Package org.jtrim2.taskgraph

package org.jtrim2.taskgraph

Defines the core interface for the task graph execution framework. The framework allows for dynamically defining a computations with arbitrary dependencies and execute the computations without blocking using resources to the fullest.

Building a task graph

1. The possible factories of the computations (called task node factories: TaskFactory) must be declared. These factories only define what is possible to be computed not what actually will be computed.
2. Once the task node factories were defined, some computation must be declared explicitly to be computed.
3. After the initial required computations were declared, the framework will automatically create the task execution graph based on the dependencies of the computations.
4. With the task graph ready, it can be executed, which will eventually notify its CompletionStage after all computations were completed.

Resource constraints

The framework allows restraining resource usage. There are two kinds of resources, the framework recognizes:

• Resources being used only during a computation of a task node and released after the computation terminates. This resource usage can be limited by appropriate selection of the task executors.
• Resources associated with the output of computations. Outputs consume resources up until the point, no computation needs them. The management of such resources is the responsibility of the task graph execution implementation.

See Also:

• TaskGraphDefConfigurer
• TaskGraphExecutors

Related Packages

Package	Description
org.jtrim2.taskgraph.basic	Defines basic implementations of the task graph execution framework.

Class	Description
BuiltGraph	Defines a whole task execution graph.
DependencyErrorHandler	Defines an error handler to be called instead of the associated node computation when the node is not being executed due to a failed dependency.
ExecutionResultType	Defines the possible general outcomes of a task graph execution.
TaskErrorHandler	Defines a callback notified whenever a failure occurs while trying to create or execute a task node.
TaskExecutorAop	Contains utility methods to do task before or after a task node.
TaskFactories	Defines utility methods to implement task node factories.
TaskFactory<R,I>	Defines a factory for creating task node function for the task execution graph.
TaskFactoryConfig<R,I>	Defines a complete definition of a task node factory.
TaskFactoryDefiner	Allows to define task node factories to build a task graph from.
TaskFactoryGroupConfigurer	Defines the configuration of a task node factory.
TaskFactoryKey<R,I>	Defines the key uniquely identifying a particular task node factory.
TaskFactoryProperties	Defines the properties of a task node factory.
TaskFactoryProperties.Builder	The Builder used to create TaskFactoryProperties instances.
TaskFactorySetup<R,I>	Defines a deferred creator of a task node factory.
TaskFactoryWrapper	Defines a task node factory wrapping another task node factory.
TaskGraphBuilder	Defines the initial nodes of the task graph.
TaskGraphBuilderProperties	Defines the properties used to control task graph building (not its execution).
TaskGraphBuilderProperties.Builder	The Builder used to create TaskGraphBuilderProperties instances.
TaskGraphDefConfigurer	Defines how to create task nodes, which is the first step in building a task execution graph.
TaskGraphExecutionException	Defines an exception meaning that a task graph execution failed due to a node's action throwing an exception.
TaskGraphExecutionResult	Defines the result of a task graph execution.
TaskGraphExecutor	Defines a executor which executes an already built task execution graph.
TaskGraphExecutorProperties	Defines the properties used to control task graph execution.
TaskGraphExecutorProperties.Builder	The Builder used to create TaskGraphExecutorProperties instances.
TaskGraphExecutors	Defines factory methods to create a task graph executors.
TaskInputBinder	A TaskInputBinder is used by task node factories to define the inputs of the task node they create.
TaskInputRef<I>	Defines a reference to the input of a task node.
TaskNodeCreateArgs<R,I>	Defines the properties used to create a task node.
TaskNodeKey<R,I>	Defines the key uniquely identifying a particular task node.
TaskNodeProperties	Defines the properties of a task node.
TaskNodeProperties.Builder	The Builder used to create TaskNodeProperties instances.
TaskNodeWrapper	Defines a task node wrapping another task node.
TaskSkippedException	Defines an exception to be thrown when a task execution is skipped but failing to compute a task is not considered an error for the whole computation.