Package com.luciad.ogc.wcs.client

Class TLcdWCSClient

java.lang.Object

com.luciad.ogc.wcs.client.TLcdWCSClient

public class TLcdWCSClient
extends Object

The TLcdWCSClient class represents a client interface to an OpenGIS WCS server. The supported WCS version is 1.0.0.

A new TLcdWCSClient instance can be created by invoking one of the static factory methods, given a URI of the server or an TLcdWCSCapabilities object representing the server's capabilities. To customize the communication between client and server, an ILcdOWSTransport can optionally be provided. This interface represents the transport layer, and can be used to choose the communication protocol (HTTP GET, HTTP POST, ...), add authentication, or configure any other parameter that relates to the communication channel. By default, an instance of TLcdOWSHttpTransport is used.

Once a TLcdWCSClient instance is initialized, the following requests can be created:

• GetCapabilities: createGetCapabilitiesRequest()
• GetCoverage: createGetCoverageRequest()
• DescribeCoverage: createDescribeCoverageRequest()

To send requests to the server and receive the response, the following methods can be used:

• GetCapabilities: getCachedCapabilities() or getCapabilities(TLcdWCSGetCapabilitiesRequest)
• GetCoverage: getCoverage(TLcdWCSGetCoverageRequest)
• DescribeCoverage: describeCoverage(TLcdWCSDescribeCoverageRequest)

Since:

8.2

See Also:

• TLcdOWSHttpTransport
• TLcdWCSGetCapabilitiesRequest
• TLcdWCSGetCoverageRequest
• TLcdWCSDescribeCoverageRequest

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	TLcdWCSClient(TLcdWCSCapabilities aCapabilities, ILcdOWSTransport aTransport)	Creates a new TLcdWCSClient with the given parameters.
protected	TLcdWCSClient(URI aURI, ILcdOWSTransport aTransport, Object aTransportData)	Creates a new TLcdWCSClient with the given parameters.

Method Summary

Modifier and Type	Method	Description
TLcdWCSDescribeCoverageRequest	createDescribeCoverageRequest()	Creates a new 'DescribeCoverage' request object which is compatible with the WCS version implemented by the WCS server this client communicates with.
TLcdWCSGetCapabilitiesRequest	createGetCapabilitiesRequest()	Creates a new 'GetCapabilities' request object which is compatible with the WCS version implemented by the WCS server this client communicates with.
TLcdWCSGetCoverageRequest	createGetCoverageRequest()	Creates a new 'GetCoverage' request object which is compatible with the WCS version implemented by the WCS server this client communicates with.
static TLcdWCSClient	createWCSClient(TLcdWCSCapabilities aCapabilities, ILcdOWSTransport aTransport)	Creates a new WCS client using the specified capabilities.
static TLcdWCSClient	createWCSClient(URI aURI)	Creates a new WCS client using the specified URI.
static TLcdWCSClient	createWCSClient(URI aURI, ILcdOWSTransport aTransport, Object aTransportData)	Creates a new WCS client using the specified URI.
protected List	decodeOperations(TLcdWCSCapabilities aCapabilities)	Returns a list of TLcdOWSOperation instances based on the contents of the provided TLcdWCSCapabilities instance.
TLcdWCSCoverageDescription	describeCoverage(TLcdWCSDescribeCoverageRequest aRequest)	Performs the 'DescribeCoverage' request.
TLcdWCSCapabilities	getCachedCapabilities()	Returns the most recent capabilities object that was requested by this client.
TLcdWCSCapabilities	getCapabilities(TLcdWCSGetCapabilitiesRequest aRequest)	Performs the 'GetCapabilities' request.
TLcdOWSInputStream	getCoverage(TLcdWCSGetCoverageRequest aRequest)	Performs the 'GetCoverage' request.
protected final TLcdOWSOperation	getOperation(String aOperationName)	Retrieves an operation based on the operation name.
URI	getURI()	Returns the URI of the WCS server.
protected final TLcdOWSInputStream	performRequest(String aOperationName, ILcdOWSRequest aRequest)	Performs a WCS request.
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Details

TLcdWCSClient

protected TLcdWCSClient(TLcdWCSCapabilities aCapabilities,
 ILcdOWSTransport aTransport)
                 throws TLcdOWSDecodingException,
TLcdOWSTransportException,
TLcdOWSServerException,
TLcdOWSUnsupportedVersionException

Creates a new TLcdWCSClient with the given parameters.

