dhaase / property-loader

Original PropertyLoader reworked

Property loader

===============

Table of Contents

What It Is
Quick Start
Postprocessing Features
Advanced Configuration
Usage example
Java Doc

What It Is

The property loader is a java library for managing property configurations.

It supports several property loading strategies and features e.g.:

1. Hierarchical/Ordered Property Loading (Master, User, System properties ....)
2. Property templates
3. Recursive Property Resolution
4. Property encryption

Quick Start

1. Build the lib:

$ maven install

2. Include jar file to your application
3. Add property files eg props.properties to your applications classpath
4. Load properties:

PropertyLoader propertyLoader = new PropertyLoader().withDefaultConfig();

//loads: "props.properties", "props.$hostname.properties", "props.$user.properties"
Properties properties = propertyLoader.load("props")

Postprocessing Features

####1. Variable Resolving

Variables in property values can be defined with

{$...}

Even nested variables are allowed, e.g.:

{$var{$innervar}e}

In the case above, the PropertyLoader will first resolve the inner variable, replace it, then resolve the outer variable.

####2. Includes

In order to include additional properties files from a properties files, add %include as a key with the file basenames separated by commas as its value, e.g.:

%include=file1,file2,file3

####3. Decryption

Encrypted property values that are prefixed with

DECRYPT:

will be decrypted after loading.

Advanced Configuration

The PropertyLoader's default configuration includes default search paths, suffixes and applies all available postprocessing filters.

The default search paths are:

1. the current directory
2. the user's home directory
3. the context classpath

The default suffixes are:

1. local host names
2. the user name
3. 'override'

####1. Search Locations Tell the PropertyLoader to search for properties files at its default locations (/home/user, current directory and context classpath):

propertyLoader.atDefaultLocations()

#####1.1 Folders and URLs Tell the PropertyLoader to search for properties files at custom paths:

propertyLoader.atDirectory(String directory)
propertyLoader.atBaseURL(URL url)
propertyLoader.atCurrentDirectory()
propertyLoader.atHomeDirectory()

#####1.2 Classpath Tell the PropertyLoader to search for properties files in the current thread's classpath:

propertyLoader.atContextClassPath()

This will get the classloader from the current thread and use it to find properties files.

#####1.3 Classloader Tell the PropertyLoader to search for properties files using a custom ClassLoader:

propertyLoader.atClassLoader(ClassLoader classLoader)

#####1.4 Relative To A Class Tell the PropertyLoader to search for properties files relative to the location of a class:

propertyLoader.atRelativeToClass(Class<?> clazz)

####2. Suffixes Tell the PropertyLoader to use default suffixes (local host names, user name and "override"):

propertyLoader.addDefaultSuffixes()

Tell the PropertyLoader to use custom suffixes:

propertyLoader.addSuffix(String directory)
propertyLoader.addSuffixList(List<String> suffixes)
propertyLoader.addUserName()
propertyLoader.addLocalHostNames()

####3. Postprocessing

You can define which postprocessing filters are applied (includes are always processed if the key is present):

propertyLoader.withDefaultFilters() 
propertyLoader.withVariableResolvingFilter() 
propertyLoader.withEnvironmentResolvingFilter() 
propertyLoader.withDecryptingFilter()
propertyLoader.withWarnIfPropertyHasToBeDefined() 
propertyLoader.withWarnOnSurroundingWhitespace() 

Java Doc

Full Java Doc of the code can be found here http://tng.github.io/property-loader/

How to contribute

Please have a look at CONTRIBUTING.md