Package edu.ucsb.nceas.metacat

Class MetacatHandler

java.lang.Object

edu.ucsb.nceas.metacat.MetacatHandler

public class MetacatHandler
extends Object

General entry point for the Metacat server which is called from various mechanisms such as the standard MetacatServlet class and the various web service servlets such as RestServlet class. All application logic should be encapsulated in this class, and the calling classes should only contain parameter marshaling and unmarshalling code, delegating all else to this MetacatHandler instance.

Author:

Matthew Jones

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static enum	MetacatHandler.Action

Constructor Summary

Constructors

Constructor	Description
MetacatHandler()	Default constructor.

Method Summary

Modifier and Type	Method	Description
String	getDataDir()	Get the data object directory
String	getMetadataDir()	Get the metadata object directory
protected Path	initializeDir(String path)	Create a directory based on the given path if it is necessary.
static InputStream	read(String localId, String dataType)	Read a document from metacat and return the InputStream.
protected String	registerToDB(org.dataone.service.types.v1.Identifier pid, MetacatHandler.Action action, DBConnection conn, String user, String docType, org.dataone.service.types.v1.Identifier prePid)	Register the dataone identifier into database (the xml_documents/revisions, identifier tables).
String	save(org.dataone.service.types.v2.SystemMetadata sysmeta, boolean changeModificationDate, MetacatHandler.Action action, String docType, InputStream object, org.dataone.service.types.v2.SystemMetadata preSys, String user)	Save the object into disk
protected Path	saveBytes(InputStream object, String localId, org.dataone.service.types.v1.Checksum checksum, String docType, org.dataone.service.types.v1.Identifier pid)	Save the bytes from a input stream into disk.
protected void	sendNotSupportMessage(javax.servlet.http.HttpServletResponse response)	Send back the not-support message
protected void	validateSciMeta(byte[] object, org.dataone.service.types.v1.ObjectFormatIdentifier formatId)	Validate a scientific metadata object.
protected void	validateXmlSciMeta(byte[] object, String formatId)	Validate an XML object.

Methods inherited from class java.lang.Object

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

Constructor Details

MetacatHandler

public MetacatHandler()

Default constructor.

Method Details

initializeDir

protected Path initializeDir(String path)

Create a directory based on the given path if it is necessary. If Metacat can't read/write/exectue an exiting directory or create a new directory, null will be return. The return value is an indicator if we can use the given path as the storage path.

Parameters:

path - the path of the directory

Returns:

the path of the created directory or existing directory with proper permissions. Return null if bad things happen.

sendNotSupportMessage

protected void sendNotSupportMessage(javax.servlet.http.HttpServletResponse response)
                              throws IOException

Send back the not-support message

Parameters:

response -

Throws:

IOException

getMetadataDir

public String getMetadataDir()

Get the metadata object directory

Returns:

the metadata object directory

getDataDir

public String getDataDir()

Get the data object directory

Returns:

the data object directory

read

public static InputStream read(String localId,
 String dataType)
                        throws edu.ucsb.nceas.utilities.ParseLSIDException,
edu.ucsb.nceas.utilities.PropertyNotFoundException,
McdbException,
SQLException,
ClassNotFoundException,
IOException

Read a document from metacat and return the InputStream.

Parameters:

localId - the metacat docid to read

dataType - the type of the object associated with docid

Returns:

objectStream the document as an InputStream

Throws:

InsufficientKarmaException

edu.ucsb.nceas.utilities.ParseLSIDException

edu.ucsb.nceas.utilities.PropertyNotFoundException

McdbException

SQLException

ClassNotFoundException

IOException

save

public String save(org.dataone.service.types.v2.SystemMetadata sysmeta,
 boolean changeModificationDate,
 MetacatHandler.Action action,
 String docType,
 InputStream object,
 org.dataone.service.types.v2.SystemMetadata preSys,
 String user)
            throws org.dataone.service.exceptions.InvalidRequest,
org.dataone.service.exceptions.ServiceFailure,
org.dataone.service.exceptions.InvalidSystemMetadata,
IOException