Parameters:

aCapabilities - the capabilities of the WCS server

aTransport - the transport to use

Throws:

TLcdOWSDecodingException - if an error occurs while decoding the intial WCS response

TLcdOWSServerException - if an exception report is received from the server

TLcdOWSTransportException - if an error occurs in the transport layer while negotiation the version

TLcdOWSUnsupportedVersionException - if the specified WCS server does not support any of the WCS versions implemented by this client

TLcdWCSClient

protected TLcdWCSClient(URI aURI,
 ILcdOWSTransport aTransport,
 Object aTransportData)
                 throws TLcdOWSDecodingException,
TLcdOWSTransportException,
TLcdOWSServerException,
TLcdOWSUnsupportedVersionException

Creates a new TLcdWCSClient with the given parameters.

Parameters:

aURI - the URI of the WCS server

aTransport - the transport to use

aTransportData - the transport data to use for the initial capabilities requests (may be null)

Throws:

IllegalArgumentException - if the specified URI is not compatible with the specified transport

TLcdOWSDecodingException - if an error occurs while decoding the initial WCS response

TLcdOWSServerException - if an exception report is received from the server

TLcdOWSTransportException - if an error occurs in the transport layer while negotiation the version

TLcdOWSUnsupportedVersionException - if the specified WCS server does not support any of the WCS versions implemented by this client

Method Details

createWCSClient

public static TLcdWCSClient createWCSClient(URI aURI)
                                     throws TLcdOWSTransportException,
TLcdOWSServerException,
TLcdOWSDecodingException,
TLcdOWSUnsupportedVersionException

Creates a new WCS client using the specified URI. The WCS client will use the default transport (HTTP).

Parameters:

aURI - the URI of the WCS server

Returns:

a new WCS client

Throws:

NullPointerException - if the URI is null

IllegalArgumentException - if the specified URI is not compatible with the default transport

TLcdOWSDecodingException - if an error occurs while decoding the intial WCS response

TLcdOWSServerException - if an exception report is received from the server

TLcdOWSTransportException - if an error occurs in the transport layer while negotiation the version

TLcdOWSUnsupportedVersionException - if the specified WCS server does not support any of the WCS versions implemented by this client

See Also:

• createWCSClient(java.net.URI, ILcdOWSTransport, Object)

createWCSClient

public static TLcdWCSClient createWCSClient(TLcdWCSCapabilities aCapabilities,
 ILcdOWSTransport aTransport)
                                     throws TLcdOWSUnsupportedVersionException,
TLcdOWSDecodingException,
TLcdOWSServerException,
TLcdOWSTransportException

Creates a new WCS client using the specified capabilities. The WCS client will use the specified transport. If the version number of the capabilities is supported, a WCS client is initiated with the given capabilities. If the version number is not supported, this method performs the version negotiation process described in the WCS specification. The WCS client returned by this method is guaranteed to be compatible with the WCS version supported by the WCS server. server.

Parameters:

aCapabilities - the capabilities of the WCS server

aTransport - the transport to use

Returns:

a new WCS client

Throws:

NullPointerException - if either the URI or the transport is null

IllegalArgumentException - if the specified URI is not compatible with the specified transport

TLcdOWSDecodingException - if an error occurs while decoding the intial WCS response

TLcdOWSServerException - if an exception report is received from the server

TLcdOWSTransportException - if an error occurs in the transport layer while negotiation the version

TLcdOWSUnsupportedVersionException - if the specified WCS server does not support any of the WCS versions implemented by this client

createWCSClient

public static TLcdWCSClient createWCSClient(URI aURI,
 ILcdOWSTransport aTransport,
 Object aTransportData)
                                     throws TLcdOWSUnsupportedVersionException,
TLcdOWSDecodingException,
TLcdOWSServerException,
TLcdOWSTransportException

Creates a new WCS client using the specified URI. The WCS client will use the specified transport. This method will retrieve the capabilities description from the WCS server at the specified URI. Depending on the response of the WCS server this method will then perform the version negotiation process described in the WCS specification. These initial capabilities requests will use the specified transport data, if not null. Transport data can for example be used to supply authentication information, if required by the server. The WCS client returned by this method is guaranteed to be compatible with the WCS version supported by the WCS server.

Parameters:

aURI - the URI of the WCS server

aTransport - the transport to use

aTransportData - the transport data to use for the initial capabilities requests (may be null)

Returns:

a new WCS client

Throws:

NullPointerException - if either the URI or the transport is null

IllegalArgumentException - if the specified URI is not compatible with the specified transport

TLcdOWSDecodingException - if an error occurs while decoding the intial WCS response

TLcdOWSServerException - if an exception report is received from the server

TLcdOWSTransportException - if an error occurs in the transport layer while negotiation the version

TLcdOWSUnsupportedVersionException - if the specified WCS server does not support any of the WCS versions implemented by this client

getURI

public URI getURI()

Returns the URI of the WCS server. If no URI was specified at construction, the URI is determined from the capabilities: as each OGC Web Service should support a GetCapabilities request, the address associated with this request is used. If the GET request method is supported, the corresponding address is used; otherwise, it is assumed that the POST request method is supported and the corresponding address is used; if this check also fails, null is returned and the client will not be able to connect with the WCS server.

