Package org.jvnet.hk2.config

Class ConfigSupport

java.lang.Object
org.jvnet.hk2.config.ConfigSupport
All Implemented Interfaces:
ConfigurationUtilities
@Service public class ConfigSupport extends Object implements ConfigurationUtilities

Helper class to execute some code on configuration objects while taking care of the transaction boiler plate code.

Programmers that wish to apply some changes to configuration objects can use these convenience methods to reduce the complexity of handling transactions.

For instance, say a programmer need to change the HttpListener port from 8080 to 8989, it just needs to do : 

     ... in his code somewhere ...
     HttpListener httpListener = domain.get...

     // If the programmer tries to modify the httpListener directly
     // it will get an exception
     httpListener.setPort("8989"); // will generate a PropertyVetoException

     // instead he needs to use a transaction and can use the helper services
     ConfigSupport.apply(new SingleConfigCode() {
         public Object run(HttpListener okToChange) throws PropertyException {
             okToChange.setPort("8989"); // good...
             httpListener.setPort("7878"); // not good, exceptions still raised...
             return null;
         });

     // Note that after this code
     System.out.println("Port is " + httpListener.getPort());
     // will display 8989
 }
Author:
Jerome Dochez

  • Constructor Details

    • ConfigSupport

      public ConfigSupport()

  • Method Details

    • apply

      public static <T extends ConfigBeanProxy> Object apply(SingleConfigCode<T> code, T param) throws TransactionFailure
      Execute some logic on one config bean of type T protected by a transaction
      Parameters:
      code - code to execute
      param - config object participating in the transaction
      Returns:
      list of events that represents the modified config elements.
      Throws:
      TransactionFailure - when code did not run successfully

    • apply

      public static Object apply(ConfigCode code, ConfigBeanProxy... objects) throws TransactionFailure
      Executes some logic on some config beans protected by a transaction.
      Parameters:
      code - code to execute
      objects - config beans participating to the transaction
      Returns:
      list of property change events
      Throws:
      TransactionFailure - when the code did run successfully due to a transaction exception

    • _apply

      public Object _apply(ConfigCode code, ConfigBeanProxy... objects) throws TransactionFailure
      Executes some logic on some config beans protected by a transaction.
      Parameters:
      code - code to execute
      objects - config beans participating to the transaction
      Returns:
      list of property change events
      Throws:
      TransactionFailure - when the code did run successfully due to a transaction exception

    • getWriteableView

      public <T extends ConfigBeanProxy> T getWriteableView(T source) throws TransactionFailure
      Returns a writeable view of a configuration object
      Parameters:
      source - the configured interface implementation
      Returns:
      the new interface implementation providing write access
      Throws:
      TransactionFailure - if the object cannot be enrolled (probably already enrolled in another transaction).

    • getImpl

      public static ConfigView getImpl(ConfigBeanProxy source)
      Return the main implementation bean for a proxy.
      Parameters:
      source - configuration interface proxy
      Returns:
      the implementation bean

    • proxyType

      public static <T extends ConfigBeanProxy> Class<T> proxyType(T element)
      Returns the type of configuration object this config proxy represents.
      Parameters:
      element - is the configuration object
      Returns:
      the configuration interface class

    • sortAndDispatch

      public static UnprocessedChangeEvents sortAndDispatch(PropertyChangeEvent[] events, Changed target)
      Sort events and dispatch the changes. There will be only one notification of event per event type, per object, meaning that if an object has had 3 attributes changes, the Changed interface implementation will get notified only once.
      Parameters:
      events - of events that resulted of a successful configuration transaction
      target - the intended receiver of the changes notification
      logger - to log any issues.

    • sortAndDispatch

      public static UnprocessedChangeEvents sortAndDispatch(PropertyChangeEvent[] events, Changed target, Logger logger)
      Sort events and dispatch the changes. There will be only one notification of event per event type, per object, meaning that if an object has had 3 attributes changes, the Changed interface implementation will get notified only once.
      Parameters:
      events - of events that resulted of a successful configuration transaction
      target - the intended receiver of the changes notification
      logger - to log any issues.

    • apply

      public void apply(Map<ConfigBean,Map<String,String>> mapOfChanges) throws TransactionFailure
      Throws:
      TransactionFailure

    • getSubElementsTypes

      public static Class<?>[] getSubElementsTypes(ConfigBean bean) throws ClassNotFoundException
      Returns the list of sub-elements supported by a ConfigBean
      Returns:
      array of classes reprensenting the sub elements of a particular
      Throws:
      ClassNotFoundException - for severe errors with the model associated with the passed config bean.

