com.github.fge.jsonschema.processing

Class ProcessorChain<IN extends MessageProvider,OUT extends MessageProvider>

java.lang.Object

com.github.fge.jsonschema.processing.ProcessorChain<IN,OUT>

Type Parameters:

IN - the input type for that chain

OUT - the output type for that chain

@Immutable
public final class ProcessorChain<IN extends MessageProvider,OUT extends MessageProvider>
extends Object

A processor chain

This class allows to build a chain out of different Processor instances. Chaining two processors p1 and p2 only requires that the output of p1 be compatible with the input of p2.

The result behaves like a processor itself, so it can be used in other chains as well.

Sample usage:

     final Processor<X, Y> chain = ProcessorChain.startWith(p1)
         .chainWith(p2).chainWith(...).getProcessor();

     // input is of type X
     final Y ret = chain.process(report, X);
 

Note that all instances are immutable: each alteration of the chain returns a new chain. This, for example, will not work:

     final ProcessorChain<X, Y> chain = ProcessorChain.startWith(p1);
     chain.failOnError(); // WRONG!
     chain.getProcessor(); // Will return p1, not p1 with a stop condition
 

Method Summary

Methods

Modifier and Type	Method and Description
<NEWOUT extends MessageProvider> ProcessorChain<IN,NEWOUT>	chainWith(Processor<OUT,NEWOUT> p) Add a processor to the chain
ProcessorChain<IN,OUT>	failOnError() Stop the processing chain on failure
ProcessorChain<IN,OUT>	failOnError(ProcessingMessage message) Stop the processing chain on failure
Processor<IN,OUT>	getProcessor()
static <X extends MessageProvider,Y extends MessageProvider> ProcessorChain<X,Y>	startWith(Processor<X,Y> p) Start a processing chain with a single processor

Methods inherited from class java.lang.Object

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

Method Detail

startWith

public static <X extends MessageProvider,Y extends MessageProvider> ProcessorChain<X,Y> startWith(Processor<X,Y> p)

Start a processing chain with a single processor

Type Parameters:

X - the input type

Y - the output type

Parameters:

p - the processor

Returns:

a single element processing chain

Throws:

NullPointerException - processor is null

failOnError

public ProcessorChain<IN,OUT> failOnError()

Stop the processing chain on failure

Inserting this into a chain will stop the processing chain if the previous processor ended up with an error (ie, ProcessingReport.isSuccess() returns false).

Returns:

a new chain

failOnError

public ProcessorChain<IN,OUT> failOnError(ProcessingMessage message)

Stop the processing chain on failure

Inserting this into a chain will stop the processing chain if the previous processor ended up with an error (ie, ProcessingReport.isSuccess() returns false).

Parameters:

message - the processing message to use

Returns:

a new chain

See Also:

ProcessingMessage.asException(), ProcessingMessage.setExceptionProvider(ExceptionProvider)

chainWith

public <NEWOUT extends MessageProvider> ProcessorChain<IN,NEWOUT> chainWith(Processor<OUT,NEWOUT> p)

Add a processor to the chain

Type Parameters:

NEWOUT - the return type for that new processor

Parameters:

p - the processor to add

Returns:

a new chain consisting of the previous chain with the new processor appended

Throws:

NullPointerException - processor to append is null

getProcessor

public Processor<IN,OUT> getProcessor()