com.luciad.format.metadata.model

LuciadLightspeedClass TLcdCompositeMetadataDecoder

java.lang.Object

com.luciad.format.metadata.model.TLcdCompositeMetadataDecoder

All Implemented Interfaces:

ILcdMetadataDecoder, ILcdInputStreamFactoryCapable

public class TLcdCompositeMetadataDecoder
extends Object
implements ILcdMetadataDecoder, ILcdInputStreamFactoryCapable

Composite implementation of ILcdMetadataDecoder.

Any number of metadata decoders can be added to this composite.

The decodeMetadata(java.lang.String) delegates, in order, to the decoders in the list who can decode the source. See decodeMetadata(String) for details.

Example usage:

To create a composite instance which uses all default available ILcdMetadataDecoder instances, you can use:

    ILcdMetadataDecoder metadataDecoder =
        new TLcdCompositeMetadataDecoder(TLcdServiceLoader.getInstance(ILcdMetadataDecoder.class));

This will use all metadata decoders annotated with the @LcdService annotation.

Since:

2022.1

Nested Class Summary

Nested classes/interfaces inherited from interface com.luciad.format.metadata.model.ILcdMetadataDecoder

ILcdMetadataDecoder.MetadataWithSource

Constructor Summary

Constructors

Constructor and Description
TLcdCompositeMetadataDecoder() Creates a new, empty composite metadata decoder.
TLcdCompositeMetadataDecoder(ILcdMetadataDecoder... aMetadataDecoders) Creates a new composite metadata decoder containing the supplied delegate decoders.
TLcdCompositeMetadataDecoder(Iterable<? extends ILcdMetadataDecoder> aMetadataDecoders) Creates a new composite metadata decoder that lazily uses the given Iterable to delegate to.

Method Summary

Modifier and Type	Method and Description
boolean	canDecodeMetadata(String aSourceName) Tells whether this metadata decoder can likely decode metadata for a given source name.
TLcdISO19115Metadata	decodeMetadata(String aSourceName) Decode the given metadata source through a suitable delegate metadata decoder.
ILcdMetadataDecoder.MetadataWithSource	findAndDecodeMetadata(String aSourceName) Finds and decode additional metadata for the given data source through a suitable delegate metadata decoder.
ILcdInputStreamFactory	getInputStreamFactory() Returns the input stream factory that is used.
List<ILcdMetadataDecoder>	getMetadataDecoders() Returns the list of delegate metadata decoders contained in this composite.
void	setInputStreamFactory(ILcdInputStreamFactory aInputStreamFactory) If not null, overrides the input stream factory of the contained metadata decoders with the given factory.

Methods inherited from class java.lang.Object

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

Constructor Detail

TLcdCompositeMetadataDecoder

public TLcdCompositeMetadataDecoder()

Creates a new, empty composite metadata decoder. This decoder will not be able to create metadata until delegate metadata decoders are added to the model decoder list.

TLcdCompositeMetadataDecoder

public TLcdCompositeMetadataDecoder(Iterable<? extends ILcdMetadataDecoder> aMetadataDecoders)

Creates a new composite metadata decoder that lazily uses the given Iterable to delegate to.

Parameters:

aMetadataDecoders - an Iterable of metadata decoders

TLcdCompositeMetadataDecoder

public TLcdCompositeMetadataDecoder(ILcdMetadataDecoder... aMetadataDecoders)

Creates a new composite metadata decoder containing the supplied delegate decoders.

Parameters:

aMetadataDecoders - delegate decoders to be added to the composite

Method Detail

getMetadataDecoders

public List<ILcdMetadataDecoder> getMetadataDecoders()

Returns the list of delegate metadata decoders contained in this composite. If the factory does not use an Iterable, delegates can be added or removed by modifying this list.

Returns:

the list of delegate metadata decoders in this composite

canDecodeMetadata

public boolean canDecodeMetadata(String aSourceName)

Description copied from interface: ILcdMetadataDecoder

Tells whether this metadata decoder can likely decode metadata for a given source name.

• If true, it is likely that ILcdMetadataDecoder.decodeMetadata(String) will return a non-null TLcdISO19115Metadata object, but it is not a guarantee. The result is optimistic.
• If false, it is guaranteed that ILcdMetadataDecoder.decodeMetadata(String) will throw an exception or return null.

Specified by:

canDecodeMetadata in interface ILcdMetadataDecoder

Parameters:

aSourceName - the source name to decode metadata for

Returns:

true if this metadata decoder can decode metadata for the given source name, false otherwise

decodeMetadata

public TLcdISO19115Metadata decodeMetadata(String aSourceName)
                                    throws IOException

Decode the given metadata source through a suitable delegate metadata decoder.

Notes:

• Tries all delegate decoders that can decode the source, in order.
• The first successfully created non-null metadata is returned.

Decodes the metadata from a given source name as an ISO-19115 metadata object.

Note that even if ILcdMetadataDecoder.canDecodeMetadata(String) returns true, this method may yet not be able to decode the given source name. While returning null is allowed when this decoder couldn't decode the given source name, implementors are advised to throw an error instead.

Specified by:

decodeMetadata in interface ILcdMetadataDecoder

Parameters:

aSourceName - the source for which metadata should be created

Returns:

metadata created by the selected delegate decoder

Throws:

IOException -

• If one or more delegate metadata decoders throw an IOException and no other delegate metadata decoder returns a non-null value, an IOException will be thrown containing every suppressed exception.
• If a delegate decoder throws an InterruptedIOException, the decoding stops and that exception is re-thrown.

findAndDecodeMetadata

public ILcdMetadataDecoder.MetadataWithSource findAndDecodeMetadata(String aSourceName)
                                                             throws IOException

Finds and decode additional metadata for the given data source through a suitable delegate metadata decoder.

Notes:

• Tries all delegate decoders, in order.
• The first successfully created non-null metadata is returned.

Searches metadata files for a given source name and decodes them as an ISO-19115 metadata object. The given source name points to a data set, not to a dedicated metadata file. A return value of null indicates that this decoder could not find dedicated metadata files for the given source name.

This method returns a ILcdMetadataDecoder.MetadataWithSource, which combines the decoded metadata together with the names of the dedicated metadata files which were used for decoding the TLcdISO19115Metadata object. If not null, the decoded metadata should be the result of calling the ILcdMetadataDecoder.decodeMetadata(String) method, passing one of these dedicated metadata files.

The default implementation returns null.

Specified by:

findAndDecodeMetadata in interface ILcdMetadataDecoder

Parameters:

aSourceName - the data source for which additional metadata files should be searched and decoded

Returns:

metadata created by the selected delegate decoder

Throws:

IOException -

• If one or more delegate metadata decoders throw an IOException and no other delegate metadata decoder returns a non-null value, an IOException will be thrown containing every suppressed exception.
• If a delegate decoder throws an InterruptedIOException, the decoding stops and that exception is re-thrown.

setInputStreamFactory

public void setInputStreamFactory(ILcdInputStreamFactory aInputStreamFactory)

If not null, overrides the input stream factory of the contained metadata decoders with the given factory.

Specified by:

setInputStreamFactory in interface ILcdInputStreamFactoryCapable

Parameters:

aInputStreamFactory - the input stream factory to be used.

getInputStreamFactory

public ILcdInputStreamFactory getInputStreamFactory()

Description copied from interface: ILcdInputStreamFactoryCapable

Returns the input stream factory that is used.

Specified by:

getInputStreamFactory in interface ILcdInputStreamFactoryCapable

Returns:

the input stream factory that is used.