org.apache.metamodel.json

Class JsonDataContext

java.lang.Object

org.apache.metamodel.AbstractDataContext

org.apache.metamodel.QueryPostprocessDataContext

org.apache.metamodel.json.JsonDataContext

All Implemented Interfaces:

HasReadTypeConverters, DataContext, DocumentSourceProvider

public class JsonDataContext
extends QueryPostprocessDataContext
implements DocumentSourceProvider

DataContext implementation that works on JSON files or Resources.

Field Summary

Fields inherited from class org.apache.metamodel.QueryPostprocessDataContext

INFORMATION_SCHEMA_NAME, SYSTEM_PROPERTY_CREATE_DEFAULT_TABLE_ALIAS

Constructor Summary

Constructors

Constructor and Description
JsonDataContext(File file)
JsonDataContext(Resource resource)
JsonDataContext(Resource resource, SchemaBuilder schemaBuilder)

Method Summary

Modifier and Type	Method and Description
DocumentSource	getDocumentSourceForTable(String sourceCollectionName) Gets a DocumentSource for a particular source collection.
protected Schema	getMainSchema()
protected String	getMainSchemaName()
DocumentSource	getMixedDocumentSourceForSampling() Gets a DocumentSource containing documents of mixed origin and type.
protected DataSet	materializeMainSchemaTable(Table table, List<Column> columns, int maxRows) Executes a simple one-table query against a table in the main schema of the subclasses of this class.

Methods inherited from class org.apache.metamodel.QueryPostprocessDataContext

addConverter, executeCountQuery, executePrimaryKeyLookupQuery, executeQuery, getDefaultSchemaName, getSchemaByNameInternal, getSchemaNamesInternal, isMainSchemaTable, isScalarFunctionMaterialized, materializeFromItem, materializeMainSchemaTable, materializeMainSchemaTable, materializeMainSchemaTableSelect, materializeTable

Methods inherited from class org.apache.metamodel.AbstractDataContext

compileQuery, executeQuery, executeQuery, getColumnByQualifiedLabel, getDefaultSchema, getSchemaByName, getSchemaNames, getSchemas, getTableByQualifiedLabel, isQualifiedPathDelim, onSchemaCacheRefreshed, parseQuery, query, refreshSchemas

Methods inherited from class java.lang.Object

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

Constructor Detail

JsonDataContext

public JsonDataContext(File file)

JsonDataContext

public JsonDataContext(Resource resource)

JsonDataContext

public JsonDataContext(Resource resource,
                       SchemaBuilder schemaBuilder)

Method Detail

getMainSchema

protected Schema getMainSchema()
                        throws MetaModelException

Specified by:

getMainSchema in class QueryPostprocessDataContext

Returns:

the main schema that subclasses of this class produce

Throws:

MetaModelException

getMainSchemaName

protected String getMainSchemaName()
                            throws MetaModelException

Specified by:

getMainSchemaName in class QueryPostprocessDataContext

Returns:

the name of the main schema that subclasses of this class produce

Throws:

MetaModelException

materializeMainSchemaTable

protected DataSet materializeMainSchemaTable(Table table,
                                             List<Column> columns,
                                             int maxRows)

Description copied from class: QueryPostprocessDataContext

Executes a simple one-table query against a table in the main schema of the subclasses of this class.

Specified by:

materializeMainSchemaTable in class QueryPostprocessDataContext

Parameters:

table - the table to query

columns - the columns of the table to query

maxRows - the maximum amount of rows needed or -1 if all rows are wanted.

Returns:

a dataset with the raw table/column content.

getMixedDocumentSourceForSampling

public DocumentSource getMixedDocumentSourceForSampling()

Description copied from interface: DocumentSourceProvider

Gets a DocumentSource containing documents of mixed origin and type.

Specified by:

getMixedDocumentSourceForSampling in interface DocumentSourceProvider

Returns:

getDocumentSourceForTable

public DocumentSource getDocumentSourceForTable(String sourceCollectionName)

Description copied from interface: DocumentSourceProvider

Gets a DocumentSource for a particular source collection. See Document.getSourceCollectionName().

Specified by:

getDocumentSourceForTable in interface DocumentSourceProvider

Returns: