App

java.lang.Object
- net.eduvax.util.App

```
public class App
extends java.lang.Object
```
Currently running Application. All main methods should start with App.init() or one subclass equivalent. Should be the only real singleton of application. All other singletons are relative to this one and may be reseted by init method (useful for unit testing and test independence). How to implements singletons using App class :
```
class Singleton {
  public Singleton get() {
      Singleton res=(Singleton)App.get().getSingleton(getClass());
      if (res==null) {
          res=new Singleton();
          CApp.get().setSingleton(res);
      }
                return res;
  }
 }
 
```
warning: in the example above, using getClass() to retrieve singleton permits existence of several instance when effective type is different, ie when subclassing singleton. When singleton is strict over all subclass, do not use getClass() but Singleton.class (to be adapted upon the real Singleton types).

Field Summary

Fields
Modifier and Type	Field and Description
`private static App`	`_app` singleton App instance
`private java.util.Hashtable<java.lang.String,java.lang.String>`	`_attributes` application wide variables.
`private ErrorHandler`	`_errHandler` application wide error tracer
`private ErrHandlerFactory`	`_errHandlerFactory` application wide error handler factory
`private java.util.Locale`	`_locale` Application wide localization
`private SLogger`	`_logger` default logger
`private java.util.Hashtable<java.lang.Class,java.lang.Object>`	`_singletons` singleton set
`private java.io.File`	`_workingDir`
`private static char`	`EE_VB1`
`private static char`	`EE_VB2`
`private static char`	`EE_VE`
`private static int`	`EES_TEXT`
`private static int`	`EES_VB`
`private static int`	`EES_VNAME`

Constructor Summary

Constructors
Modifier Constructor and Description

private App(java.lang.String[] args)
No public constructor.

Constructors
Modifier	Constructor and Description
`private`	`App(java.lang.String[] args)` No public constructor.

Method Summary

Methods
Modifier and Type	Method and Description
`void`	`exit()` Exit application.
`void`	`exit(int cr)` Exit application.
`java.lang.String`	`expandFromAttributes(java.lang.String str)` Expand attribute reference in a String.
`static App`	`get()` singleton getter.
`java.lang.String`	`getAttribute(java.lang.String name)` Gets an attribute or environment variabel value.
`ErrorHandler`	`getErrHandler()` Get app default error handler as dummy handler.
`ErrorHandler`	`getErrHandler(ErrorHandler h)` Create handler from chaining given one to app error tracing handler.
`ErrorHandler`	`getErrHandler(int mode)` Get new handler.
`java.io.File`	`getFile(java.lang.String path)` Get File relative to app pseudo working directory.
`java.util.Locale`	`getLocale()` get current localization
`SLogger`	`getLogger(java.lang.String name)`
`java.util.ResourceBundle`	`getResource(java.lang.String name)` Get resource bundle
`java.lang.Object`	`getSingleton(java.lang.Class type)` Retrieve one singleton
`static long`	`getTimestamp()` Generate a time stamp.
`java.io.File`	`getWorkingDir()` Get current pseudo working directory
`static App`	`init()` Inits net.eduvax.util library.
`static App`	`init(java.lang.String[] args)` Inits net.eduvax.util library.
`SLogger`	`log()` get default logger
`void`	`logPackageInfo(java.lang.Class c)` log package information
`void`	`setAttribute(java.lang.String name, java.lang.String val)` Defines new application attribute.
`private void`	`setAttributesFromArgs(java.lang.String[] args)` Defines attributes from an arguments list.
`void`	`setErrHandlerFactory(ErrHandlerFactory factory)` Change error handler factory.
`void`	`setLocale(java.util.Locale l)` Change localization.
`void`	`setSingleton(java.lang.Class type, java.lang.Object s)` Set singleton instance for type.
`void`	`setSingleton(java.lang.Object s)` Set singleton instance.
`void`	`setUnsetAttribute(java.lang.String name, java.lang.String val)` set attribute only if not already set.
`void`	`setWorkingDir(java.lang.String dirpath)` Change app pseudo working directory
`static void`	`TRACE(java.lang.String msg)` Print trace.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - _app
```
private static App _app
```
    singleton App instance
  - _singletons
```
private java.util.Hashtable<java.lang.Class,java.lang.Object> _singletons
```
    singleton set
  - _logger
```
private SLogger _logger
```
    default logger
  - _errHandler
```
private ErrorHandler _errHandler
```
    application wide error tracer
  - _errHandlerFactory
```
private ErrHandlerFactory _errHandlerFactory
```
    application wide error handler factory
  - _locale
```
private java.util.Locale _locale
```
    Application wide localization
  - _workingDir
```
private java.io.File _workingDir
```
  - _attributes
```
private java.util.Hashtable<java.lang.String,java.lang.String> _attributes
```
    application wide variables. Environment variable complement.
  - EES_TEXT
```
private static final int EES_TEXT
```
    See Also:
    Constant Field Values
  - EES_VB
```
private static final int EES_VB
```
    See Also:
    Constant Field Values
  - EES_VNAME
```
private static final int EES_VNAME
```
    See Also:
    Constant Field Values
  - EE_VB1
```
private static final char EE_VB1
```
    See Also:
    Constant Field Values
  - EE_VB2
```
private static final char EE_VB2
```
    See Also:
    Constant Field Values
  - EE_VE
```
private static final char EE_VE
```
    See Also:
    Constant Field Values
- Constructor Detail
  - App
```
private App(java.lang.String[] args)
```
    No public constructor. Use init() method to create App singleton.
- Method Detail
  - init
```
public static App init(java.lang.String[] args)
```
    Inits net.eduvax.util library.
    
