javatools.util
Class Props

java.lang.Object
  |
  +--java.util.Dictionary
        |
        +--java.util.Hashtable
              |
              +--java.util.Properties
                    |
                    +--javatools.util.Props

All Implemented Interfaces:

java.lang.Cloneable, java.util.Map, Resetable, java.io.Serializable

public class Props

extends java.util.Properties

implements Resetable

An extended version of Properties class. It allows reading Properties files from the classpath or resource file. It uses ClassLoader.getResourceAsStream to find a properties file, so that means it either has to be on the classpath or bundled into the jar.

It is intended that you only pass a single string to find the properties like "foo". That will cause Props to search for a file called foo.properties. The directory it searches in will be by default the "res/" directory. That means that it will search your classpath or jar file for a file res/foo.properties. If you run your software in different environments you can pass a system property to the java virtual machine called "environment". In that case the searching will descend another directory level. e.g. if you pass -Denvironment=development, then it will first look for a file res/development/foo.properties. If you are using servlets your servlet engine should have a means to pass in system variables.

This makes it easy to integrate properties into your code. All you do is use Props to find a certain class of property, like "foo" and it will take care of where to physically find the file. And you can set up different properties for different environments.

TODO: make it combine the environment and non-environment specific properties into the one set.

See Also:

Serialized Form

Field Summary

Fields inherited from class java.util.Properties

defaults

Method Summary

java.lang.String	getFullName() Returns the full name for this Props.
static java.lang.String	getLocalConfigDir() Returns the local configuration directory.
void	load() Loads properties.
void	loadLocalConfig() Loads local configuration file.
void	loadResources() Loads resources (aka properties).
void	reset() Resets all this Props.
static Props	singleton(java.lang.String name) Returns a brand new Props object referencing properties of the given name.
void	store() Stores properties in a file.

Methods inherited from class java.util.Properties

getProperty, getProperty, list, list, load, propertyNames, save, setProperty, store

Methods inherited from class java.util.Hashtable

clear, clone, contains, containsKey, containsValue, elements, entrySet, equals, get, hashCode, isEmpty, keys, keySet, put, putAll, rehash, remove, size, toString, values

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Method Detail

singleton

public static Props singleton(java.lang.String name)
                       throws java.io.IOException

Returns a brand new Props object referencing properties of the given name.

Parameters:

name - The name of properties file to load.

Returns:

The Props object.

Throws:

java.io.IOException - If they cannot be loaded.

getLocalConfigDir

public static java.lang.String getLocalConfigDir()

Returns the local configuration directory.

Returns:

The local configuration directory path.

getFullName

public java.lang.String getFullName()

Returns the full name for this Props.

Returns:

The full name.

reset

public void reset()
           throws ResetException

Resets all this Props.

Specified by:

reset in interface Resetable

Throws:

ResetException - If something goes wrong.

load

public void load()
          throws java.io.IOException

Loads properties.

Throws:

java.io.IOException - If properties cannot be loaded.

store

public void store()
           throws java.io.IOException

Stores properties in a file.

Throws:

java.io.IOException - If properties cannot be stored.

loadLocalConfig

public void loadLocalConfig()
                     throws java.io.IOException

Loads local configuration file.

Throws:

java.io.IOException - If file cannot be found.

loadResources

public void loadResources()
                   throws java.io.IOException

Loads resources (aka properties).

Throws:

java.io.IOException - If properties cannot be loaded.