org.springframework.boot.loader

Class PropertiesLauncher

java.lang.Object

org.springframework.boot.loader.Launcher

org.springframework.boot.loader.PropertiesLauncher

public class PropertiesLauncher
extends Launcher

Launcher for archives with user-configured classpath and main class via a properties file. This model is often more flexible and more amenable to creating well-behaved OS-level services than a model based on executable jars.

Looks in various places for a properties file to extract loader settings, defaulting to application.properties either on the current classpath or in the current working directory. The name of the properties file can be changed by setting a System property loader.config.name (e.g. -Dloader.config.name=foo will look for foo.properties. If that file doesn't exist then tries loader.config.location (with allowed prefixes classpath: and file: or any valid URL). Once that file is located turns it into Properties and extracts optional values (which can also be provided overridden as System properties in case the file doesn't exist):

• loader.path: a comma-separated list of directories to append to the classpath (containing file resources and/or nested archives in *.jar or *.zip). Defaults to lib (i.e. a directory in the current working directory)
• loader.main: the main method to delegate execution to once the class loader is set up. No default, but will fall back to looking for a Start-Class in a MANIFEST.MF, if there is one in ${loader.home}/META-INF.

Author:

Dave Syer, Janne Valkealahti

Field Summary

Fields

Modifier and Type	Field and Description
static String	ARGS Properties key for default command line arguments.
static String	CONFIG_LOCATION Properties key for config file location (including optional classpath:, file: or URL prefix)
static String	CONFIG_NAME Properties key for name of external configuration file (excluding suffix).
static String	HOME Properties key for home directory.
static String	MAIN Properties key for main class.
static String	PATH Properties key for classpath entries (directories possibly containing jars).
static String	SET_SYSTEM_PROPERTIES Properties key for boolean flag (default false) which if set will cause the external configuration properties to be copied to System properties (assuming that is allowed by Java security).

Constructor Summary

Constructors

Constructor and Description
PropertiesLauncher()

Method Summary

Methods

Modifier and Type	Method and Description
protected ClassLoader	createClassLoader(List<Archive> archives) Create a classloader for the specified archives.
protected String[]	getArgs(String... args)
protected List<Archive>	getClassPathArchives() Returns the archives that will be used to construct the class path.
protected File	getHomeDirectory()
protected String	getMainClass() Returns the main class that should be launched.
static void	main(String[] args)
static String	toCamelCase(CharSequence string)

Methods inherited from class org.springframework.boot.loader.Launcher

createArchive, createClassLoader, createMainMethodRunner, launch, launch

Methods inherited from class java.lang.Object

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

Field Detail

MAIN

public static final String MAIN

Properties key for main class. As a manifest entry can also be specified as Start-Class.

See Also:

Constant Field Values

PATH

public static final String PATH

Properties key for classpath entries (directories possibly containing jars). Defaults to "lib/" (relative to loader home directory).

See Also:

Constant Field Values

HOME

public static final String HOME

Properties key for home directory. This is the location of external configuration if not on classpath, and also the base path for any relative paths in the loader path. Defaults to current working directory ( ${user.dir}).

See Also:

Constant Field Values

ARGS

public static final String ARGS

Properties key for default command line arguments. These arguments (if present) are prepended to the main method arguments before launching.

See Also:

Constant Field Values

CONFIG_NAME

public static final String CONFIG_NAME

Properties key for name of external configuration file (excluding suffix). Defaults to "application". Ignored if loader config location is provided instead.

See Also:

Constant Field Values

CONFIG_LOCATION

public static final String CONFIG_LOCATION

Properties key for config file location (including optional classpath:, file: or URL prefix)

See Also:

Constant Field Values

SET_SYSTEM_PROPERTIES

public static final String SET_SYSTEM_PROPERTIES

Properties key for boolean flag (default false) which if set will cause the external configuration properties to be copied to System properties (assuming that is allowed by Java security).

See Also:

Constant Field Values

Constructor Detail

PropertiesLauncher

public PropertiesLauncher()

Method Detail

getHomeDirectory

protected File getHomeDirectory()

getArgs

protected String[] getArgs(String... args)
                    throws Exception

Throws:

Exception

getMainClass

protected String getMainClass()
                       throws Exception

Description copied from class: Launcher

Returns the main class that should be launched.

Specified by:

getMainClass in class Launcher

Returns:

the name of the main class

Throws:

Exception

createClassLoader

protected ClassLoader createClassLoader(List<Archive> archives)
                                 throws Exception

Description copied from class: Launcher

Create a classloader for the specified archives.

Overrides:

createClassLoader in class Launcher

Parameters:

archives - the archives

Returns:

the classloader

Throws:

Exception

getClassPathArchives

protected List<Archive> getClassPathArchives()
                                      throws Exception

Description copied from class: Launcher

Returns the archives that will be used to construct the class path.

Specified by:

getClassPathArchives in class Launcher

Returns:

the class path archives

Throws:

Exception

main

public static void main(String[] args)
                 throws Exception

Throws:

Exception

toCamelCase

public static String toCamelCase(CharSequence string)