SystemInstance

java.lang.Object
- org.apache.openejb.loader.SystemInstance

```
public final class SystemInstance
extends java.lang.Object
```
This class aims to be the one and only static in the entire system A static, singleton, instance of this class can be created with the init(Properties) method
It is assumed that only one singleton per classloader is possible in any given VM Thus loading this instance in a classloader will mean there can only be one OpenEJB instance for that classloader and all children classloaders.

Examples (en):

webservice-ws-with-resources-config

Examples (pt):

webservice-ws-with-resources-config

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`boolean`	`addObserver(java.lang.Object observer)`
`java.lang.String`	`currentProfile()`
`<E> E`	`fireEvent(E event)`
`static SystemInstance`	`get()`
`FileUtils`	`getBase()`
`java.lang.ClassLoader`	`getClassLoader()`
`ClassPath`	`getClassPath()`
`<T> T`	`getComponent(java.lang.Class<T> type)` I'm not sure how this will play out, but I've used class instances instead of strings for lookups as class instances are classloader scoped and there is an implicit "namespace" associated with that.
`java.io.File`	`getConf(java.lang.String subPath)`
`FileUtils`	`getHome()`
`Options`	`getOptions()`
`java.util.Properties`	`getProperties()`
`java.lang.String`	`getProperty(java.lang.String key)`
`java.lang.String`	`getProperty(java.lang.String key, java.lang.String defaultValue)`
`long`	`getStartTime()`
`boolean`	`hasProperty(java.lang.String propName)`
`static void`	`init(java.util.Properties properties)`
`boolean`	`isDefaultProfile()`
`static boolean`	`isInitialized()`
`<T> T`	`removeComponent(java.lang.Class<T> type)`
`boolean`	`removeObserver(java.lang.Object observer)`
`void`	`removeObservers()`
`static void`	`reset()`
`<T> T`	`setComponent(java.lang.Class<T> type, T value)`
`java.lang.Object`	`setProperty(java.lang.String key, java.lang.String value)`
`java.lang.Object`	`setProperty(java.lang.String key, java.lang.String value, boolean isExternalProperty)`

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

Method Detail

fireEvent
```
public <E> E fireEvent(E event)
```

addObserver

public boolean addObserver(java.lang.Object observer)

removeObserver

public boolean removeObserver(java.lang.Object observer)

getStartTime
```
public long getStartTime()
```

getOptions
```
public Options getOptions()
```

getProperties

public java.util.Properties getProperties()

getProperty

public java.lang.String getProperty(java.lang.String key)

getProperty

public java.lang.String getProperty(java.lang.String key,
                                    java.lang.String defaultValue)

setProperty

public java.lang.Object setProperty(java.lang.String key,
                                    java.lang.String value)

setProperty

public java.lang.Object setProperty(java.lang.String key,
                                    java.lang.String value,
                                    boolean isExternalProperty)

Parameters:: key - property name; value - property value; isExternalProperty - should the property be set to System by System.setProperty(String, String)
Returns:: property value

getHome
```
public FileUtils getHome()
```

getBase
```
public FileUtils getBase()
```

getClassPath
```
public ClassPath getClassPath()
```

getClassLoader

public java.lang.ClassLoader getClassLoader()

getComponent
```
public <T> T getComponent(java.lang.Class<T> type)
```
I'm not sure how this will play out, but I've used class instances instead of strings for lookups as class instances are classloader scoped and there is an implicit "namespace" associated with that. Theoretically, you can't lookup things that you can't already see in your classloader.

Parameters:

type - Class

Returns:

the object associated with the class type or null

Throws:

java.lang.IllegalStateException - of the component isn't found

removeComponent

public <T> T removeComponent(java.lang.Class<T> type)

setComponent

public <T> T setComponent(java.lang.Class<T> type,
                          T value)

Parameters:: type - the class type of the component required

isInitialized
```
public static boolean isInitialized()
```

reset
```
public static void reset()
```

init

public static void init(java.util.Properties properties)
                 throws java.lang.Exception

Throws:: java.lang.Exception

getConf

public java.io.File getConf(java.lang.String subPath)

get
```
public static SystemInstance get()
```

currentProfile

public java.lang.String currentProfile()

isDefaultProfile
```
public boolean isDefaultProfile()
```

hasProperty
```
public boolean hasProperty(java.lang.String propName)
```
Parameters:

propName - property name

Returns:

true when property is set; false otherwise

removeObservers
```
public void removeObservers()
```

Class SystemInstance

Method Summary

Methods inherited from class java.lang.Object

Method Detail

fireEvent

addObserver

removeObserver

getStartTime

getOptions

getProperties

getProperty

getProperty

setProperty

setProperty

getHome

getBase

getClassPath

getClassLoader

getComponent

removeComponent

setComponent

isInitialized

reset

init

getConf

get

currentProfile

isDefaultProfile

hasProperty

removeObservers