    • getAttributesNames

      public String[] getAttributesNames(ConfigBean bean)
      Returns the list of attributes names by the passed ConfigBean
      Returns:
      array of String for all the attributes names

    • getElementsNames

      public String[] getElementsNames(ConfigBean bean)
      Returns the list of elements names by the passed ConfigBean
      Returns:
      array of String for all the elements names

    • createAndSet

      public static ConfigBean createAndSet(ConfigBean parent, Class<? extends ConfigBeanProxy> childType, Map<String,String> attributes, TransactionCallBack<WriteableView> runnable) throws TransactionFailure
      Creates a new child of the passed child and add it to the parent's live list of elements. The child is also initialized with the attributes passed where each key represent the xml property name for the attribute and the value represent the attribute's value. This code will be executed within a Transaction and can therefore throw a TransactionFailure when the creation or settings of attributes failed. Example creating a new http-listener element under http-service ConfigBean httpService = ... // got it from somwhere. Mapinvalid input: '<'String, String> attributes = new HashMapinvalid input: '<'String, String>(); attributes.put("id", "jerome-listener"); attributes.put("enabled", "true"); ConfigSupport.createAndSet(httpService, HttpListener.class, attributes);
      Parameters:
      parent - parent config bean to which the child will be added.
      childType - child type
      attributes - map of key value pair to set on the newly created child
      Throws:
      TransactionFailure - if the creation or attribute settings failed

    • createAndSet

      public static ConfigBean createAndSet(ConfigBean parent, Class<? extends ConfigBeanProxy> childType, List<AttributeChanges> attributes, TransactionCallBack<WriteableView> runnable) throws TransactionFailure
      Creates a new child of the passed child and add it to the parent's live list of elements. The child is also initialized with the attributes passed where each key represent the xml property name for the attribute and the value represent the attribute's value. This code will be executed within a Transaction and can therefore throw a TransactionFailure when the creation or settings of attributes failed. Example creating a new http-listener element under http-service ConfigBean httpService = ... // got it from somwhere. Mapinvalid input: '<'String, String> attributes = new HashMapinvalid input: '<'String, String>(); attributes.put("id", "jerome-listener"); attributes.put("enabled", "true"); ConfigSupport.createAndSet(httpService, HttpListener.class, attributes);
      Parameters:
      parent - parent config bean to which the child will be added.
      childType - child type
      attributes - list of attribute changes to apply to the newly created child
      runnable - code that will be invoked as part of the transaction to add more attributes or elements to the newly create type
      Throws:
      TransactionFailure - if the creation or attribute settings failed

    • createAndSet

      public static ConfigBean createAndSet(ConfigBean parent, Class<? extends ConfigBeanProxy> childType, Map<String,String> attributes) throws TransactionFailure
      Creates a new child of the passed child and add it to the parent's live list of elements. The child is also initialized with the attributes passed where each key represent the xml property name for the attribute and the value represent the attribute's value. This code will be executed within a Transaction and can therefore throw a TransactionFailure when the creation or settings of attributes failed. Example creating a new http-listener element under http-service ConfigBean httpService = ... // got it from somwhere. Mapinvalid input: '<'String, String> attributes = new HashMapinvalid input: '<'String, String>(); attributes.put("id", "jerome-listener"); attributes.put("enabled", "true"); ConfigSupport.createAndSet(httpService, HttpListener.class, attributes);
      Parameters:
      parent - parent config bean to which the child will be added.
      childType - child type
      attributes - list of attributes changes to apply to the new created child
      Throws:
      TransactionFailure - if the creation or attribute settings failed

    • createAndSet

      public ConfigBean createAndSet(ConfigBean parent, Class<? extends ConfigBeanProxy> childType, List<AttributeChanges> attributes) throws TransactionFailure
      Throws:
      TransactionFailure

    • deleteChild

      public static void deleteChild(ConfigBean parent, ConfigBean child) throws TransactionFailure
      Throws:
      TransactionFailure

    • _deleteChild

      public static void _deleteChild(ConfigBean parent, WriteableView writeableParent, ConfigBean child) throws TransactionFailure
      Unprotected child deletion, caller must start a transaction before calling this method.
      Parameters:
      parent - the parent element
      writeableParent - the writeable view of the parent element
      child - the child to delete
      Throws:
      TransactionFailure - if something goes wrong.

    • convertMapToAttributeChanges

      public static List<AttributeChanges> convertMapToAttributeChanges(Map<String,String> values)

    • getElementTypeByName

      public static Class<? extends ConfigBeanProxy> getElementTypeByName(ConfigBeanProxy parent, String elementName) throws ClassNotFoundException
      Throws:
      ClassNotFoundException

    • revealProxy

      public static <T extends ConfigBeanProxy> T revealProxy(T proxy)
      Unwrap HK2 proxy to ConfigBeanProxy.
      Parameters:
      ConfigBeanProxy - probably proxied by HK2.
      Returns:
      actual ConfigBeanProxy.
      Throws:
      org.glassfish.hk2.api.MultiException - If there was an error resolving the proxy.

    • addChildWithAttributes

      public Object addChildWithAttributes(ConfigBeanProxy param, ConfigBean parent, Class<? extends ConfigBeanProxy> childType, List<AttributeChanges> attributes, TransactionCallBack<WriteableView> runnable) throws TransactionFailure
      Description copied from interface: ConfigurationUtilities
      Adds this child bean to the parent with the given attributes. Does not start or end a configuration transaction
      Specified by:
      addChildWithAttributes in interface ConfigurationUtilities
      Parameters:
      param -
      parent -
      childType -
      attributes -
      runnable -
      Returns:
      Throws:
      TransactionFailure