Error Handling

Considerations Using Web Services

When creating MATLAB^® files that rely on a web service, consider the following:

• A server issues a time-out error. Repeat the MATLAB command.

• Internet performance might make your application performance unpredictable.

• Conventions and established procedures for services and related technologies, like WSDL and SOAP, are still evolving. You might find inconsistencies or unexpected behavior when using a web service.

• A service might change over time, which can impact its usage and results in MATLAB.

• A server issues other unrecoverable errors.

Error Handling with try/catch Statements

Use the error function in try/catch statements to catch errors that result from method calls or from the matlab.wsdl.createWSDLClient function.

Use a Local Copy of the WSDL Document

You can achieve better performance if you create a local copy and use the local copy instead of the version at the URL.

wsdlURL = ...
['http://basemap.nationalmap.gov/arcgis/services/USGSImageryOnly/MapServer?wsdl'];
wsdlFile = 'USGSImageryOnly_MapServer';
if ~exist(wsdlFile,'file') 
    websave(wsdlFile, wsdlURL)
end

Use this strategy when you do not need immediate access to data at the URL.

Java Errors Accessing Service

Once you access a service from MATLAB using the generated client code, you might get Java^® errors if:

• The WSDL for the service changes and you run matlabl.wsdl.createWSDLClient again for the same service in the same MATLAB session.

• You try to access the service using the regenerated code.

These errors are likely to occur if you modify the service between successive calls to matlabl.wsdl.createWSDLClient.

If you change a service you already accessed or generate the class files in another location, restart MATLAB.

Anonymous Types Not Supported

Anonymous XML types are unnamed types embedded in other types.