Package org.apache.drill.exec.record.metadata.schema

Class PathSchemaProvider

java.lang.Object

org.apache.drill.exec.record.metadata.schema.PathSchemaProvider

All Implemented Interfaces:

SchemaProvider

Direct Known Subclasses:

FsMetastoreSchemaProvider

public class PathSchemaProvider
extends Object
implements SchemaProvider

Is used to provide schema using given schema file name and path.

Field Summary

Fields

Modifier and Type	Field	Description
static final com.fasterxml.jackson.databind.ObjectReader	READER	Reader used to read JSON schema from file into into SchemaContainer.
static final com.fasterxml.jackson.databind.ObjectWriter	WRITER	Writer used to write content from SchemaContainer into JSON file.

Fields inherited from interface org.apache.drill.exec.record.metadata.schema.SchemaProvider

DEFAULT_SCHEMA_NAME

Constructor Summary

Constructors

Constructor	Description
PathSchemaProvider(org.apache.hadoop.fs.FileSystem fs, org.apache.hadoop.fs.Path path)
PathSchemaProvider(org.apache.hadoop.fs.Path path)

Method Summary

Modifier and Type	Method	Description
protected SchemaContainer	createTableSchema(String schema, Map<String,String> properties)
void	delete()	Deletes schema.
boolean	exists()	Checks if schema exists.
SchemaContainer	read()	Reads schema into SchemaContainer.
void	store(String schema, Map<String,String> properties, StorageProperties storageProperties)	Stores given schema definition and properties.

Methods inherited from class java.lang.Object

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

Field Details

READER

public static final com.fasterxml.jackson.databind.ObjectReader READER

Reader used to read JSON schema from file into into SchemaContainer. Allows comment inside the JSON file.

WRITER

public static final com.fasterxml.jackson.databind.ObjectWriter WRITER

Writer used to write content from SchemaContainer into JSON file.

Constructor Details

PathSchemaProvider

public PathSchemaProvider(org.apache.hadoop.fs.Path path)
                   throws IOException

Throws:

IOException

PathSchemaProvider

public PathSchemaProvider(org.apache.hadoop.fs.FileSystem fs,
 org.apache.hadoop.fs.Path path)
                   throws IOException

Throws:

IOException

Method Details

delete

public void delete()
            throws IOException

Description copied from interface: SchemaProvider

Deletes schema.

Specified by:

delete in interface SchemaProvider

Throws:

IOException

store

public void store(String schema,
 Map<String,String> properties,
 StorageProperties storageProperties)
           throws IOException

Description copied from interface: SchemaProvider

Stores given schema definition and properties.

Specified by:

store in interface SchemaProvider

Parameters:

schema - schema definition

properties - map of properties

storageProperties - storage properties

Throws:

IOException

read

public SchemaContainer read()
                     throws IOException

Description copied from interface: SchemaProvider

Reads schema into SchemaContainer. Depending on implementation, can read from a file or from the given input.

Specified by:

read in interface SchemaProvider

Returns:

table schema instance

Throws:

IOException

exists

public boolean exists()
               throws IOException

Description copied from interface: SchemaProvider

Checks if schema exists.

Specified by:

exists in interface SchemaProvider

Returns:

true if schema exists, false otherwise

Throws:

IOException

createTableSchema

protected SchemaContainer createTableSchema(String schema,
 Map<String,String> properties)
                                     throws IOException

Throws:

IOException