    Parameters:
    args - initialisation arguments. standard use is to provide arguments from program's main method. Arguments matching the -Dname=value pattern are registered as application attributes (as any attribute defined using setAttribute() method).
  - init
```
public static App init()
```
    Inits net.eduvax.util library.
  - get
```
public static App get()
```
    singleton getter. May be null, to avoid this, main method MUST invoke init before anything else.
    
    Returns:
    App unique instance
  - getSingleton
```
public java.lang.Object getSingleton(java.lang.Class type)
```
    Retrieve one singleton
    
    Parameters:
    type - type of singleton
  - setSingleton
```
public void setSingleton(java.lang.Class type,
                java.lang.Object s)
```
    Set singleton instance for type.
    
    Parameters:
    type - type of singleton
    s - new singleton instance
  - setSingleton
```
public void setSingleton(java.lang.Object s)
```
    Set singleton instance. Type is automatically retrieve from effect given object's type. Be care when type is subclassed, this permits creation of one singleton for each subclass, so several instance of parent class... To keep control of singleton type setting, use setSingleton(Class type, Object s).
    
    Parameters:
    s - new singleton instance.
  - log
```
public SLogger log()
```
    get default logger
  - getLogger
```
public SLogger getLogger(java.lang.String name)
```
    Returns:
    new logger
  - logPackageInfo
```
public void logPackageInfo(java.lang.Class c)
```
    log package information
    
    Parameters:
    c - reference class to use as package specifier
  - TRACE
```
public static void TRACE(java.lang.String msg)
```
    Print trace. Print a debug log (using standard format). Message is preceded by TRACE[package.class.method():line_number]. Line number may not be available regarding the compilation debug options.
    
    Parameters:
    msg - message to be printed as trace.
  - getErrHandler
```
public ErrorHandler getErrHandler(int mode)
```
    Get new handler. Create new handler from application own errHandler factory. Returned handler is chained to default error tracing handler.
    
    Parameters:
    mode - error handling mode
    
    Returns:
    error handler
  - getErrHandler
```
public ErrorHandler getErrHandler(ErrorHandler h)
```
    Create handler from chaining given one to app error tracing handler.
    
    Parameters:
    h - handler to chain
  - getErrHandler
```
public ErrorHandler getErrHandler()
```
    Get app default error handler as dummy handler.
    
