitation.

Constructors

PropertyResourceBundle

public PropertyResourceBundle(InputStream stream)
                       throws IOException

Creates a property resource bundle from an InputStream. The property file read with this constructor must be encoded in ISO-8859-1.

Parameters:

stream - an InputStream that represents a property file to read from.

Throws:

IOException - if an I/O error occurs

NullPointerException - if stream is null

IllegalArgumentException - if stream contains a malformed Unicode escape sequence.

PropertyResourceBundle

public PropertyResourceBundle(Reader reader)
                       throws IOException

Creates a property resource bundle from a Reader. Unlike the constructor PropertyResourceBundle(InputStream), there is no limitation as to the encoding of the input property file.

Parameters:

reader - a Reader that represents a property file to read from.

Throws:

IOException - if an I/O error occurs

NullPointerException - if reader is null

IllegalArgumentException - if a malformed Unicode escape sequence appears from reader.

Since:

1.6

Methods

handleGetObject

public Object handleGetObject(String key)

Description copied from class: ResourceBundle

Gets an object for the given key from this resource bundle. Returns null if this resource bundle does not contain an object for the given key.

Specified by:

handleGetObject in class ResourceBundle

Parameters:

key - the key for the desired object

Returns:

the object for the given key, or null

getKeys

public Enumeration<String> getKeys()

Returns an Enumeration of the keys contained in this ResourceBundle and its parent bundles.

Specified by:

getKeys in class ResourceBundle

Returns:

an Enumeration of the keys contained in this ResourceBundle and its parent bundles.

See Also:

ResourceBundle.keySet()

handleKeySet

protected Set<String> handleKeySet()

Returns a Set of the keys contained only in this ResourceBundle.

Overrides:

handleKeySet in class ResourceBundle

Returns:

a Set of the keys contained only in this ResourceBundle

Since:

1.6

See Also:

ResourceBundle.keySet()