Returns:

the URI of the WCS server.

getOperation

protected final TLcdOWSOperation getOperation(String aOperationName)

Retrieves an operation based on the operation name.

Parameters:

aOperationName - the name of the operation

Returns:

the operation or null if the requested operation is not supported by the WCS server

decodeOperations

protected List decodeOperations(TLcdWCSCapabilities aCapabilities)

Returns a list of TLcdOWSOperation instances based on the contents of the provided TLcdWCSCapabilities instance. By default, this method will return a list of operations that are read from the 'Capability/Request' section of the WCS capabilities object.

Parameters:

aCapabilities - the capabilities from which to derive the list of operations

Returns:

a list of TLcdOWSOperation instances or an empty list if no operations are available

createGetCapabilitiesRequest

public TLcdWCSGetCapabilitiesRequest createGetCapabilitiesRequest()

Creates a new 'GetCapabilities' request object which is compatible with the WCS version implemented by the WCS server this client communicates with.

Returns:

a new 'GetCapabilities' request

createDescribeCoverageRequest

public TLcdWCSDescribeCoverageRequest createDescribeCoverageRequest()

Creates a new 'DescribeCoverage' request object which is compatible with the WCS version implemented by the WCS server this client communicates with.

Returns:

a new 'DescribeCoverage' request

createGetCoverageRequest

public TLcdWCSGetCoverageRequest createGetCoverageRequest()

Creates a new 'GetCoverage' request object which is compatible with the WCS version implemented by the WCS server this client communicates with.

Returns:

a new 'GetCoverage' request

getCachedCapabilities

public TLcdWCSCapabilities getCachedCapabilities()

Returns the most recent capabilities object that was requested by this client. The client will update the capabilities when it is first created and every time getCapabilities(TLcdWCSGetCapabilitiesRequest) is called.

Returns:

the capabilities of the WCS service

getCapabilities

public TLcdWCSCapabilities getCapabilities(TLcdWCSGetCapabilitiesRequest aRequest)
                                    throws TLcdOWSServerException,
TLcdOWSDecodingException,
TLcdOWSTransportException,
TLcdOWSUnsupportedVersionException

Performs the 'GetCapabilities' request.

Parameters:

aRequest - the request object containing the parameters to pass to the WCS server

Returns:

the capabilities of the WCS service

Throws:

TLcdOWSServerException - if the server returned an OpenGIS Web Service exception

TLcdOWSDecodingException - if an error occurred while decoding the 'GetCapabilities' response

TLcdOWSTransportException - if an error occurred in the transport while accessing the web service

TLcdOWSUnsupportedVersionException - if the server only supports WCS specification versions that are not supported by this client

describeCoverage

public TLcdWCSCoverageDescription describeCoverage(TLcdWCSDescribeCoverageRequest aRequest)
                                            throws TLcdOWSServerException,
TLcdOWSDecodingException,
TLcdOWSTransportException

Performs the 'DescribeCoverage' request.

Parameters:

aRequest - the request object containing the parameters to pass to the WCS server

Returns:

a description of the coverages specified in the request object

Throws:

TLcdOWSServerException - if the server returned an OpenGIS Web Service exception

TLcdOWSDecodingException - if an error occurred while decoding the 'DescribeCoverage' response

TLcdOWSTransportException - if an error occurred in the transport while accessing the web service

getCoverage

public TLcdOWSInputStream getCoverage(TLcdWCSGetCoverageRequest aRequest)
                               throws TLcdOWSServerException,
TLcdOWSDecodingException,
TLcdOWSTransportException

Performs the 'GetCoverage' request.

Parameters:

aRequest - the request object containing the parameters to pass to the WCS server

Returns:

an inputstream containing the data returned by the WCS server

Throws:

TLcdOWSServerException - if the server returned an OpenGIS Web Service exception

TLcdOWSDecodingException - if an error occurred while decoding the 'DescribeCoverage' response

TLcdOWSTransportException - if an error occurred in the transport while accessing the web service

performRequest

protected final TLcdOWSInputStream performRequest(String aOperationName,
 ILcdOWSRequest aRequest)
                                           throws TLcdOWSTransportException,
TLcdOWSServerException,
TLcdOWSDecodingException

Performs a WCS request.

Parameters:

aOperationName - the name of the operation to invoke

aRequest - the request object that should be sent

Returns:

the response input stream

Throws:

TLcdOWSServerException - if the server returned an OpenGIS Web Service exception

TLcdOWSDecodingException - if an error occurred while decoding the processing the response

TLcdOWSTransportException - if an error occurred in the transport while accessing the web service

toString

public String toString()

Overrides:

toString in class Object