    Returns:
    app default error handler.
  - setErrHandlerFactory
```
public void setErrHandlerFactory(ErrHandlerFactory factory)
```
    Change error handler factory. Should be set once at application start.
    
    Parameters:
    factory - new error handler factory
  - setLocale
```
public void setLocale(java.util.Locale l)
```
    Change localization.
    
    Parameters:
    l - new locale
  - getLocale
```
public java.util.Locale getLocale()
```
    get current localization
    
    Returns:
    current locale
  - getResource
```
public java.util.ResourceBundle getResource(java.lang.String name)
```
    Get resource bundle
    
    Parameters:
    name - name of resource to load
  - setWorkingDir
```
public void setWorkingDir(java.lang.String dirpath)
```
    Change app pseudo working directory
    
    Parameters:
    dirpath - new path
  - getWorkingDir
```
public java.io.File getWorkingDir()
```
    Get current pseudo working directory
    
    Returns:
    app working directory
  - getFile
```
public java.io.File getFile(java.lang.String path)
```
    Get File relative to app pseudo working directory. Return path is relative to app working directory only when given path is not absolute.
  - exit
```
public void exit(int cr)
```
    Exit application. No System.exit() should be invoke from elsewhere than here...
    
    Parameters:
    cr - exit code
  - exit
```
public void exit()
```
    Exit application. Alias to exit(0).
  - getTimestamp
```
public static long getTimestamp()
```
    Generate a time stamp. Default implementation is current time in milliseconds.
    
    Returns:
    time stamp.
  - setAttribute
```
public void setAttribute(java.lang.String name,
                java.lang.String val)
```
    Defines new application attribute. Value is overwrite when attribute is alreadey defined.
    
    Parameters:
    name - attribute's name
    val - attribute's value
  - setUnsetAttribute
```
public void setUnsetAttribute(java.lang.String name,
                     java.lang.String val)
```
    set attribute only if not already set.
    
    Parameters:
    name - new attribute's name.
    val - new attribute's value.
  - getAttribute
```
public java.lang.String getAttribute(java.lang.String name)
```
    Gets an attribute or environment variabel value. Attribute seach order is: 1st system property (eg env var), 2nd application attribute. The main consequence is, it is not possible to override system attribute with application attributes. An attribute value may contain in its definition a ${attr_name} pattern. When the corresponding attribute name is defines, the pattern is expended with the attribute's value in the resulting string. Expension occurs during getAttribute call, so subsequent calls may return different string if some inclosed attributes values are changing.
    
    Parameters:
    name - attribute's name
    
    Returns:
    attributes value (other attributes reference expanded).
    See Also:
    expandFromAttributes
  - expandFromAttributes
```
public java.lang.String expandFromAttributes(java.lang.String str)
```
    Expand attribute reference in a String. Provide new string by replacing ${attr_name} patterns with attributes value. When a pattern is refering an unknown attribute, the empy string is used for its value (then the effect in reterned string is the pattern appears to have been removed).
    
    Returns:
    expanded String. May be equal to input string if no reference to a an attribute is present in input string.
  - setAttributesFromArgs
```
private void setAttributesFromArgs(java.lang.String[] args)
```
    Defines attributes from an arguments list. Use all -Dname=value found in list as an attribute definition.
    
    Parameters:
    args - arguments to parse.

Class App

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

_app

_singletons

_logger

_errHandler

_errHandlerFactory

_locale

_workingDir

_attributes

EES_TEXT

EES_VB

EES_VNAME

EE_VB1

EE_VB2

EE_VE

Constructor Detail

App

Method Detail

init

init

get

getSingleton

setSingleton

setSingleton

log

getLogger

logPackageInfo

TRACE

getErrHandler

getErrHandler

getErrHandler

setErrHandlerFactory

setLocale

getLocale

getResource

setWorkingDir

getWorkingDir

getFile

exit

exit

getTimestamp

setAttribute

setUnsetAttribute

getAttribute

expandFromAttributes

setAttributesFromArgs