Save the object into disk

Parameters:

sysmeta - the system metadata of the object, which contains the identifier

changeModificationDate - if Metacat needs to update the modification date of the system metadata when Metacat stores it.

action - the action of the request: Action.INSERT (new) or Action.UPDATE

docType - the type of object - data (BIN) or metadata

object - the input stream contains the content of the object

preSys - the system metadata of the obsoleted object in the update action. It will be ignored in the insert action.

user - the user initializing the request

Returns:

the local Metacat docid for this object. It also serves as its file name.

Throws:

org.dataone.service.exceptions.InvalidRequest

org.dataone.service.exceptions.ServiceFailure

org.dataone.service.exceptions.InvalidSystemMetadata

IOException

saveBytes

protected Path saveBytes(InputStream object,
 String localId,
 org.dataone.service.types.v1.Checksum checksum,
 String docType,
 org.dataone.service.types.v1.Identifier pid)
                  throws org.dataone.service.exceptions.ServiceFailure,
org.dataone.service.exceptions.InvalidSystemMetadata,
org.dataone.service.exceptions.InvalidRequest

Save the bytes from a input stream into disk.

Parameters:

object - the input stream of the object

localId - the docid which serves as the file name

checksum - checksum of the input stream from the system metadata declaration.

docType - the type of object. BIN means data; otherwise means metadata

pid - the identifier of object. It is only used for debug information.

Returns:

the file which has the input stream content

Throws:

org.dataone.service.exceptions.ServiceFailure

org.dataone.service.exceptions.InvalidSystemMetadata

org.dataone.service.exceptions.InvalidRequest

registerToDB

protected String registerToDB(org.dataone.service.types.v1.Identifier pid,
 MetacatHandler.Action action,
 DBConnection conn,
 String user,
 String docType,
 org.dataone.service.types.v1.Identifier prePid)
                       throws org.dataone.service.exceptions.ServiceFailure,
org.dataone.service.exceptions.InvalidRequest

Register the dataone identifier into database (the xml_documents/revisions, identifier tables). It also generate a local Metacat doc id.

Parameters:

pid - the dataone identifier

action - insert or update

conn - the connection to db

user - the user who requests the action

docType - BIN for data objects; the format id for metadata objects

prePid - the old identifier which will be updated. If this is an update action, you should specify it. For the insert action, it is ignored and can be null.

Returns:

the generated Metacat local docid

Throws:

org.dataone.service.exceptions.ServiceFailure

org.dataone.service.exceptions.InvalidRequest

validateSciMeta

protected void validateSciMeta(byte[] object,
 org.dataone.service.types.v1.ObjectFormatIdentifier formatId)
                        throws org.dataone.service.exceptions.InvalidRequest,
org.dataone.service.exceptions.ServiceFailure,
IOException

Validate a scientific metadata object. It will throw an InvalidRequest if it is invalid.

Parameters:

object - the content of the object. This is a byte array and so far it has not caused the memory issue. In 3.1.0 release, it will be replaced.

formatId - format id of the object

Throws:

org.dataone.service.exceptions.InvalidRequest

org.dataone.service.exceptions.ServiceFailure

ServiceException

edu.ucsb.nceas.utilities.PropertyNotFoundException

IOException

SAXException

MetacatException

validateXmlSciMeta

protected void validateXmlSciMeta(byte[] object,
 String formatId)
                           throws IOException,
org.dataone.service.exceptions.ServiceFailure,
org.dataone.service.exceptions.InvalidRequest

Validate an XML object. If it is not valid, an InvalidRequest will be thrown.

Parameters:

object - the content of the object. This is a byte array and so far it has not caused the memory issue. In 3.1.0 release, it will be replaced.

formatId - format id of the object

Throws:

IOException

org.dataone.service.exceptions.ServiceFailure

org.dataone.service.exceptions.InvalidRequest