When standard tools (java.util.prefs.Preferences) not enough for solving your goals with saving some properties, org.apache.commons.configuration.PropertiesConfiguration can help you.
- Configuration file creation.
private static final Logger LOGGER = LoggerFactory.getLogger(ClientSettings.class)
String propertyPath = "/userdir";
String fileName = "fileName.property";
File propertyDir = new File(propertyPath);
if(!propertyDir.exists()) {
if (!propertyDir.mkdirs()) {
throw new IllegalStateException(String.format("Cannot create property folder: %s", propertyDir.getAbsoluteFile()));
}
}
File propertiesFile = new File(propertyDir, fileName);
if (!propertiesFile.exists()) {
try {
if (!propertiesFile.createNewFile())
throw new IllegalStateException(String.format("Cannot create property file: %s", propertiesFile.getAbsoluteFile()));
} catch (IOException e) {
LOGGER.error("Cannot create configuration file: %s", e);
}
}
- Specify the location of the file this configuration is based on and load the configuration.
try {
//allows to specify the configuration source as a file
configuration.setFile(propertiesFile);
//Locate the specified file and load the configuration.
configuration.load();
//Save the configuration to the specified file.
configuration.save(propertiesFile);
} catch (ConfigurationException e) {
LOGGER.error("Cannot initializing a Configuration object.",e);
return null;
}
The following possibilities exist:
- URLs: With the method
setURL()a full URL to the configuration source can be specified. This is the most flexible way. Note that thesave()methods support only file: URLs. - Files: The
setFile()method allows to specify the configuration source as a file. This can be either a relative or an absolute file. In the former case the file is resolved based on the current directory. - As file paths in string form: With the
setPath()method a full path to a configuration file can be provided as a string. - Separated as base path and file name: This is the native form in which the location is stored. The base path is a string defining either a local directory or a URL. It can be set using the
setBasePath()method. The file name, non surprisingly, defines the name of the configuration file.
The configuration source to be loaded can be specified using one of the methods described above. Then the parameterlessload()method can be called.
- Get String properties.
configuration.getString(String key); - Set properties.
configuration.setProperty(String key, Object value);
configuration.save();
If property with such key is exist, value will be overridden. - Add new property.
configuration.addProperty(String key, Object value);configuration.save();
If property with such key is exist, new property will be add anyway.
