Package org.esa.snap.core.metadata

Class XmlMetadataParser<T extends GenericXmlMetadata>

java.lang.Object

org.esa.snap.core.metadata.XmlMetadataParser<T>

public class XmlMetadataParser<T extends GenericXmlMetadata>
extends Object

SAX parser for XML metadata. This is because DOM parsing would consume more time and resources for large metadata files.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected class	XmlMetadataParser.MetadataHandler	Actual document handler implementation
protected class	XmlMetadataParser.SimpleMetadataHandler

Field Summary

Fields

Modifier and Type	Field	Description
protected Class	fileClass
protected String	schemaBasePath
protected String[]	schemaLocations

Constructor Summary

Constructors

Constructor	Description
XmlMetadataParser(Class metadataClass)	Constructs an instance of XmlMetadataParser for the given metadata class.

Method Summary

Modifier and Type	Method	Description
protected ProductData	inferType(String elementName, String value)	Tries to infer the type of the element, based on the available XSD schema definition.
T	parse(InputStream inputStream)	Tries to parse the given InputStream (which may be a string or a stream over a file).
MetadataElement	parse(Path file, Set<String> excludes)
protected void	setSchemaBasePath(String schemaBasePath)	Sets the location of the schema base path that should be used for XSD schema validation.
protected void	setSchemaLocations(String[] schemaLocations)	Sets the location(s) of the XSD schema(s) that should be used for XSD schema validation.
protected boolean	shouldValidateSchema()	Indicates if the XSD validation should be performed.

Methods inherited from class java.lang.Object

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

Field Detail

fileClass

protected Class fileClass

schemaLocations

protected String[] schemaLocations

schemaBasePath

protected String schemaBasePath

Constructor Detail

XmlMetadataParser

public XmlMetadataParser(Class metadataClass)

Constructs an instance of XmlMetadataParser for the given metadata class.

Parameters:

metadataClass - The class of metadata (it should be derived from XmlMetadata).

Method Detail

inferType

protected ProductData inferType(String elementName,
                                String value)

Tries to infer the type of the element, based on the available XSD schema definition. If no schema definition exist, the type will always be ProductData.ASCII.

Parameters:

elementName - The name of the XML element.

value - The value of the XML element.

Returns:

An instance of ProductData wrapping the element value.

parse

public T parse(InputStream inputStream)
        throws ParserConfigurationException,
               SAXException,
               IOException

Tries to parse the given InputStream (which may be a string or a stream over a file).

Parameters:

inputStream - The input stream

Returns:

If successful, it returns an instance of a class extending XmlMetadata.

Throws:

ParserConfigurationException - Exception is thrown by the underlying SAX mechanism.

SAXException - Exception is thrown if the XML is not well formed.

IOException - Exception is thrown if there is a problem reading the input stream.

parse

public MetadataElement parse(Path file,
                             Set<String> excludes)
                      throws ParserConfigurationException,
                             SAXException,
                             IOException

Throws:

ParserConfigurationException

SAXException

IOException

shouldValidateSchema

protected boolean shouldValidateSchema()

Indicates if the XSD validation should be performed. Override this in derived classes to enable schema validation.

Returns:

The default implementation always returns false. In a derived class, true would mean that the XML schema validation should be performed.

setSchemaBasePath

protected void setSchemaBasePath(String schemaBasePath)

Sets the location of the schema base path that should be used for XSD schema validation.

Parameters:

schemaBasePath - The schema base path.

setSchemaLocations

protected void setSchemaLocations(String[] schemaLocations)

Sets the location(s) of the XSD schema(s) that should be used for XSD schema validation.

Parameters:

schemaLocations - An array of schema locations.