org.apache.tamaya.format.formats

Class PropertiesXmlFormat

java.lang.Object

org.apache.tamaya.format.formats.PropertiesXmlFormat

All Implemented Interfaces:

ConfigurationFormat

public class PropertiesXmlFormat
extends Object
implements ConfigurationFormat

Implementation of a ConfigurationFormat for xml property files.

See Also:

Properties.loadFromXML(java.io.InputStream)

Constructor Summary

Constructors

Constructor and Description
PropertiesXmlFormat()

Method Summary

Modifier and Type	Method and Description
boolean	accepts(URL url) Allows the format to examine the given resource, e.g. for a matching file ending.
String	getName() Get a unique name of the format.
ConfigurationData	readConfiguration(String resource, InputStream inputStream) Reads a configuration from an URL, hereby parsing the given InputStream.

Methods inherited from class java.lang.Object

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

Constructor Detail

PropertiesXmlFormat

public PropertiesXmlFormat()

Method Detail

getName

public String getName()

Description copied from interface: ConfigurationFormat

Get a unique name of the format. This name can be used to access the format.

Specified by:

getName in interface ConfigurationFormat

Returns:

the (unique) format's name, never null and not empty.

accepts

public boolean accepts(URL url)

Description copied from interface: ConfigurationFormat

Allows the format to examine the given resource, e.g. for a matching file ending. Only, if a format accepts an URL, it will be tried for reading the configuration.

Specified by:

accepts in interface ConfigurationFormat

Parameters:

url - the url to read the configuration data from (could be a file, a server location, a classpath resource or something else, not null.

Returns:

true, if this format accepts the given URL for reading.

readConfiguration

public ConfigurationData readConfiguration(String resource,
                                           InputStream inputStream)

Description copied from interface: ConfigurationFormat

Reads a configuration from an URL, hereby parsing the given InputStream. Dependening on the capabilities of the format the returned ConfigurationData may contain different levels of data:

• Only a default section is returned, since the configuration format does not support hierarchies. This is the case for properties and xml properties.
• Hierarchical formats such as INI, XML and JSON can map each node to a section. Each section can have its own key/value pairs. This allows to map also complex formats in a generic way. A format implementation should then additionally flatten the whole data and store it in a accessible as ConfigurationData.getCombinedProperties(). This allows to use the properties as inout to a default mapping, which is always appropriate as long as no other semnatics are defined in the concrete target scenario.
• More complex custom scenarios should map their configuration data read into different sections. Typically the data will be mapped into different PropertySource instances with different ordinal levels. As an example imagine a custom format that contains sections 'defaults', 'global-defaults', 'application', 'server-overrides'.
• Alternate formats

Summarizing implementations common formats should always provide

• the data organized in sections as useful for the given format. If data is organized in one section, it should be mapped into the DEFAULT section.
• Formats that do provide multiple sections, should always provide a FLATTENED section as well, where all the data is organized as a flattened key/value pairs, enabling a generic mapping to a PropertySource.

If the configuration format only contains entries of one ordinal type, normally only one single instance of PropertySource is returned (the corresponding key/values should end up in the DEFAULT section). Nevertheless custom formats may contain different sections or parts, where each part maps to a different target ordinal (eg defaults, domain config and app config). In the ladder case multiple PropertySources can be returned, each one with its own ordinal and the corresponding entries.

Specified by:

readConfiguration in interface ConfigurationFormat

Parameters:

resource - a descriptive name for the resource, since an InputStream does not have any)

inputStream - the inputStream to read the configuration data from (could be a file, a server location, a classpath resource or something else.

Returns:

the corresponding ConfigurationData containing sections/properties read, never null.

See Also:

PropertySource